|
Bruce Crain
This reminds me of something Scott Swing and I conversed about. Scott said someone flew the LS1 without a sparrow strainer because the absence of it created less drag for a race he had entered. Huge stick pressure but at higher airspeed the pressure (I think) was less because of more lift on the canard. (could have misunderstood Scott on this).
So the higher the Mach number the less forward pressure on the stick.  Bruce
---------- Original Message ---------- From: "Jay Scheevel" <jay@...> To: <main@Q-List.groups.io> Subject: [Q-List] Bruce's tuft study on sparrow strainers Date: Mon, 16 Dec 2019 09:09:58 -0700
Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do.
Seriously, That is an interesting observation. Ideally, you would like your “trim” surfaces, such as the sparrow strainer to be well behaved under all flight conditions, but you have demonstrated that this is not the case. The sparrow strainer flies at a high AOA (negative) all the time, so as to apply a large load to the trailing edge of the elevator, push it into an accelerated condition and boom, you get it to stall. The need for them is entirely the because the aft-1/3 of the LS-1 airfoil has a significant camber on the underside. This camber is by design yielding favorable characteristics when incorporated on a non-articulated airfoil, but when you incorporate an articulated trailing edge (elevator), then the asymmetric force becomes torque on the torque tube and stick deflection instead of into a forward pitching component applied to the rigid wing structure. By countering this effect with the sparrow strainer you actually loose some of the positive characteristics of the pitching moment, and you add a lot of drag. If you could manage it as a pilot, and this is not recommended, the LS-1 would fly better and be more efficient if you could hold the elevator neutral with the stick. But this would require always be pulling lots of aft stick-force. The stick force would be very large in full cruise, and you would never find a hands off condition. It gives you an appreciation for the force that the sparrow strainer supports are experiencing constantly in flight, and why one might potentially depart the aircraft….requiring above average flying skills to recover.
I have modeled the forces on the LS-1 elevator and have also designed a modified LS-1 airfoil with the rear portion of the camber removed, where the forces on the redesigned elevator are balanced, (so the sparrow strainer would not be required). I have thought that sometime I would like to build a new set of these redesigned elevators and put them on my plane, but I am just getting comfortable flying with the plans design. On the redesigned airfoil, the lift profile and polars are essentially identical to the LS-1, but what is the big unknown is how the redesigned elevator would impact that stall behavior. Small changes at the trailing edge can be quite impactful on stall, and my modeling method cannot model the complexity of airflow at stall.
Cheers,
Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Bruce Crain
Sent: Sunday, December 15, 2019 9:32 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Not sure I really care to know. Either way I will still be aviating in both and won't put any more sound insulation in either one. (more weight)
On a side note I have been doing some tuft testing which might be more informational. I have found out that if I pull up the nose and then unload it by pushing forward on the stick my sparrow strainers are stalling on the bottom side. My TriQ will not recover in most instances until I stall out or slow down the airspeed a bunch so that I can pull the stick enough for the strainers to reattach the air underneath them. I just received some vortex generators to put on the bottom of the strainers to do more testing and will hopefully have them in place this week to test.
I have noticed in the past that when I do an aileron roll this happens. I have been all though the elevators and ailerons to make sure they were tight and they now are very solid. So then I thought that maybe the wingtip vortices were coming up from the canard and rolling down on the main wing. That never really looked like a good theory. So I installed yarn tufts to see just what was going on. When I flew it started to dawn on me that the elevator was coming up every time I experienced the phenomenon. So I had a good idea that something much simpler was happening and it kept pointing to the sparrow strainer. After talking with Paul Fisher, Jerry Marstall, Sammy Hoskins, and even Scott Swing at Velocity I decided we were looking at a stall. Sure enough when I went up with the tufts in place on the canard and the top and bottom of the sparrow strainers I thought "what if I just pull up and then push forward on the stick could I replicate the problem". When I pulled up and then unloaded the canard by pushing over the sparrow strainers held for a bit and then they relaxed to stick forward an inch or so. I looked out and saw the elevators up about and inch or so and videoed the tufts on the bottom of the strainer disappear and the tufts on the top tufts wrap around the back of the strainer and disappear forward under the strainer! I spoke with Paul, Jerry and Scott again and Scott was freaked but agreed that was what is happening.
Bingo! Now I have to fix it so that is where the vortex generator come in. The strainers are a really sensitive trim from dealing with them in the past plus I have them mounted half way outboard on the elevator. I also have 1.2 degrees incidence up on the canard and .8 degrees up on the main wing so we are talking apples to oranges.
Sure I could just fly the Q and not go negative on the elevator enough to stall them but I like to do aileron rolls when I am board. I believe you and I experienced the stall when you were getting time in my Q before your first flight. So we educate and experiment and come out improving the species.
---------- Original Message ----------
From: "Jay Scheevel" <jay@...>
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 19:53:06 -0700
If you have an iPhone it has an app available that measures abient noise level. You could give that a try.
Sent from my Verizon Wireless 4G LTE DROID
Bruce Crain <jcrain2@...> wrote:
I have not noticed which one is quieter. Will try to do that in the future. Trouble is remembering how loud the other plane is between switches.
I will tell Charlie hello for you Dr Mike!
Bruce
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001@...>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Mon, 16 Dec 2019 01:37:25 +0000 (UTC)
Hi Mike,
My RV6A is noisy. I have a Clark headset modified for active noise reduction but my new Zulu 3 is quieter. I have a Lycoming O-320 E2D 150 with a metal Sensinich prop. I have problem believing a Quickie 200 is quieter.
Mike
On Sun, Dec 15, 2019 at 7:33 PM, Mike Dwyer
I flew in a RV4 recently and I think the inside cockpit of the RV is a lot noisier than a Q200. I'd expect the fiberglass sandwich to dampen some noise.
On Sun, Dec 15, 2019 at 8:14 PM Bruce Crain <jcrain2@...> wrote:
Sweet! Hope you design a mach .5 airfoil for the Quickie guys Wouldn't that be sweet!
I still have my TriQ 200 but I went over to the "Dark Side" when my hanger mate Charlie Calivas sold me his RV 6 for a song and a dance and then proceeded to help me rebuild the engine! My son Jake calls me "2 planes Crain"!
Have a Merry Christmas!
Bruce and Honeylamb Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 04:06:52 +0000 (UTC)
Bruce!
Good to hear from you as well. Things are great in Wichita. I'm still designing GA airfoils and flying my RV6A and Cessna 120. I went through Emporia two weeks ago and it reminded me of when you, your son, and I got weathered in coming back from the Quickie fly-in at Ottawa.
Great hearing from you! My thanks to the Q-List group for letting me "announce" our moving Shuck Airfoil from Yahoo! Groups to Groups.io !
On Sat, Dec 14, 2019 at 9:44 PM, Bruce Crain
Good to hear from you again Dr Shuck! How are things in Wichita?
Bruce Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 00:24:29 +0000 (UTC)
Just to let you know I am in process of moving the former Yahoo! Groups Shuck Airfoil to:
I was late getting the mailing list moved over so I would be very thankful if you would post this as many
of the Shuck Airfoil group at Yahoo! Groups also were members of Q-List.
Moderator of the former Yahoo! Groups Shuck Airfoil
|
|
|
Jay, The hinge pin on the Roncz canard elevator is not concentric with the elevator torque tube. It is approximately 0.1” from the inner surface of the torque tube at the extreme bottom of the tube, much closer to the lower surface of the elevator than depicted in your initial image. Those hot wire templates look legit, though I wouldn’t trust their dimensional accuracy enough to build anything from them…. David J. Gall
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Jay Scheevel Sent: Monday, December 16, 2019 4:19 PM To: main@Q-List.groups.io Subject: Re: [Q-List] Bruce's tuft study on sparrow strainers From that most reliable of sources, “the internet” 😊 http://www.angelfire.com/on/dragonflyaircraft/airfoils.html Look about midway down the page. I think the elevator hinge location is accurate, at least according to these hotwire templates from the Canard Zone Forums 
Cheers, Jay Jay, P.S. - Where’d you find a picture of a Roncz R1145MS with a powered trim tab? THAT was never part of the Roncz canard plans.
- That depiction of the Roncz canard is actually incorrect. The elevator hinge line is in the wrong place. It also looks like it has a Jimmy Durante schnoz (bump on the nose)….
David J. Gall Jay, No, but you’re getting MUCH closer. Think full-span fixed trim tab. Like on the paper airplane you made as a kid: bend the trailing edge up a little bit. The million-dollar answer that makes guys like Roncz famous is to define “how much” to bend it up. So, go back to the Rutan Canard Pusher newsletters where Burt defines the criteria, then go get X-Foil or even Roncz’s own tool (the modified Eppler code) and solve the problem the same way Roncz did. It only took Roncz et. al four canards to get the whole thing right – you should be able to do this lesser task with just one (full-span) elevator, maybe one (full-span) elevator modified (slightly) a couple times to tweak it to perfection…. David J. Gall OK, re-read your note, and now I get it: Use Roncz anti-servo trim tab on the stock LS-1 elevator. Right? If so, you are saying mount a servo such as shown on the trailing edge below? 
Cheers, Jay Nope. That’s not what I said. David “Jimmeh” Gall On Dec 16, 2019, at 12:29 PM, Jay Scheevel <jay@...> wrote:
Thanks David, Am aware of the Roncz canard and its implementation on the EZ, but to directly convert the Quickie to that implementation would require re-engineering the elevator actuator. Could do that if starting my canard build over from scratch, but to retrofit on the existing Q2 with the LS-1 already installed would be difficult. The Roncz elevator solution is a sort of a fowler flap and would also require installation of the trailing edge trim. My design is a compromise to be sure, but could be directly retrofit in the existing slot with the same torque tube system as is currently in place and eliminate the sparrow strainer. Don’t know if that will ever happen, but it would be a doable retrofit. Cheers,
Jay Jay, John Roncz came up with the solution to this many years ago. It’s called the “Roncz canard” in the Long-EZ community. It’s an excellent airfoil, but particularly important is what he did to the elevator. The same technique could be used on the LS-1 elevator to mitigate the elevator hinge moment. It can be modeled fairly accurately in X-foil or in Roncz’s modified Eppler airfoil code that he used back then (freely available on the internet). Just gotta tweak it so the elevator floating angle is stable and appropriate for the airplane’s approximate maximum range low cruise airspeed so that if the trim and elevator control systems accidentally disconnect in flight the airplane will be able to continue flight and land using engine power modulation (and reflex if installed) as primary pitch control. Rutan laid out all these requirements in one of the Canard Pusher newsletters in the 1980s. David J. Gall Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do. Seriously, That is an interesting observation. Ideally, you would like your “trim” surfaces, such as the sparrow strainer to be well behaved under all flight conditions, but you have demonstrated that this is not the case. The sparrow strainer flies at a high AOA (negative) all the time, so as to apply a large load to the trailing edge of the elevator, push it into an accelerated condition and boom, you get it to stall. The need for them is entirely the because the aft-1/3 of the LS-1 airfoil has a significant camber on the underside. This camber is by design yielding favorable characteristics when incorporated on a non-articulated airfoil, but when you incorporate an articulated trailing edge (elevator), then the asymmetric force becomes torque on the torque tube and stick deflection instead of into a forward pitching component applied to the rigid wing structure. By countering this effect with the sparrow strainer you actually loose some of the positive characteristics of the pitching moment, and you add a lot of drag. If you could manage it as a pilot, and this is not recommended, the LS-1 would fly better and be more efficient if you could hold the elevator neutral with the stick. But this would require always be pulling lots of aft stick-force. The stick force would be very large in full cruise, and you would never find a hands off condition. It gives you an appreciation for the force that the sparrow strainer supports are experiencing constantly in flight, and why one might potentially depart the aircraft….requiring above average flying skills to recover. I have modeled the forces on the LS-1 elevator and have also designed a modified LS-1 airfoil with the rear portion of the camber removed, where the forces on the redesigned elevator are balanced, (so the sparrow strainer would not be required). I have thought that sometime I would like to build a new set of these redesigned elevators and put them on my plane, but I am just getting comfortable flying with the plans design. On the redesigned airfoil, the lift profile and polars are essentially identical to the LS-1, but what is the big unknown is how the redesigned elevator would impact that stall behavior. Small changes at the trailing edge can be quite impactful on stall, and my modeling method cannot model the complexity of airflow at stall. Cheers, Jay From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Bruce Crain
Sent: Sunday, December 15, 2019 9:32 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil Not sure I really care to know. Either way I will still be aviating in both and won't put any more sound insulation in either one. (more weight) On a side note I have been doing some tuft testing which might be more informational. I have found out that if I pull up the nose and then unload it by pushing forward on the stick my sparrow strainers are stalling on the bottom side. My TriQ will not recover in most instances until I stall out or slow down the airspeed a bunch so that I can pull the stick enough for the strainers to reattach the air underneath them. I just received some vortex generators to put on the bottom of the strainers to do more testing and will hopefully have them in place this week to test. I have noticed in the past that when I do an aileron roll this happens. I have been all though the elevators and ailerons to make sure they were tight and they now are very solid. So then I thought that maybe the wingtip vortices were coming up from the canard and rolling down on the main wing. That never really looked like a good theory. So I installed yarn tufts to see just what was going on. When I flew it started to dawn on me that the elevator was coming up every time I experienced the phenomenon. So I had a good idea that something much simpler was happening and it kept pointing to the sparrow strainer. After talking with Paul Fisher, Jerry Marstall, Sammy Hoskins, and even Scott Swing at Velocity I decided we were looking at a stall. Sure enough when I went up with the tufts in place on the canard and the top and bottom of the sparrow strainers I thought "what if I just pull up and then push forward on the stick could I replicate the problem". When I pulled up and then unloaded the canard by pushing over the sparrow strainers held for a bit and then they relaxed to stick forward an inch or so. I looked out and saw the elevators up about and inch or so and videoed the tufts on the bottom of the strainer disappear and the tufts on the top tufts wrap around the back of the strainer and disappear forward under the strainer! I spoke with Paul, Jerry and Scott again and Scott was freaked but agreed that was what is happening. Bingo! Now I have to fix it so that is where the vortex generator come in. The strainers are a really sensitive trim from dealing with them in the past plus I have them mounted half way outboard on the elevator. I also have 1.2 degrees incidence up on the canard and .8 degrees up on the main wing so we are talking apples to oranges. Sure I could just fly the Q and not go negative on the elevator enough to stall them but I like to do aileron rolls when I am board. I believe you and I experienced the stall when you were getting time in my Q before your first flight. So we educate and experiment and come out improving the species.
---------- Original Message ----------
From: "Jay Scheevel" <jay@...>
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 19:53:06 -0700 If you have an iPhone it has an app available that measures abient noise level. You could give that a try. Sent from my Verizon Wireless 4G LTE DROID
Bruce Crain <jcrain2@...> wrote:
I have not noticed which one is quieter. Will try to do that in the future. Trouble is remembering how loud the other plane is between switches. I will tell Charlie hello for you Dr Mike! Bruce
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001@...>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Mon, 16 Dec 2019 01:37:25 +0000 (UTC)
Hi Mike, My RV6A is noisy. I have a Clark headset modified for active noise reduction but my new Zulu 3 is quieter. I have a Lycoming O-320 E2D 150 with a metal Sensinich prop. I have problem believing a Quickie 200 is quieter. Mike On Sun, Dec 15, 2019 at 7:33 PM, Mike Dwyer I flew in a RV4 recently and I think the inside cockpit of the RV is a lot noisier than a Q200. I'd expect the fiberglass sandwich to dampen some noise. On Sun, Dec 15, 2019 at 8:14 PM Bruce Crain <jcrain2@...> wrote: Sweet! Hope you design a mach .5 airfoil for the Quickie guys Wouldn't that be sweet! I still have my TriQ 200 but I went over to the "Dark Side" when my hanger mate Charlie Calivas sold me his RV 6 for a song and a dance and then proceeded to help me rebuild the engine! My son Jake calls me "2 planes Crain"!
Have a Merry Christmas! Bruce and Honeylamb Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 04:06:52 +0000 (UTC)
Bruce! Good to hear from you as well. Things are great in Wichita. I'm still designing GA airfoils and flying my RV6A and Cessna 120. I went through Emporia two weeks ago and it reminded me of when you, your son, and I got weathered in coming back from the Quickie fly-in at Ottawa. Great hearing from you! My thanks to the Q-List group for letting me "announce" our moving Shuck Airfoil from Yahoo! Groups to Groups.io ! On Sat, Dec 14, 2019 at 9:44 PM, Bruce Crain Good to hear from you again Dr Shuck! How are things in Wichita? Bruce Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 00:24:29 +0000 (UTC) Just to let you know I am in process of moving the former Yahoo! Groups Shuck Airfoil to: I was late getting the mailing list moved over so I would be very thankful if you would post this as many of the Shuck Airfoil group at Yahoo! Groups also were members of Q-List. Moderator of the former Yahoo! Groups Shuck Airfoil
|
|
|
Jay, BINGO! Again, you don’t want the float angle for cruise, you want the float angle for LOW cruise/max range or even a little slower. Remember, the worst-case scenario is that you are going to crash at that speed (out of options out of gas). The best case scenario is that you’re going to limp the rest of the way across the North Sea at ultra-slow cruise (but still have enough gas because you’re at max range speed) and then land at that speed (because you don’t have elevator to slow down or flare). Yeah, yeah, it’s all a game of hypotheticals, but George Mead (one of Burt’s early employees and a very talented design engineer in his own right) apparently didn’t set up his elevators this way on the “Pugmobile” canard and it ended up killing him and three NASA engineers…. David J. Gall
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Jay Scheevel Sent: Monday, December 16, 2019 4:07 PM To: main@Q-List.groups.io Subject: Re: [Q-List] Bruce's tuft study on sparrow strainers Thanks for the clarification, David. Starting to sound kind of like what I did in my model. I modified the elevator portion of the LS-1 to neutralize the moment on the elevator at zero AOA (plans) . What I did not do is figure out what additional trailing edge modification was necessary to establish the float angle for cruise. I think we are coming into alignment now. By the way, Martin Skiby did what you are describing, but on the fixed trailing edge portion of his main wing in order get the cruise AOA optimized for the two lifting surfaces (on his tri-Q) Cheers, Jay Jay, No, but you’re getting MUCH closer. Think full-span fixed trim tab. Like on the paper airplane you made as a kid: bend the trailing edge up a little bit. The million-dollar answer that makes guys like Roncz famous is to define “how much” to bend it up. So, go back to the Rutan Canard Pusher newsletters where Burt defines the criteria, then go get X-Foil or even Roncz’s own tool (the modified Eppler code) and solve the problem the same way Roncz did. It only took Roncz et. al four canards to get the whole thing right – you should be able to do this lesser task with just one (full-span) elevator, maybe one (full-span) elevator modified (slightly) a couple times to tweak it to perfection…. David J. Gall OK, re-read your note, and now I get it: Use Roncz anti-servo trim tab on the stock LS-1 elevator. Right? If so, you are saying mount a servo such as shown on the trailing edge below? 
Cheers, Jay Nope. That’s not what I said. David “Jimmeh” Gall On Dec 16, 2019, at 12:29 PM, Jay Scheevel <jay@...> wrote:
Thanks David, Am aware of the Roncz canard and its implementation on the EZ, but to directly convert the Quickie to that implementation would require re-engineering the elevator actuator. Could do that if starting my canard build over from scratch, but to retrofit on the existing Q2 with the LS-1 already installed would be difficult. The Roncz elevator solution is a sort of a fowler flap and would also require installation of the trailing edge trim. My design is a compromise to be sure, but could be directly retrofit in the existing slot with the same torque tube system as is currently in place and eliminate the sparrow strainer. Don’t know if that will ever happen, but it would be a doable retrofit. Cheers,
Jay Jay, John Roncz came up with the solution to this many years ago. It’s called the “Roncz canard” in the Long-EZ community. It’s an excellent airfoil, but particularly important is what he did to the elevator. The same technique could be used on the LS-1 elevator to mitigate the elevator hinge moment. It can be modeled fairly accurately in X-foil or in Roncz’s modified Eppler airfoil code that he used back then (freely available on the internet). Just gotta tweak it so the elevator floating angle is stable and appropriate for the airplane’s approximate maximum range low cruise airspeed so that if the trim and elevator control systems accidentally disconnect in flight the airplane will be able to continue flight and land using engine power modulation (and reflex if installed) as primary pitch control. Rutan laid out all these requirements in one of the Canard Pusher newsletters in the 1980s. David J. Gall Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do. Seriously, That is an interesting observation. Ideally, you would like your “trim” surfaces, such as the sparrow strainer to be well behaved under all flight conditions, but you have demonstrated that this is not the case. The sparrow strainer flies at a high AOA (negative) all the time, so as to apply a large load to the trailing edge of the elevator, push it into an accelerated condition and boom, you get it to stall. The need for them is entirely the because the aft-1/3 of the LS-1 airfoil has a significant camber on the underside. This camber is by design yielding favorable characteristics when incorporated on a non-articulated airfoil, but when you incorporate an articulated trailing edge (elevator), then the asymmetric force becomes torque on the torque tube and stick deflection instead of into a forward pitching component applied to the rigid wing structure. By countering this effect with the sparrow strainer you actually loose some of the positive characteristics of the pitching moment, and you add a lot of drag. If you could manage it as a pilot, and this is not recommended, the LS-1 would fly better and be more efficient if you could hold the elevator neutral with the stick. But this would require always be pulling lots of aft stick-force. The stick force would be very large in full cruise, and you would never find a hands off condition. It gives you an appreciation for the force that the sparrow strainer supports are experiencing constantly in flight, and why one might potentially depart the aircraft….requiring above average flying skills to recover. I have modeled the forces on the LS-1 elevator and have also designed a modified LS-1 airfoil with the rear portion of the camber removed, where the forces on the redesigned elevator are balanced, (so the sparrow strainer would not be required). I have thought that sometime I would like to build a new set of these redesigned elevators and put them on my plane, but I am just getting comfortable flying with the plans design. On the redesigned airfoil, the lift profile and polars are essentially identical to the LS-1, but what is the big unknown is how the redesigned elevator would impact that stall behavior. Small changes at the trailing edge can be quite impactful on stall, and my modeling method cannot model the complexity of airflow at stall. Cheers, Jay From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Bruce Crain
Sent: Sunday, December 15, 2019 9:32 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil Not sure I really care to know. Either way I will still be aviating in both and won't put any more sound insulation in either one. (more weight) On a side note I have been doing some tuft testing which might be more informational. I have found out that if I pull up the nose and then unload it by pushing forward on the stick my sparrow strainers are stalling on the bottom side. My TriQ will not recover in most instances until I stall out or slow down the airspeed a bunch so that I can pull the stick enough for the strainers to reattach the air underneath them. I just received some vortex generators to put on the bottom of the strainers to do more testing and will hopefully have them in place this week to test. I have noticed in the past that when I do an aileron roll this happens. I have been all though the elevators and ailerons to make sure they were tight and they now are very solid. So then I thought that maybe the wingtip vortices were coming up from the canard and rolling down on the main wing. That never really looked like a good theory. So I installed yarn tufts to see just what was going on. When I flew it started to dawn on me that the elevator was coming up every time I experienced the phenomenon. So I had a good idea that something much simpler was happening and it kept pointing to the sparrow strainer. After talking with Paul Fisher, Jerry Marstall, Sammy Hoskins, and even Scott Swing at Velocity I decided we were looking at a stall. Sure enough when I went up with the tufts in place on the canard and the top and bottom of the sparrow strainers I thought "what if I just pull up and then push forward on the stick could I replicate the problem". When I pulled up and then unloaded the canard by pushing over the sparrow strainers held for a bit and then they relaxed to stick forward an inch or so. I looked out and saw the elevators up about and inch or so and videoed the tufts on the bottom of the strainer disappear and the tufts on the top tufts wrap around the back of the strainer and disappear forward under the strainer! I spoke with Paul, Jerry and Scott again and Scott was freaked but agreed that was what is happening. Bingo! Now I have to fix it so that is where the vortex generator come in. The strainers are a really sensitive trim from dealing with them in the past plus I have them mounted half way outboard on the elevator. I also have 1.2 degrees incidence up on the canard and .8 degrees up on the main wing so we are talking apples to oranges. Sure I could just fly the Q and not go negative on the elevator enough to stall them but I like to do aileron rolls when I am board. I believe you and I experienced the stall when you were getting time in my Q before your first flight. So we educate and experiment and come out improving the species.
---------- Original Message ----------
From: "Jay Scheevel" <jay@...>
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 19:53:06 -0700 If you have an iPhone it has an app available that measures abient noise level. You could give that a try. Sent from my Verizon Wireless 4G LTE DROID
Bruce Crain <jcrain2@...> wrote:
I have not noticed which one is quieter. Will try to do that in the future. Trouble is remembering how loud the other plane is between switches. I will tell Charlie hello for you Dr Mike! Bruce
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001@...>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Mon, 16 Dec 2019 01:37:25 +0000 (UTC)
Hi Mike, My RV6A is noisy. I have a Clark headset modified for active noise reduction but my new Zulu 3 is quieter. I have a Lycoming O-320 E2D 150 with a metal Sensinich prop. I have problem believing a Quickie 200 is quieter. Mike On Sun, Dec 15, 2019 at 7:33 PM, Mike Dwyer I flew in a RV4 recently and I think the inside cockpit of the RV is a lot noisier than a Q200. I'd expect the fiberglass sandwich to dampen some noise. On Sun, Dec 15, 2019 at 8:14 PM Bruce Crain <jcrain2@...> wrote: Sweet! Hope you design a mach .5 airfoil for the Quickie guys Wouldn't that be sweet! I still have my TriQ 200 but I went over to the "Dark Side" when my hanger mate Charlie Calivas sold me his RV 6 for a song and a dance and then proceeded to help me rebuild the engine! My son Jake calls me "2 planes Crain"!
Have a Merry Christmas! Bruce and Honeylamb Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 04:06:52 +0000 (UTC)
Bruce! Good to hear from you as well. Things are great in Wichita. I'm still designing GA airfoils and flying my RV6A and Cessna 120. I went through Emporia two weeks ago and it reminded me of when you, your son, and I got weathered in coming back from the Quickie fly-in at Ottawa. Great hearing from you! My thanks to the Q-List group for letting me "announce" our moving Shuck Airfoil from Yahoo! Groups to Groups.io ! On Sat, Dec 14, 2019 at 9:44 PM, Bruce Crain Good to hear from you again Dr Shuck! How are things in Wichita? Bruce Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 00:24:29 +0000 (UTC) Just to let you know I am in process of moving the former Yahoo! Groups Shuck Airfoil to: I was late getting the mailing list moved over so I would be very thankful if you would post this as many of the Shuck Airfoil group at Yahoo! Groups also were members of Q-List. Moderator of the former Yahoo! Groups Shuck Airfoil
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|
|
Jay Scheevel
toggle quoted message
Show quoted text
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of David J. Gall Sent: Monday, December 16, 2019 5:04 PM To: main@Q-List.groups.io Subject: Re: [Q-List] Bruce's tuft study on sparrow strainers Jay, P.S. - Where’d you find a picture of a Roncz R1145MS with a powered trim tab? THAT was never part of the Roncz canard plans.
- That depiction of the Roncz canard is actually incorrect. The elevator hinge line is in the wrong place. It also looks like it has a Jimmy Durante schnoz (bump on the nose)….
David J. Gall Jay, No, but you’re getting MUCH closer. Think full-span fixed trim tab. Like on the paper airplane you made as a kid: bend the trailing edge up a little bit. The million-dollar answer that makes guys like Roncz famous is to define “how much” to bend it up. So, go back to the Rutan Canard Pusher newsletters where Burt defines the criteria, then go get X-Foil or even Roncz’s own tool (the modified Eppler code) and solve the problem the same way Roncz did. It only took Roncz et. al four canards to get the whole thing right – you should be able to do this lesser task with just one (full-span) elevator, maybe one (full-span) elevator modified (slightly) a couple times to tweak it to perfection…. David J. Gall OK, re-read your note, and now I get it: Use Roncz anti-servo trim tab on the stock LS-1 elevator. Right? If so, you are saying mount a servo such as shown on the trailing edge below? 
Cheers, Jay Nope. That’s not what I said. David “Jimmeh” Gall On Dec 16, 2019, at 12:29 PM, Jay Scheevel <jay@...> wrote:
Thanks David, Am aware of the Roncz canard and its implementation on the EZ, but to directly convert the Quickie to that implementation would require re-engineering the elevator actuator. Could do that if starting my canard build over from scratch, but to retrofit on the existing Q2 with the LS-1 already installed would be difficult. The Roncz elevator solution is a sort of a fowler flap and would also require installation of the trailing edge trim. My design is a compromise to be sure, but could be directly retrofit in the existing slot with the same torque tube system as is currently in place and eliminate the sparrow strainer. Don’t know if that will ever happen, but it would be a doable retrofit. Cheers,
Jay Jay, John Roncz came up with the solution to this many years ago. It’s called the “Roncz canard” in the Long-EZ community. It’s an excellent airfoil, but particularly important is what he did to the elevator. The same technique could be used on the LS-1 elevator to mitigate the elevator hinge moment. It can be modeled fairly accurately in X-foil or in Roncz’s modified Eppler airfoil code that he used back then (freely available on the internet). Just gotta tweak it so the elevator floating angle is stable and appropriate for the airplane’s approximate maximum range low cruise airspeed so that if the trim and elevator control systems accidentally disconnect in flight the airplane will be able to continue flight and land using engine power modulation (and reflex if installed) as primary pitch control. Rutan laid out all these requirements in one of the Canard Pusher newsletters in the 1980s. David J. Gall Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do. Seriously, That is an interesting observation. Ideally, you would like your “trim” surfaces, such as the sparrow strainer to be well behaved under all flight conditions, but you have demonstrated that this is not the case. The sparrow strainer flies at a high AOA (negative) all the time, so as to apply a large load to the trailing edge of the elevator, push it into an accelerated condition and boom, you get it to stall. The need for them is entirely the because the aft-1/3 of the LS-1 airfoil has a significant camber on the underside. This camber is by design yielding favorable characteristics when incorporated on a non-articulated airfoil, but when you incorporate an articulated trailing edge (elevator), then the asymmetric force becomes torque on the torque tube and stick deflection instead of into a forward pitching component applied to the rigid wing structure. By countering this effect with the sparrow strainer you actually loose some of the positive characteristics of the pitching moment, and you add a lot of drag. If you could manage it as a pilot, and this is not recommended, the LS-1 would fly better and be more efficient if you could hold the elevator neutral with the stick. But this would require always be pulling lots of aft stick-force. The stick force would be very large in full cruise, and you would never find a hands off condition. It gives you an appreciation for the force that the sparrow strainer supports are experiencing constantly in flight, and why one might potentially depart the aircraft….requiring above average flying skills to recover. I have modeled the forces on the LS-1 elevator and have also designed a modified LS-1 airfoil with the rear portion of the camber removed, where the forces on the redesigned elevator are balanced, (so the sparrow strainer would not be required). I have thought that sometime I would like to build a new set of these redesigned elevators and put them on my plane, but I am just getting comfortable flying with the plans design. On the redesigned airfoil, the lift profile and polars are essentially identical to the LS-1, but what is the big unknown is how the redesigned elevator would impact that stall behavior. Small changes at the trailing edge can be quite impactful on stall, and my modeling method cannot model the complexity of airflow at stall. Cheers, Jay From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Bruce Crain
Sent: Sunday, December 15, 2019 9:32 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil Not sure I really care to know. Either way I will still be aviating in both and won't put any more sound insulation in either one. (more weight) On a side note I have been doing some tuft testing which might be more informational. I have found out that if I pull up the nose and then unload it by pushing forward on the stick my sparrow strainers are stalling on the bottom side. My TriQ will not recover in most instances until I stall out or slow down the airspeed a bunch so that I can pull the stick enough for the strainers to reattach the air underneath them. I just received some vortex generators to put on the bottom of the strainers to do more testing and will hopefully have them in place this week to test. I have noticed in the past that when I do an aileron roll this happens. I have been all though the elevators and ailerons to make sure they were tight and they now are very solid. So then I thought that maybe the wingtip vortices were coming up from the canard and rolling down on the main wing. That never really looked like a good theory. So I installed yarn tufts to see just what was going on. When I flew it started to dawn on me that the elevator was coming up every time I experienced the phenomenon. So I had a good idea that something much simpler was happening and it kept pointing to the sparrow strainer. After talking with Paul Fisher, Jerry Marstall, Sammy Hoskins, and even Scott Swing at Velocity I decided we were looking at a stall. Sure enough when I went up with the tufts in place on the canard and the top and bottom of the sparrow strainers I thought "what if I just pull up and then push forward on the stick could I replicate the problem". When I pulled up and then unloaded the canard by pushing over the sparrow strainers held for a bit and then they relaxed to stick forward an inch or so. I looked out and saw the elevators up about and inch or so and videoed the tufts on the bottom of the strainer disappear and the tufts on the top tufts wrap around the back of the strainer and disappear forward under the strainer! I spoke with Paul, Jerry and Scott again and Scott was freaked but agreed that was what is happening. Bingo! Now I have to fix it so that is where the vortex generator come in. The strainers are a really sensitive trim from dealing with them in the past plus I have them mounted half way outboard on the elevator. I also have 1.2 degrees incidence up on the canard and .8 degrees up on the main wing so we are talking apples to oranges. Sure I could just fly the Q and not go negative on the elevator enough to stall them but I like to do aileron rolls when I am board. I believe you and I experienced the stall when you were getting time in my Q before your first flight. So we educate and experiment and come out improving the species.
---------- Original Message ----------
From: "Jay Scheevel" <jay@...>
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 19:53:06 -0700 If you have an iPhone it has an app available that measures abient noise level. You could give that a try. Sent from my Verizon Wireless 4G LTE DROID
Bruce Crain <jcrain2@...> wrote:
I have not noticed which one is quieter. Will try to do that in the future. Trouble is remembering how loud the other plane is between switches. I will tell Charlie hello for you Dr Mike! Bruce
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001@...>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Mon, 16 Dec 2019 01:37:25 +0000 (UTC)
Hi Mike, My RV6A is noisy. I have a Clark headset modified for active noise reduction but my new Zulu 3 is quieter. I have a Lycoming O-320 E2D 150 with a metal Sensinich prop. I have problem believing a Quickie 200 is quieter. Mike On Sun, Dec 15, 2019 at 7:33 PM, Mike Dwyer I flew in a RV4 recently and I think the inside cockpit of the RV is a lot noisier than a Q200. I'd expect the fiberglass sandwich to dampen some noise. On Sun, Dec 15, 2019 at 8:14 PM Bruce Crain <jcrain2@...> wrote: Sweet! Hope you design a mach .5 airfoil for the Quickie guys Wouldn't that be sweet! I still have my TriQ 200 but I went over to the "Dark Side" when my hanger mate Charlie Calivas sold me his RV 6 for a song and a dance and then proceeded to help me rebuild the engine! My son Jake calls me "2 planes Crain"!
Have a Merry Christmas! Bruce and Honeylamb Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 04:06:52 +0000 (UTC)
Bruce! Good to hear from you as well. Things are great in Wichita. I'm still designing GA airfoils and flying my RV6A and Cessna 120. I went through Emporia two weeks ago and it reminded me of when you, your son, and I got weathered in coming back from the Quickie fly-in at Ottawa. Great hearing from you! My thanks to the Q-List group for letting me "announce" our moving Shuck Airfoil from Yahoo! Groups to Groups.io ! On Sat, Dec 14, 2019 at 9:44 PM, Bruce Crain Good to hear from you again Dr Shuck! How are things in Wichita? Bruce Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 00:24:29 +0000 (UTC) Just to let you know I am in process of moving the former Yahoo! Groups Shuck Airfoil to: I was late getting the mailing list moved over so I would be very thankful if you would post this as many of the Shuck Airfoil group at Yahoo! Groups also were members of Q-List. Moderator of the former Yahoo! Groups Shuck Airfoil
|
|
|
Jay Scheevel
Thanks for the clarification, David. Starting to sound kind of like what I did in my model. I modified the elevator portion of the LS-1 to neutralize the moment on the elevator at zero AOA (plans) . What I did not do is figure out what additional trailing edge modification was necessary to establish the float angle for cruise. I think we are coming into alignment now. By the way, Martin Skiby did what you are describing, but on the fixed trailing edge portion of his main wing in order get the cruise AOA optimized for the two lifting surfaces (on his tri-Q) Cheers, Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of David J. Gall Sent: Monday, December 16, 2019 4:56 PM To: main@Q-List.groups.io Subject: Re: [Q-List] Bruce's tuft study on sparrow strainers Jay, No, but you’re getting MUCH closer. Think full-span fixed trim tab. Like on the paper airplane you made as a kid: bend the trailing edge up a little bit. The million-dollar answer that makes guys like Roncz famous is to define “how much” to bend it up. So, go back to the Rutan Canard Pusher newsletters where Burt defines the criteria, then go get X-Foil or even Roncz’s own tool (the modified Eppler code) and solve the problem the same way Roncz did. It only took Roncz et. al four canards to get the whole thing right – you should be able to do this lesser task with just one (full-span) elevator, maybe one (full-span) elevator modified (slightly) a couple times to tweak it to perfection…. David J. Gall OK, re-read your note, and now I get it: Use Roncz anti-servo trim tab on the stock LS-1 elevator. Right? If so, you are saying mount a servo such as shown on the trailing edge below? 
Cheers, Jay Nope. That’s not what I said. David “Jimmeh” Gall On Dec 16, 2019, at 12:29 PM, Jay Scheevel <jay@...> wrote:
Thanks David, Am aware of the Roncz canard and its implementation on the EZ, but to directly convert the Quickie to that implementation would require re-engineering the elevator actuator. Could do that if starting my canard build over from scratch, but to retrofit on the existing Q2 with the LS-1 already installed would be difficult. The Roncz elevator solution is a sort of a fowler flap and would also require installation of the trailing edge trim. My design is a compromise to be sure, but could be directly retrofit in the existing slot with the same torque tube system as is currently in place and eliminate the sparrow strainer. Don’t know if that will ever happen, but it would be a doable retrofit. Cheers,
Jay Jay, John Roncz came up with the solution to this many years ago. It’s called the “Roncz canard” in the Long-EZ community. It’s an excellent airfoil, but particularly important is what he did to the elevator. The same technique could be used on the LS-1 elevator to mitigate the elevator hinge moment. It can be modeled fairly accurately in X-foil or in Roncz’s modified Eppler airfoil code that he used back then (freely available on the internet). Just gotta tweak it so the elevator floating angle is stable and appropriate for the airplane’s approximate maximum range low cruise airspeed so that if the trim and elevator control systems accidentally disconnect in flight the airplane will be able to continue flight and land using engine power modulation (and reflex if installed) as primary pitch control. Rutan laid out all these requirements in one of the Canard Pusher newsletters in the 1980s. David J. Gall Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do. Seriously, That is an interesting observation. Ideally, you would like your “trim” surfaces, such as the sparrow strainer to be well behaved under all flight conditions, but you have demonstrated that this is not the case. The sparrow strainer flies at a high AOA (negative) all the time, so as to apply a large load to the trailing edge of the elevator, push it into an accelerated condition and boom, you get it to stall. The need for them is entirely the because the aft-1/3 of the LS-1 airfoil has a significant camber on the underside. This camber is by design yielding favorable characteristics when incorporated on a non-articulated airfoil, but when you incorporate an articulated trailing edge (elevator), then the asymmetric force becomes torque on the torque tube and stick deflection instead of into a forward pitching component applied to the rigid wing structure. By countering this effect with the sparrow strainer you actually loose some of the positive characteristics of the pitching moment, and you add a lot of drag. If you could manage it as a pilot, and this is not recommended, the LS-1 would fly better and be more efficient if you could hold the elevator neutral with the stick. But this would require always be pulling lots of aft stick-force. The stick force would be very large in full cruise, and you would never find a hands off condition. It gives you an appreciation for the force that the sparrow strainer supports are experiencing constantly in flight, and why one might potentially depart the aircraft….requiring above average flying skills to recover. I have modeled the forces on the LS-1 elevator and have also designed a modified LS-1 airfoil with the rear portion of the camber removed, where the forces on the redesigned elevator are balanced, (so the sparrow strainer would not be required). I have thought that sometime I would like to build a new set of these redesigned elevators and put them on my plane, but I am just getting comfortable flying with the plans design. On the redesigned airfoil, the lift profile and polars are essentially identical to the LS-1, but what is the big unknown is how the redesigned elevator would impact that stall behavior. Small changes at the trailing edge can be quite impactful on stall, and my modeling method cannot model the complexity of airflow at stall. Cheers, Jay From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Bruce Crain
Sent: Sunday, December 15, 2019 9:32 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil Not sure I really care to know. Either way I will still be aviating in both and won't put any more sound insulation in either one. (more weight) On a side note I have been doing some tuft testing which might be more informational. I have found out that if I pull up the nose and then unload it by pushing forward on the stick my sparrow strainers are stalling on the bottom side. My TriQ will not recover in most instances until I stall out or slow down the airspeed a bunch so that I can pull the stick enough for the strainers to reattach the air underneath them. I just received some vortex generators to put on the bottom of the strainers to do more testing and will hopefully have them in place this week to test. I have noticed in the past that when I do an aileron roll this happens. I have been all though the elevators and ailerons to make sure they were tight and they now are very solid. So then I thought that maybe the wingtip vortices were coming up from the canard and rolling down on the main wing. That never really looked like a good theory. So I installed yarn tufts to see just what was going on. When I flew it started to dawn on me that the elevator was coming up every time I experienced the phenomenon. So I had a good idea that something much simpler was happening and it kept pointing to the sparrow strainer. After talking with Paul Fisher, Jerry Marstall, Sammy Hoskins, and even Scott Swing at Velocity I decided we were looking at a stall. Sure enough when I went up with the tufts in place on the canard and the top and bottom of the sparrow strainers I thought "what if I just pull up and then push forward on the stick could I replicate the problem". When I pulled up and then unloaded the canard by pushing over the sparrow strainers held for a bit and then they relaxed to stick forward an inch or so. I looked out and saw the elevators up about and inch or so and videoed the tufts on the bottom of the strainer disappear and the tufts on the top tufts wrap around the back of the strainer and disappear forward under the strainer! I spoke with Paul, Jerry and Scott again and Scott was freaked but agreed that was what is happening. Bingo! Now I have to fix it so that is where the vortex generator come in. The strainers are a really sensitive trim from dealing with them in the past plus I have them mounted half way outboard on the elevator. I also have 1.2 degrees incidence up on the canard and .8 degrees up on the main wing so we are talking apples to oranges. Sure I could just fly the Q and not go negative on the elevator enough to stall them but I like to do aileron rolls when I am board. I believe you and I experienced the stall when you were getting time in my Q before your first flight. So we educate and experiment and come out improving the species.
---------- Original Message ----------
From: "Jay Scheevel" <jay@...>
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 19:53:06 -0700 If you have an iPhone it has an app available that measures abient noise level. You could give that a try. Sent from my Verizon Wireless 4G LTE DROID
Bruce Crain <jcrain2@...> wrote:
I have not noticed which one is quieter. Will try to do that in the future. Trouble is remembering how loud the other plane is between switches. I will tell Charlie hello for you Dr Mike! Bruce
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001@...>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Mon, 16 Dec 2019 01:37:25 +0000 (UTC)
Hi Mike, My RV6A is noisy. I have a Clark headset modified for active noise reduction but my new Zulu 3 is quieter. I have a Lycoming O-320 E2D 150 with a metal Sensinich prop. I have problem believing a Quickie 200 is quieter. Mike On Sun, Dec 15, 2019 at 7:33 PM, Mike Dwyer I flew in a RV4 recently and I think the inside cockpit of the RV is a lot noisier than a Q200. I'd expect the fiberglass sandwich to dampen some noise. On Sun, Dec 15, 2019 at 8:14 PM Bruce Crain <jcrain2@...> wrote: Sweet! Hope you design a mach .5 airfoil for the Quickie guys Wouldn't that be sweet! I still have my TriQ 200 but I went over to the "Dark Side" when my hanger mate Charlie Calivas sold me his RV 6 for a song and a dance and then proceeded to help me rebuild the engine! My son Jake calls me "2 planes Crain"!
Have a Merry Christmas! Bruce and Honeylamb Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 04:06:52 +0000 (UTC)
Bruce! Good to hear from you as well. Things are great in Wichita. I'm still designing GA airfoils and flying my RV6A and Cessna 120. I went through Emporia two weeks ago and it reminded me of when you, your son, and I got weathered in coming back from the Quickie fly-in at Ottawa. Great hearing from you! My thanks to the Q-List group for letting me "announce" our moving Shuck Airfoil from Yahoo! Groups to Groups.io ! On Sat, Dec 14, 2019 at 9:44 PM, Bruce Crain Good to hear from you again Dr Shuck! How are things in Wichita? Bruce Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 00:24:29 +0000 (UTC) Just to let you know I am in process of moving the former Yahoo! Groups Shuck Airfoil to: I was late getting the mailing list moved over so I would be very thankful if you would post this as many of the Shuck Airfoil group at Yahoo! Groups also were members of Q-List. Moderator of the former Yahoo! Groups Shuck Airfoil
|
|
|
Jay, P.S. - Where’d you find a picture of a Roncz R1145MS with a powered trim tab? THAT was never part of the Roncz canard plans.
- That depiction of the Roncz canard is actually incorrect. The elevator hinge line is in the wrong place. It also looks like it has a Jimmy Durante schnoz (bump on the nose)….
David J. Gall
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of David J. Gall Sent: Monday, December 16, 2019 3:56 PM To: main@Q-List.groups.io Subject: Re: [Q-List] Bruce's tuft study on sparrow strainers Jay, No, but you’re getting MUCH closer. Think full-span fixed trim tab. Like on the paper airplane you made as a kid: bend the trailing edge up a little bit. The million-dollar answer that makes guys like Roncz famous is to define “how much” to bend it up. So, go back to the Rutan Canard Pusher newsletters where Burt defines the criteria, then go get X-Foil or even Roncz’s own tool (the modified Eppler code) and solve the problem the same way Roncz did. It only took Roncz et. al four canards to get the whole thing right – you should be able to do this lesser task with just one (full-span) elevator, maybe one (full-span) elevator modified (slightly) a couple times to tweak it to perfection…. David J. Gall OK, re-read your note, and now I get it: Use Roncz anti-servo trim tab on the stock LS-1 elevator. Right? If so, you are saying mount a servo such as shown on the trailing edge below? 
Cheers, Jay Nope. That’s not what I said. David “Jimmeh” Gall On Dec 16, 2019, at 12:29 PM, Jay Scheevel <jay@...> wrote:
Thanks David, Am aware of the Roncz canard and its implementation on the EZ, but to directly convert the Quickie to that implementation would require re-engineering the elevator actuator. Could do that if starting my canard build over from scratch, but to retrofit on the existing Q2 with the LS-1 already installed would be difficult. The Roncz elevator solution is a sort of a fowler flap and would also require installation of the trailing edge trim. My design is a compromise to be sure, but could be directly retrofit in the existing slot with the same torque tube system as is currently in place and eliminate the sparrow strainer. Don’t know if that will ever happen, but it would be a doable retrofit. Cheers,
Jay Jay, John Roncz came up with the solution to this many years ago. It’s called the “Roncz canard” in the Long-EZ community. It’s an excellent airfoil, but particularly important is what he did to the elevator. The same technique could be used on the LS-1 elevator to mitigate the elevator hinge moment. It can be modeled fairly accurately in X-foil or in Roncz’s modified Eppler airfoil code that he used back then (freely available on the internet). Just gotta tweak it so the elevator floating angle is stable and appropriate for the airplane’s approximate maximum range low cruise airspeed so that if the trim and elevator control systems accidentally disconnect in flight the airplane will be able to continue flight and land using engine power modulation (and reflex if installed) as primary pitch control. Rutan laid out all these requirements in one of the Canard Pusher newsletters in the 1980s. David J. Gall Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do. Seriously, That is an interesting observation. Ideally, you would like your “trim” surfaces, such as the sparrow strainer to be well behaved under all flight conditions, but you have demonstrated that this is not the case. The sparrow strainer flies at a high AOA (negative) all the time, so as to apply a large load to the trailing edge of the elevator, push it into an accelerated condition and boom, you get it to stall. The need for them is entirely the because the aft-1/3 of the LS-1 airfoil has a significant camber on the underside. This camber is by design yielding favorable characteristics when incorporated on a non-articulated airfoil, but when you incorporate an articulated trailing edge (elevator), then the asymmetric force becomes torque on the torque tube and stick deflection instead of into a forward pitching component applied to the rigid wing structure. By countering this effect with the sparrow strainer you actually loose some of the positive characteristics of the pitching moment, and you add a lot of drag. If you could manage it as a pilot, and this is not recommended, the LS-1 would fly better and be more efficient if you could hold the elevator neutral with the stick. But this would require always be pulling lots of aft stick-force. The stick force would be very large in full cruise, and you would never find a hands off condition. It gives you an appreciation for the force that the sparrow strainer supports are experiencing constantly in flight, and why one might potentially depart the aircraft….requiring above average flying skills to recover. I have modeled the forces on the LS-1 elevator and have also designed a modified LS-1 airfoil with the rear portion of the camber removed, where the forces on the redesigned elevator are balanced, (so the sparrow strainer would not be required). I have thought that sometime I would like to build a new set of these redesigned elevators and put them on my plane, but I am just getting comfortable flying with the plans design. On the redesigned airfoil, the lift profile and polars are essentially identical to the LS-1, but what is the big unknown is how the redesigned elevator would impact that stall behavior. Small changes at the trailing edge can be quite impactful on stall, and my modeling method cannot model the complexity of airflow at stall. Cheers, Jay From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Bruce Crain
Sent: Sunday, December 15, 2019 9:32 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil Not sure I really care to know. Either way I will still be aviating in both and won't put any more sound insulation in either one. (more weight) On a side note I have been doing some tuft testing which might be more informational. I have found out that if I pull up the nose and then unload it by pushing forward on the stick my sparrow strainers are stalling on the bottom side. My TriQ will not recover in most instances until I stall out or slow down the airspeed a bunch so that I can pull the stick enough for the strainers to reattach the air underneath them. I just received some vortex generators to put on the bottom of the strainers to do more testing and will hopefully have them in place this week to test. I have noticed in the past that when I do an aileron roll this happens. I have been all though the elevators and ailerons to make sure they were tight and they now are very solid. So then I thought that maybe the wingtip vortices were coming up from the canard and rolling down on the main wing. That never really looked like a good theory. So I installed yarn tufts to see just what was going on. When I flew it started to dawn on me that the elevator was coming up every time I experienced the phenomenon. So I had a good idea that something much simpler was happening and it kept pointing to the sparrow strainer. After talking with Paul Fisher, Jerry Marstall, Sammy Hoskins, and even Scott Swing at Velocity I decided we were looking at a stall. Sure enough when I went up with the tufts in place on the canard and the top and bottom of the sparrow strainers I thought "what if I just pull up and then push forward on the stick could I replicate the problem". When I pulled up and then unloaded the canard by pushing over the sparrow strainers held for a bit and then they relaxed to stick forward an inch or so. I looked out and saw the elevators up about and inch or so and videoed the tufts on the bottom of the strainer disappear and the tufts on the top tufts wrap around the back of the strainer and disappear forward under the strainer! I spoke with Paul, Jerry and Scott again and Scott was freaked but agreed that was what is happening. Bingo! Now I have to fix it so that is where the vortex generator come in. The strainers are a really sensitive trim from dealing with them in the past plus I have them mounted half way outboard on the elevator. I also have 1.2 degrees incidence up on the canard and .8 degrees up on the main wing so we are talking apples to oranges. Sure I could just fly the Q and not go negative on the elevator enough to stall them but I like to do aileron rolls when I am board. I believe you and I experienced the stall when you were getting time in my Q before your first flight. So we educate and experiment and come out improving the species.
---------- Original Message ----------
From: "Jay Scheevel" <jay@...>
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 19:53:06 -0700 If you have an iPhone it has an app available that measures abient noise level. You could give that a try. Sent from my Verizon Wireless 4G LTE DROID
Bruce Crain <jcrain2@...> wrote:
I have not noticed which one is quieter. Will try to do that in the future. Trouble is remembering how loud the other plane is between switches. I will tell Charlie hello for you Dr Mike! Bruce
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001@...>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Mon, 16 Dec 2019 01:37:25 +0000 (UTC)
Hi Mike, My RV6A is noisy. I have a Clark headset modified for active noise reduction but my new Zulu 3 is quieter. I have a Lycoming O-320 E2D 150 with a metal Sensinich prop. I have problem believing a Quickie 200 is quieter. Mike On Sun, Dec 15, 2019 at 7:33 PM, Mike Dwyer I flew in a RV4 recently and I think the inside cockpit of the RV is a lot noisier than a Q200. I'd expect the fiberglass sandwich to dampen some noise. On Sun, Dec 15, 2019 at 8:14 PM Bruce Crain <jcrain2@...> wrote: Sweet! Hope you design a mach .5 airfoil for the Quickie guys Wouldn't that be sweet! I still have my TriQ 200 but I went over to the "Dark Side" when my hanger mate Charlie Calivas sold me his RV 6 for a song and a dance and then proceeded to help me rebuild the engine! My son Jake calls me "2 planes Crain"!
Have a Merry Christmas! Bruce and Honeylamb Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 04:06:52 +0000 (UTC)
Bruce! Good to hear from you as well. Things are great in Wichita. I'm still designing GA airfoils and flying my RV6A and Cessna 120. I went through Emporia two weeks ago and it reminded me of when you, your son, and I got weathered in coming back from the Quickie fly-in at Ottawa. Great hearing from you! My thanks to the Q-List group for letting me "announce" our moving Shuck Airfoil from Yahoo! Groups to Groups.io ! On Sat, Dec 14, 2019 at 9:44 PM, Bruce Crain Good to hear from you again Dr Shuck! How are things in Wichita? Bruce Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 00:24:29 +0000 (UTC) Just to let you know I am in process of moving the former Yahoo! Groups Shuck Airfoil to: I was late getting the mailing list moved over so I would be very thankful if you would post this as many of the Shuck Airfoil group at Yahoo! Groups also were members of Q-List. Moderator of the former Yahoo! Groups Shuck Airfoil
|
|
|
Jay, No, but you’re getting MUCH closer. Think full-span fixed trim tab. Like on the paper airplane you made as a kid: bend the trailing edge up a little bit. The million-dollar answer that makes guys like Roncz famous is to define “how much” to bend it up. So, go back to the Rutan Canard Pusher newsletters where Burt defines the criteria, then go get X-Foil or even Roncz’s own tool (the modified Eppler code) and solve the problem the same way Roncz did. It only took Roncz et. al four canards to get the whole thing right – you should be able to do this lesser task with just one (full-span) elevator, maybe one (full-span) elevator modified (slightly) a couple times to tweak it to perfection…. David J. Gall
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Jay Scheevel Sent: Monday, December 16, 2019 3:46 PM To: main@Q-List.groups.io Subject: Re: [Q-List] Bruce's tuft study on sparrow strainers OK, re-read your note, and now I get it: Use Roncz anti-servo trim tab on the stock LS-1 elevator. Right? If so, you are saying mount a servo such as shown on the trailing edge below? 
Cheers, Jay Nope. That’s not what I said. David “Jimmeh” Gall On Dec 16, 2019, at 12:29 PM, Jay Scheevel <jay@...> wrote:
Thanks David, Am aware of the Roncz canard and its implementation on the EZ, but to directly convert the Quickie to that implementation would require re-engineering the elevator actuator. Could do that if starting my canard build over from scratch, but to retrofit on the existing Q2 with the LS-1 already installed would be difficult. The Roncz elevator solution is a sort of a fowler flap and would also require installation of the trailing edge trim. My design is a compromise to be sure, but could be directly retrofit in the existing slot with the same torque tube system as is currently in place and eliminate the sparrow strainer. Don’t know if that will ever happen, but it would be a doable retrofit. Cheers,
Jay Jay, John Roncz came up with the solution to this many years ago. It’s called the “Roncz canard” in the Long-EZ community. It’s an excellent airfoil, but particularly important is what he did to the elevator. The same technique could be used on the LS-1 elevator to mitigate the elevator hinge moment. It can be modeled fairly accurately in X-foil or in Roncz’s modified Eppler airfoil code that he used back then (freely available on the internet). Just gotta tweak it so the elevator floating angle is stable and appropriate for the airplane’s approximate maximum range low cruise airspeed so that if the trim and elevator control systems accidentally disconnect in flight the airplane will be able to continue flight and land using engine power modulation (and reflex if installed) as primary pitch control. Rutan laid out all these requirements in one of the Canard Pusher newsletters in the 1980s. David J. Gall Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do. Seriously, That is an interesting observation. Ideally, you would like your “trim” surfaces, such as the sparrow strainer to be well behaved under all flight conditions, but you have demonstrated that this is not the case. The sparrow strainer flies at a high AOA (negative) all the time, so as to apply a large load to the trailing edge of the elevator, push it into an accelerated condition and boom, you get it to stall. The need for them is entirely the because the aft-1/3 of the LS-1 airfoil has a significant camber on the underside. This camber is by design yielding favorable characteristics when incorporated on a non-articulated airfoil, but when you incorporate an articulated trailing edge (elevator), then the asymmetric force becomes torque on the torque tube and stick deflection instead of into a forward pitching component applied to the rigid wing structure. By countering this effect with the sparrow strainer you actually loose some of the positive characteristics of the pitching moment, and you add a lot of drag. If you could manage it as a pilot, and this is not recommended, the LS-1 would fly better and be more efficient if you could hold the elevator neutral with the stick. But this would require always be pulling lots of aft stick-force. The stick force would be very large in full cruise, and you would never find a hands off condition. It gives you an appreciation for the force that the sparrow strainer supports are experiencing constantly in flight, and why one might potentially depart the aircraft….requiring above average flying skills to recover. I have modeled the forces on the LS-1 elevator and have also designed a modified LS-1 airfoil with the rear portion of the camber removed, where the forces on the redesigned elevator are balanced, (so the sparrow strainer would not be required). I have thought that sometime I would like to build a new set of these redesigned elevators and put them on my plane, but I am just getting comfortable flying with the plans design. On the redesigned airfoil, the lift profile and polars are essentially identical to the LS-1, but what is the big unknown is how the redesigned elevator would impact that stall behavior. Small changes at the trailing edge can be quite impactful on stall, and my modeling method cannot model the complexity of airflow at stall. Cheers, Jay From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Bruce Crain
Sent: Sunday, December 15, 2019 9:32 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil Not sure I really care to know. Either way I will still be aviating in both and won't put any more sound insulation in either one. (more weight) On a side note I have been doing some tuft testing which might be more informational. I have found out that if I pull up the nose and then unload it by pushing forward on the stick my sparrow strainers are stalling on the bottom side. My TriQ will not recover in most instances until I stall out or slow down the airspeed a bunch so that I can pull the stick enough for the strainers to reattach the air underneath them. I just received some vortex generators to put on the bottom of the strainers to do more testing and will hopefully have them in place this week to test. I have noticed in the past that when I do an aileron roll this happens. I have been all though the elevators and ailerons to make sure they were tight and they now are very solid. So then I thought that maybe the wingtip vortices were coming up from the canard and rolling down on the main wing. That never really looked like a good theory. So I installed yarn tufts to see just what was going on. When I flew it started to dawn on me that the elevator was coming up every time I experienced the phenomenon. So I had a good idea that something much simpler was happening and it kept pointing to the sparrow strainer. After talking with Paul Fisher, Jerry Marstall, Sammy Hoskins, and even Scott Swing at Velocity I decided we were looking at a stall. Sure enough when I went up with the tufts in place on the canard and the top and bottom of the sparrow strainers I thought "what if I just pull up and then push forward on the stick could I replicate the problem". When I pulled up and then unloaded the canard by pushing over the sparrow strainers held for a bit and then they relaxed to stick forward an inch or so. I looked out and saw the elevators up about and inch or so and videoed the tufts on the bottom of the strainer disappear and the tufts on the top tufts wrap around the back of the strainer and disappear forward under the strainer! I spoke with Paul, Jerry and Scott again and Scott was freaked but agreed that was what is happening. Bingo! Now I have to fix it so that is where the vortex generator come in. The strainers are a really sensitive trim from dealing with them in the past plus I have them mounted half way outboard on the elevator. I also have 1.2 degrees incidence up on the canard and .8 degrees up on the main wing so we are talking apples to oranges. Sure I could just fly the Q and not go negative on the elevator enough to stall them but I like to do aileron rolls when I am board. I believe you and I experienced the stall when you were getting time in my Q before your first flight. So we educate and experiment and come out improving the species.
---------- Original Message ----------
From: "Jay Scheevel" <jay@...>
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 19:53:06 -0700 If you have an iPhone it has an app available that measures abient noise level. You could give that a try. Sent from my Verizon Wireless 4G LTE DROID
Bruce Crain <jcrain2@...> wrote:
I have not noticed which one is quieter. Will try to do that in the future. Trouble is remembering how loud the other plane is between switches. I will tell Charlie hello for you Dr Mike! Bruce
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001@...>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Mon, 16 Dec 2019 01:37:25 +0000 (UTC)
Hi Mike, My RV6A is noisy. I have a Clark headset modified for active noise reduction but my new Zulu 3 is quieter. I have a Lycoming O-320 E2D 150 with a metal Sensinich prop. I have problem believing a Quickie 200 is quieter. Mike On Sun, Dec 15, 2019 at 7:33 PM, Mike Dwyer I flew in a RV4 recently and I think the inside cockpit of the RV is a lot noisier than a Q200. I'd expect the fiberglass sandwich to dampen some noise. On Sun, Dec 15, 2019 at 8:14 PM Bruce Crain <jcrain2@...> wrote: Sweet! Hope you design a mach .5 airfoil for the Quickie guys Wouldn't that be sweet! I still have my TriQ 200 but I went over to the "Dark Side" when my hanger mate Charlie Calivas sold me his RV 6 for a song and a dance and then proceeded to help me rebuild the engine! My son Jake calls me "2 planes Crain"!
Have a Merry Christmas! Bruce and Honeylamb Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 04:06:52 +0000 (UTC)
Bruce! Good to hear from you as well. Things are great in Wichita. I'm still designing GA airfoils and flying my RV6A and Cessna 120. I went through Emporia two weeks ago and it reminded me of when you, your son, and I got weathered in coming back from the Quickie fly-in at Ottawa. Great hearing from you! My thanks to the Q-List group for letting me "announce" our moving Shuck Airfoil from Yahoo! Groups to Groups.io ! On Sat, Dec 14, 2019 at 9:44 PM, Bruce Crain Good to hear from you again Dr Shuck! How are things in Wichita? Bruce Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 00:24:29 +0000 (UTC) Just to let you know I am in process of moving the former Yahoo! Groups Shuck Airfoil to: I was late getting the mailing list moved over so I would be very thankful if you would post this as many of the Shuck Airfoil group at Yahoo! Groups also were members of Q-List. Moderator of the former Yahoo! Groups Shuck Airfoil
|
|
|
Jay Scheevel
OK, re-read your note, and now I get it: Use Roncz anti-servo trim tab on the stock LS-1 elevator. Right? If so, you are saying mount a servo such as shown on the trailing edge below? 
Cheers, Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of David J. Gall Sent: Monday, December 16, 2019 4:15 PM To: main@q-list.groups.io Subject: Re: [Q-List] Bruce's tuft study on sparrow strainers Nope. That’s not what I said. David “Jimmeh” Gall
On Dec 16, 2019, at 12:29 PM, Jay Scheevel <jay@...> wrote:
Thanks David, Am aware of the Roncz canard and its implementation on the EZ, but to directly convert the Quickie to that implementation would require re-engineering the elevator actuator. Could do that if starting my canard build over from scratch, but to retrofit on the existing Q2 with the LS-1 already installed would be difficult. The Roncz elevator solution is a sort of a fowler flap and would also require installation of the trailing edge trim. My design is a compromise to be sure, but could be directly retrofit in the existing slot with the same torque tube system as is currently in place and eliminate the sparrow strainer. Don’t know if that will ever happen, but it would be a doable retrofit. Cheers,
Jay Jay, John Roncz came up with the solution to this many years ago. It’s called the “Roncz canard” in the Long-EZ community. It’s an excellent airfoil, but particularly important is what he did to the elevator. The same technique could be used on the LS-1 elevator to mitigate the elevator hinge moment. It can be modeled fairly accurately in X-foil or in Roncz’s modified Eppler airfoil code that he used back then (freely available on the internet). Just gotta tweak it so the elevator floating angle is stable and appropriate for the airplane’s approximate maximum range low cruise airspeed so that if the trim and elevator control systems accidentally disconnect in flight the airplane will be able to continue flight and land using engine power modulation (and reflex if installed) as primary pitch control. Rutan laid out all these requirements in one of the Canard Pusher newsletters in the 1980s. David J. Gall Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do. Seriously, That is an interesting observation. Ideally, you would like your “trim” surfaces, such as the sparrow strainer to be well behaved under all flight conditions, but you have demonstrated that this is not the case. The sparrow strainer flies at a high AOA (negative) all the time, so as to apply a large load to the trailing edge of the elevator, push it into an accelerated condition and boom, you get it to stall. The need for them is entirely the because the aft-1/3 of the LS-1 airfoil has a significant camber on the underside. This camber is by design yielding favorable characteristics when incorporated on a non-articulated airfoil, but when you incorporate an articulated trailing edge (elevator), then the asymmetric force becomes torque on the torque tube and stick deflection instead of into a forward pitching component applied to the rigid wing structure. By countering this effect with the sparrow strainer you actually loose some of the positive characteristics of the pitching moment, and you add a lot of drag. If you could manage it as a pilot, and this is not recommended, the LS-1 would fly better and be more efficient if you could hold the elevator neutral with the stick. But this would require always be pulling lots of aft stick-force. The stick force would be very large in full cruise, and you would never find a hands off condition. It gives you an appreciation for the force that the sparrow strainer supports are experiencing constantly in flight, and why one might potentially depart the aircraft….requiring above average flying skills to recover. I have modeled the forces on the LS-1 elevator and have also designed a modified LS-1 airfoil with the rear portion of the camber removed, where the forces on the redesigned elevator are balanced, (so the sparrow strainer would not be required). I have thought that sometime I would like to build a new set of these redesigned elevators and put them on my plane, but I am just getting comfortable flying with the plans design. On the redesigned airfoil, the lift profile and polars are essentially identical to the LS-1, but what is the big unknown is how the redesigned elevator would impact that stall behavior. Small changes at the trailing edge can be quite impactful on stall, and my modeling method cannot model the complexity of airflow at stall. Cheers, Jay From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Bruce Crain
Sent: Sunday, December 15, 2019 9:32 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil Not sure I really care to know. Either way I will still be aviating in both and won't put any more sound insulation in either one. (more weight) On a side note I have been doing some tuft testing which might be more informational. I have found out that if I pull up the nose and then unload it by pushing forward on the stick my sparrow strainers are stalling on the bottom side. My TriQ will not recover in most instances until I stall out or slow down the airspeed a bunch so that I can pull the stick enough for the strainers to reattach the air underneath them. I just received some vortex generators to put on the bottom of the strainers to do more testing and will hopefully have them in place this week to test. I have noticed in the past that when I do an aileron roll this happens. I have been all though the elevators and ailerons to make sure they were tight and they now are very solid. So then I thought that maybe the wingtip vortices were coming up from the canard and rolling down on the main wing. That never really looked like a good theory. So I installed yarn tufts to see just what was going on. When I flew it started to dawn on me that the elevator was coming up every time I experienced the phenomenon. So I had a good idea that something much simpler was happening and it kept pointing to the sparrow strainer. After talking with Paul Fisher, Jerry Marstall, Sammy Hoskins, and even Scott Swing at Velocity I decided we were looking at a stall. Sure enough when I went up with the tufts in place on the canard and the top and bottom of the sparrow strainers I thought "what if I just pull up and then push forward on the stick could I replicate the problem". When I pulled up and then unloaded the canard by pushing over the sparrow strainers held for a bit and then they relaxed to stick forward an inch or so. I looked out and saw the elevators up about and inch or so and videoed the tufts on the bottom of the strainer disappear and the tufts on the top tufts wrap around the back of the strainer and disappear forward under the strainer! I spoke with Paul, Jerry and Scott again and Scott was freaked but agreed that was what is happening. Bingo! Now I have to fix it so that is where the vortex generator come in. The strainers are a really sensitive trim from dealing with them in the past plus I have them mounted half way outboard on the elevator. I also have 1.2 degrees incidence up on the canard and .8 degrees up on the main wing so we are talking apples to oranges. Sure I could just fly the Q and not go negative on the elevator enough to stall them but I like to do aileron rolls when I am board. I believe you and I experienced the stall when you were getting time in my Q before your first flight. So we educate and experiment and come out improving the species.
---------- Original Message ----------
From: "Jay Scheevel" <jay@...>
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 19:53:06 -0700 If you have an iPhone it has an app available that measures abient noise level. You could give that a try. Sent from my Verizon Wireless 4G LTE DROID
Bruce Crain <jcrain2@...> wrote:
I have not noticed which one is quieter. Will try to do that in the future. Trouble is remembering how loud the other plane is between switches. I will tell Charlie hello for you Dr Mike! Bruce
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001@...>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Mon, 16 Dec 2019 01:37:25 +0000 (UTC)
Hi Mike, My RV6A is noisy. I have a Clark headset modified for active noise reduction but my new Zulu 3 is quieter. I have a Lycoming O-320 E2D 150 with a metal Sensinich prop. I have problem believing a Quickie 200 is quieter. Mike On Sun, Dec 15, 2019 at 7:33 PM, Mike Dwyer I flew in a RV4 recently and I think the inside cockpit of the RV is a lot noisier than a Q200. I'd expect the fiberglass sandwich to dampen some noise. On Sun, Dec 15, 2019 at 8:14 PM Bruce Crain <jcrain2@...> wrote: Sweet! Hope you design a mach .5 airfoil for the Quickie guys Wouldn't that be sweet! I still have my TriQ 200 but I went over to the "Dark Side" when my hanger mate Charlie Calivas sold me his RV 6 for a song and a dance and then proceeded to help me rebuild the engine! My son Jake calls me "2 planes Crain"!
Have a Merry Christmas! Bruce and Honeylamb Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 04:06:52 +0000 (UTC)
Bruce! Good to hear from you as well. Things are great in Wichita. I'm still designing GA airfoils and flying my RV6A and Cessna 120. I went through Emporia two weeks ago and it reminded me of when you, your son, and I got weathered in coming back from the Quickie fly-in at Ottawa. Great hearing from you! My thanks to the Q-List group for letting me "announce" our moving Shuck Airfoil from Yahoo! Groups to Groups.io ! On Sat, Dec 14, 2019 at 9:44 PM, Bruce Crain Good to hear from you again Dr Shuck! How are things in Wichita? Bruce Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 00:24:29 +0000 (UTC) Just to let you know I am in process of moving the former Yahoo! Groups Shuck Airfoil to: I was late getting the mailing list moved over so I would be very thankful if you would post this as many of the Shuck Airfoil group at Yahoo! Groups also were members of Q-List. Moderator of the former Yahoo! Groups Shuck Airfoil
|
|
|
Jay,
Nope. That’s not what I said.
Not even close.
David “Jimmeh” Gall
On Dec 16, 2019, at 12:29 PM, Jay Scheevel <jay@...> wrote:
Thanks David, Am aware of the Roncz canard and its implementation on the EZ, but to directly convert the Quickie to that implementation would require re-engineering the elevator actuator. Could do that if starting my canard build over from scratch, but to retrofit on the existing Q2 with the LS-1 already installed would be difficult. The Roncz elevator solution is a sort of a fowler flap and would also require installation of the trailing edge trim. My design is a compromise to be sure, but could be directly retrofit in the existing slot with the same torque tube system as is currently in place and eliminate the sparrow strainer. Don’t know if that will ever happen, but it would be a doable retrofit. Cheers,
Jay From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of David J. Gall
Sent: Monday, December 16, 2019 12:49 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Bruce's tuft study on sparrow strainers Jay, John Roncz came up with the solution to this many years ago. It’s called the “Roncz canard” in the Long-EZ community. It’s an excellent airfoil, but particularly important is what he did to the elevator. The same technique could be used on the LS-1 elevator to mitigate the elevator hinge moment. It can be modeled fairly accurately in X-foil or in Roncz’s modified Eppler airfoil code that he used back then (freely available on the internet). Just gotta tweak it so the elevator floating angle is stable and appropriate for the airplane’s approximate maximum range low cruise airspeed so that if the trim and elevator control systems accidentally disconnect in flight the airplane will be able to continue flight and land using engine power modulation (and reflex if installed) as primary pitch control. Rutan laid out all these requirements in one of the Canard Pusher newsletters in the 1980s. David J. Gall Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do. Seriously, That is an interesting observation. Ideally, you would like your “trim” surfaces, such as the sparrow strainer to be well behaved under all flight conditions, but you have demonstrated that this is not the case. The sparrow strainer flies at a high AOA (negative) all the time, so as to apply a large load to the trailing edge of the elevator, push it into an accelerated condition and boom, you get it to stall. The need for them is entirely the because the aft-1/3 of the LS-1 airfoil has a significant camber on the underside. This camber is by design yielding favorable characteristics when incorporated on a non-articulated airfoil, but when you incorporate an articulated trailing edge (elevator), then the asymmetric force becomes torque on the torque tube and stick deflection instead of into a forward pitching component applied to the rigid wing structure. By countering this effect with the sparrow strainer you actually loose some of the positive characteristics of the pitching moment, and you add a lot of drag. If you could manage it as a pilot, and this is not recommended, the LS-1 would fly better and be more efficient if you could hold the elevator neutral with the stick. But this would require always be pulling lots of aft stick-force. The stick force would be very large in full cruise, and you would never find a hands off condition. It gives you an appreciation for the force that the sparrow strainer supports are experiencing constantly in flight, and why one might potentially depart the aircraft….requiring above average flying skills to recover. I have modeled the forces on the LS-1 elevator and have also designed a modified LS-1 airfoil with the rear portion of the camber removed, where the forces on the redesigned elevator are balanced, (so the sparrow strainer would not be required). I have thought that sometime I would like to build a new set of these redesigned elevators and put them on my plane, but I am just getting comfortable flying with the plans design. On the redesigned airfoil, the lift profile and polars are essentially identical to the LS-1, but what is the big unknown is how the redesigned elevator would impact that stall behavior. Small changes at the trailing edge can be quite impactful on stall, and my modeling method cannot model the complexity of airflow at stall. Cheers, Jay From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Bruce Crain
Sent: Sunday, December 15, 2019 9:32 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil Not sure I really care to know. Either way I will still be aviating in both and won't put any more sound insulation in either one. (more weight) On a side note I have been doing some tuft testing which might be more informational. I have found out that if I pull up the nose and then unload it by pushing forward on the stick my sparrow strainers are stalling on the bottom side. My TriQ will not recover in most instances until I stall out or slow down the airspeed a bunch so that I can pull the stick enough for the strainers to reattach the air underneath them. I just received some vortex generators to put on the bottom of the strainers to do more testing and will hopefully have them in place this week to test. I have noticed in the past that when I do an aileron roll this happens. I have been all though the elevators and ailerons to make sure they were tight and they now are very solid. So then I thought that maybe the wingtip vortices were coming up from the canard and rolling down on the main wing. That never really looked like a good theory. So I installed yarn tufts to see just what was going on. When I flew it started to dawn on me that the elevator was coming up every time I experienced the phenomenon. So I had a good idea that something much simpler was happening and it kept pointing to the sparrow strainer. After talking with Paul Fisher, Jerry Marstall, Sammy Hoskins, and even Scott Swing at Velocity I decided we were looking at a stall. Sure enough when I went up with the tufts in place on the canard and the top and bottom of the sparrow strainers I thought "what if I just pull up and then push forward on the stick could I replicate the problem". When I pulled up and then unloaded the canard by pushing over the sparrow strainers held for a bit and then they relaxed to stick forward an inch or so. I looked out and saw the elevators up about and inch or so and videoed the tufts on the bottom of the strainer disappear and the tufts on the top tufts wrap around the back of the strainer and disappear forward under the strainer! I spoke with Paul, Jerry and Scott again and Scott was freaked but agreed that was what is happening. Bingo! Now I have to fix it so that is where the vortex generator come in. The strainers are a really sensitive trim from dealing with them in the past plus I have them mounted half way outboard on the elevator. I also have 1.2 degrees incidence up on the canard and .8 degrees up on the main wing so we are talking apples to oranges. Sure I could just fly the Q and not go negative on the elevator enough to stall them but I like to do aileron rolls when I am board. I believe you and I experienced the stall when you were getting time in my Q before your first flight. So we educate and experiment and come out improving the species.
---------- Original Message ----------
From: "Jay Scheevel" <jay@...>
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 19:53:06 -0700 If you have an iPhone it has an app available that measures abient noise level. You could give that a try. Sent from my Verizon Wireless 4G LTE DROID
Bruce Crain <jcrain2@...> wrote:
I have not noticed which one is quieter. Will try to do that in the future. Trouble is remembering how loud the other plane is between switches. I will tell Charlie hello for you Dr Mike! Bruce
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001@...>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Mon, 16 Dec 2019 01:37:25 +0000 (UTC)
Hi Mike, My RV6A is noisy. I have a Clark headset modified for active noise reduction but my new Zulu 3 is quieter. I have a Lycoming O-320 E2D 150 with a metal Sensinich prop. I have problem believing a Quickie 200 is quieter. Mike On Sun, Dec 15, 2019 at 7:33 PM, Mike Dwyer I flew in a RV4 recently and I think the inside cockpit of the RV is a lot noisier than a Q200. I'd expect the fiberglass sandwich to dampen some noise. On Sun, Dec 15, 2019 at 8:14 PM Bruce Crain <jcrain2@...> wrote: Sweet! Hope you design a mach .5 airfoil for the Quickie guys Wouldn't that be sweet! I still have my TriQ 200 but I went over to the "Dark Side" when my hanger mate Charlie Calivas sold me his RV 6 for a song and a dance and then proceeded to help me rebuild the engine! My son Jake calls me "2 planes Crain"!
Have a Merry Christmas! Bruce and Honeylamb Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 04:06:52 +0000 (UTC)
Bruce! Good to hear from you as well. Things are great in Wichita. I'm still designing GA airfoils and flying my RV6A and Cessna 120. I went through Emporia two weeks ago and it reminded me of when you, your son, and I got weathered in coming back from the Quickie fly-in at Ottawa. Great hearing from you! My thanks to the Q-List group for letting me "announce" our moving Shuck Airfoil from Yahoo! Groups to Groups.io ! On Sat, Dec 14, 2019 at 9:44 PM, Bruce Crain Good to hear from you again Dr Shuck! How are things in Wichita? Bruce Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 00:24:29 +0000 (UTC) Just to let you know I am in process of moving the former Yahoo! Groups Shuck Airfoil to: I was late getting the mailing list moved over so I would be very thankful if you would post this as many of the Shuck Airfoil group at Yahoo! Groups also were members of Q-List. Moderator of the former Yahoo! Groups Shuck Airfoil
|
|
|
Jeffrey Bevilacqua <jlbevila@...>
Thanks Charlie and Jay. Im now set up for my new Dragonfly account.
On Monday, December 16, 2019, 12:48:17 PM PST, One Sky Dog via Groups.Io <oneskydog@...> wrote:
Jeff,
I make the side plates with a notch > that fits over the trailing edge of th=
e elevator 1/8=E2=80=9D or so. That loads the adhesive in compression and sh=
ear like it is supposed to be loaded. Just gluing them on the bottom puts th=
e adhesive in peeling tension. Glue is not strong in peel.
Clean the surface , use fine sandpaper to sand to the glass on the elevator b=
ottom, use structural epoxy filled with flox for no drip fillets to bond the=
m on.
There is a Dragonfly group=20
https://dragonflylist.groups.io/g/main/photos?p=3Dcreated,,,20,2,80,0
Charlie Johnson
On Dec 16, 2019, at 10:23 AM, Jeffrey Bevilacqua via Groups.Io < jlbevila@...> wrote:
Justa quick question. Can anyone recommend a reliable adhesive to attach the Sparrow Strainers to the elevator considering the constant high loads. Thanks. Jeff Bevilacqua DF MK H.
On Monday, December 16, 2019, 09:15:41 AM PST, One Sky Dog via Groups.Io < oneskydog@...> wrote:
Bruce roll the RV problem solved.
I know Tex Johnson rolled a 707 so why not a Q?
Milk stool pilot On Dec 16, 2019, at 9:09 AM, Jay Scheevel < jay@...> wrote:
Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do.
|
|
|
One Sky Dog
Jeff,
I make the side plates with a notch > that fits over the trailing edge of th=
e elevator 1/8=E2=80=9D or so. That loads the adhesive in compression and sh=
ear like it is supposed to be loaded. Just gluing them on the bottom puts th=
e adhesive in peeling tension. Glue is not strong in peel.
Clean the surface , use fine sandpaper to sand to the glass on the elevator b=
ottom, use structural epoxy filled with flox for no drip fillets to bond the=
m on.
There is a Dragonfly group=20
https://dragonflylist.groups.io/g/main/photos?p=3Dcreated,,,20,2,80,0
Charlie Johnson
toggle quoted message
Show quoted text
On Dec 16, 2019, at 10:23 AM, Jeffrey Bevilacqua via Groups.Io < jlbevila@...> wrote:
Justa quick question. Can anyone recommend a reliable adhesive to attach the Sparrow Strainers to the elevator considering the constant high loads. Thanks. Jeff Bevilacqua DF MK H.
On Monday, December 16, 2019, 09:15:41 AM PST, One Sky Dog via Groups.Io < oneskydog@...> wrote:
Bruce roll the RV problem solved.
I know Tex Johnson rolled a 707 so why not a Q?
Milk stool pilot On Dec 16, 2019, at 9:09 AM, Jay Scheevel < jay@...> wrote:
Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do.
|
|
|
Jay Scheevel
Thanks David, Am aware of the Roncz canard and its implementation on the EZ, but to directly convert the Quickie to that implementation would require re-engineering the elevator actuator. Could do that if starting my canard build over from scratch, but to retrofit on the existing Q2 with the LS-1 already installed would be difficult. The Roncz elevator solution is a sort of a fowler flap and would also require installation of the trailing edge trim. My design is a compromise to be sure, but could be directly retrofit in the existing slot with the same torque tube system as is currently in place and eliminate the sparrow strainer. Don’t know if that will ever happen, but it would be a doable retrofit. Cheers,
Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of David J. Gall Sent: Monday, December 16, 2019 12:49 PM To: main@Q-List.groups.io Subject: Re: [Q-List] Bruce's tuft study on sparrow strainers Jay, John Roncz came up with the solution to this many years ago. It’s called the “Roncz canard” in the Long-EZ community. It’s an excellent airfoil, but particularly important is what he did to the elevator. The same technique could be used on the LS-1 elevator to mitigate the elevator hinge moment. It can be modeled fairly accurately in X-foil or in Roncz’s modified Eppler airfoil code that he used back then (freely available on the internet). Just gotta tweak it so the elevator floating angle is stable and appropriate for the airplane’s approximate maximum range low cruise airspeed so that if the trim and elevator control systems accidentally disconnect in flight the airplane will be able to continue flight and land using engine power modulation (and reflex if installed) as primary pitch control. Rutan laid out all these requirements in one of the Canard Pusher newsletters in the 1980s. David J. Gall Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do. Seriously, That is an interesting observation. Ideally, you would like your “trim” surfaces, such as the sparrow strainer to be well behaved under all flight conditions, but you have demonstrated that this is not the case. The sparrow strainer flies at a high AOA (negative) all the time, so as to apply a large load to the trailing edge of the elevator, push it into an accelerated condition and boom, you get it to stall. The need for them is entirely the because the aft-1/3 of the LS-1 airfoil has a significant camber on the underside. This camber is by design yielding favorable characteristics when incorporated on a non-articulated airfoil, but when you incorporate an articulated trailing edge (elevator), then the asymmetric force becomes torque on the torque tube and stick deflection instead of into a forward pitching component applied to the rigid wing structure. By countering this effect with the sparrow strainer you actually loose some of the positive characteristics of the pitching moment, and you add a lot of drag. If you could manage it as a pilot, and this is not recommended, the LS-1 would fly better and be more efficient if you could hold the elevator neutral with the stick. But this would require always be pulling lots of aft stick-force. The stick force would be very large in full cruise, and you would never find a hands off condition. It gives you an appreciation for the force that the sparrow strainer supports are experiencing constantly in flight, and why one might potentially depart the aircraft….requiring above average flying skills to recover. I have modeled the forces on the LS-1 elevator and have also designed a modified LS-1 airfoil with the rear portion of the camber removed, where the forces on the redesigned elevator are balanced, (so the sparrow strainer would not be required). I have thought that sometime I would like to build a new set of these redesigned elevators and put them on my plane, but I am just getting comfortable flying with the plans design. On the redesigned airfoil, the lift profile and polars are essentially identical to the LS-1, but what is the big unknown is how the redesigned elevator would impact that stall behavior. Small changes at the trailing edge can be quite impactful on stall, and my modeling method cannot model the complexity of airflow at stall. Cheers, Jay From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Bruce Crain
Sent: Sunday, December 15, 2019 9:32 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil Not sure I really care to know. Either way I will still be aviating in both and won't put any more sound insulation in either one. (more weight) On a side note I have been doing some tuft testing which might be more informational. I have found out that if I pull up the nose and then unload it by pushing forward on the stick my sparrow strainers are stalling on the bottom side. My TriQ will not recover in most instances until I stall out or slow down the airspeed a bunch so that I can pull the stick enough for the strainers to reattach the air underneath them. I just received some vortex generators to put on the bottom of the strainers to do more testing and will hopefully have them in place this week to test. I have noticed in the past that when I do an aileron roll this happens. I have been all though the elevators and ailerons to make sure they were tight and they now are very solid. So then I thought that maybe the wingtip vortices were coming up from the canard and rolling down on the main wing. That never really looked like a good theory. So I installed yarn tufts to see just what was going on. When I flew it started to dawn on me that the elevator was coming up every time I experienced the phenomenon. So I had a good idea that something much simpler was happening and it kept pointing to the sparrow strainer. After talking with Paul Fisher, Jerry Marstall, Sammy Hoskins, and even Scott Swing at Velocity I decided we were looking at a stall. Sure enough when I went up with the tufts in place on the canard and the top and bottom of the sparrow strainers I thought "what if I just pull up and then push forward on the stick could I replicate the problem". When I pulled up and then unloaded the canard by pushing over the sparrow strainers held for a bit and then they relaxed to stick forward an inch or so. I looked out and saw the elevators up about and inch or so and videoed the tufts on the bottom of the strainer disappear and the tufts on the top tufts wrap around the back of the strainer and disappear forward under the strainer! I spoke with Paul, Jerry and Scott again and Scott was freaked but agreed that was what is happening. Bingo! Now I have to fix it so that is where the vortex generator come in. The strainers are a really sensitive trim from dealing with them in the past plus I have them mounted half way outboard on the elevator. I also have 1.2 degrees incidence up on the canard and .8 degrees up on the main wing so we are talking apples to oranges. Sure I could just fly the Q and not go negative on the elevator enough to stall them but I like to do aileron rolls when I am board. I believe you and I experienced the stall when you were getting time in my Q before your first flight. So we educate and experiment and come out improving the species.
---------- Original Message ----------
From: "Jay Scheevel" <jay@...>
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 19:53:06 -0700 If you have an iPhone it has an app available that measures abient noise level. You could give that a try. Sent from my Verizon Wireless 4G LTE DROID
Bruce Crain <jcrain2@...> wrote:
I have not noticed which one is quieter. Will try to do that in the future. Trouble is remembering how loud the other plane is between switches. I will tell Charlie hello for you Dr Mike! Bruce
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001@...>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Mon, 16 Dec 2019 01:37:25 +0000 (UTC)
Hi Mike, My RV6A is noisy. I have a Clark headset modified for active noise reduction but my new Zulu 3 is quieter. I have a Lycoming O-320 E2D 150 with a metal Sensinich prop. I have problem believing a Quickie 200 is quieter. Mike On Sun, Dec 15, 2019 at 7:33 PM, Mike Dwyer I flew in a RV4 recently and I think the inside cockpit of the RV is a lot noisier than a Q200. I'd expect the fiberglass sandwich to dampen some noise. On Sun, Dec 15, 2019 at 8:14 PM Bruce Crain <jcrain2@...> wrote: Sweet! Hope you design a mach .5 airfoil for the Quickie guys Wouldn't that be sweet! I still have my TriQ 200 but I went over to the "Dark Side" when my hanger mate Charlie Calivas sold me his RV 6 for a song and a dance and then proceeded to help me rebuild the engine! My son Jake calls me "2 planes Crain"!
Have a Merry Christmas! Bruce and Honeylamb Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 04:06:52 +0000 (UTC)
Bruce! Good to hear from you as well. Things are great in Wichita. I'm still designing GA airfoils and flying my RV6A and Cessna 120. I went through Emporia two weeks ago and it reminded me of when you, your son, and I got weathered in coming back from the Quickie fly-in at Ottawa. Great hearing from you! My thanks to the Q-List group for letting me "announce" our moving Shuck Airfoil from Yahoo! Groups to Groups.io ! On Sat, Dec 14, 2019 at 9:44 PM, Bruce Crain Good to hear from you again Dr Shuck! How are things in Wichita? Bruce Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 00:24:29 +0000 (UTC) Just to let you know I am in process of moving the former Yahoo! Groups Shuck Airfoil to: I was late getting the mailing list moved over so I would be very thankful if you would post this as many of the Shuck Airfoil group at Yahoo! Groups also were members of Q-List. Moderator of the former Yahoo! Groups Shuck Airfoil
|
|
|
Jay, John Roncz came up with the solution to this many years ago. It’s called the “Roncz canard” in the Long-EZ community. It’s an excellent airfoil, but particularly important is what he did to the elevator. The same technique could be used on the LS-1 elevator to mitigate the elevator hinge moment. It can be modeled fairly accurately in X-foil or in Roncz’s modified Eppler airfoil code that he used back then (freely available on the internet). Just gotta tweak it so the elevator floating angle is stable and appropriate for the airplane’s approximate maximum range low cruise airspeed so that if the trim and elevator control systems accidentally disconnect in flight the airplane will be able to continue flight and land using engine power modulation (and reflex if installed) as primary pitch control. Rutan laid out all these requirements in one of the Canard Pusher newsletters in the 1980s. David J. Gall
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Jay Scheevel Sent: Monday, December 16, 2019 8:10 AM To: main@Q-List.groups.io Subject: [Q-List] Bruce's tuft study on sparrow strainers Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do. Seriously, That is an interesting observation. Ideally, you would like your “trim” surfaces, such as the sparrow strainer to be well behaved under all flight conditions, but you have demonstrated that this is not the case. The sparrow strainer flies at a high AOA (negative) all the time, so as to apply a large load to the trailing edge of the elevator, push it into an accelerated condition and boom, you get it to stall. The need for them is entirely the because the aft-1/3 of the LS-1 airfoil has a significant camber on the underside. This camber is by design yielding favorable characteristics when incorporated on a non-articulated airfoil, but when you incorporate an articulated trailing edge (elevator), then the asymmetric force becomes torque on the torque tube and stick deflection instead of into a forward pitching component applied to the rigid wing structure. By countering this effect with the sparrow strainer you actually loose some of the positive characteristics of the pitching moment, and you add a lot of drag. If you could manage it as a pilot, and this is not recommended, the LS-1 would fly better and be more efficient if you could hold the elevator neutral with the stick. But this would require always be pulling lots of aft stick-force. The stick force would be very large in full cruise, and you would never find a hands off condition. It gives you an appreciation for the force that the sparrow strainer supports are experiencing constantly in flight, and why one might potentially depart the aircraft….requiring above average flying skills to recover. I have modeled the forces on the LS-1 elevator and have also designed a modified LS-1 airfoil with the rear portion of the camber removed, where the forces on the redesigned elevator are balanced, (so the sparrow strainer would not be required). I have thought that sometime I would like to build a new set of these redesigned elevators and put them on my plane, but I am just getting comfortable flying with the plans design. On the redesigned airfoil, the lift profile and polars are essentially identical to the LS-1, but what is the big unknown is how the redesigned elevator would impact that stall behavior. Small changes at the trailing edge can be quite impactful on stall, and my modeling method cannot model the complexity of airflow at stall. Cheers, Jay From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Bruce Crain
Sent: Sunday, December 15, 2019 9:32 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil Not sure I really care to know. Either way I will still be aviating in both and won't put any more sound insulation in either one. (more weight) On a side note I have been doing some tuft testing which might be more informational. I have found out that if I pull up the nose and then unload it by pushing forward on the stick my sparrow strainers are stalling on the bottom side. My TriQ will not recover in most instances until I stall out or slow down the airspeed a bunch so that I can pull the stick enough for the strainers to reattach the air underneath them. I just received some vortex generators to put on the bottom of the strainers to do more testing and will hopefully have them in place this week to test. I have noticed in the past that when I do an aileron roll this happens. I have been all though the elevators and ailerons to make sure they were tight and they now are very solid. So then I thought that maybe the wingtip vortices were coming up from the canard and rolling down on the main wing. That never really looked like a good theory. So I installed yarn tufts to see just what was going on. When I flew it started to dawn on me that the elevator was coming up every time I experienced the phenomenon. So I had a good idea that something much simpler was happening and it kept pointing to the sparrow strainer. After talking with Paul Fisher, Jerry Marstall, Sammy Hoskins, and even Scott Swing at Velocity I decided we were looking at a stall. Sure enough when I went up with the tufts in place on the canard and the top and bottom of the sparrow strainers I thought "what if I just pull up and then push forward on the stick could I replicate the problem". When I pulled up and then unloaded the canard by pushing over the sparrow strainers held for a bit and then they relaxed to stick forward an inch or so. I looked out and saw the elevators up about and inch or so and videoed the tufts on the bottom of the strainer disappear and the tufts on the top tufts wrap around the back of the strainer and disappear forward under the strainer! I spoke with Paul, Jerry and Scott again and Scott was freaked but agreed that was what is happening. Bingo! Now I have to fix it so that is where the vortex generator come in. The strainers are a really sensitive trim from dealing with them in the past plus I have them mounted half way outboard on the elevator. I also have 1.2 degrees incidence up on the canard and .8 degrees up on the main wing so we are talking apples to oranges. Sure I could just fly the Q and not go negative on the elevator enough to stall them but I like to do aileron rolls when I am board. I believe you and I experienced the stall when you were getting time in my Q before your first flight. So we educate and experiment and come out improving the species.
---------- Original Message ----------
From: "Jay Scheevel" <jay@...>
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 19:53:06 -0700 If you have an iPhone it has an app available that measures abient noise level. You could give that a try. Sent from my Verizon Wireless 4G LTE DROID
Bruce Crain <jcrain2@...> wrote:
I have not noticed which one is quieter. Will try to do that in the future. Trouble is remembering how loud the other plane is between switches. I will tell Charlie hello for you Dr Mike! Bruce
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001@...>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Mon, 16 Dec 2019 01:37:25 +0000 (UTC)
Hi Mike, My RV6A is noisy. I have a Clark headset modified for active noise reduction but my new Zulu 3 is quieter. I have a Lycoming O-320 E2D 150 with a metal Sensinich prop. I have problem believing a Quickie 200 is quieter. Mike On Sun, Dec 15, 2019 at 7:33 PM, Mike Dwyer I flew in a RV4 recently and I think the inside cockpit of the RV is a lot noisier than a Q200. I'd expect the fiberglass sandwich to dampen some noise. On Sun, Dec 15, 2019 at 8:14 PM Bruce Crain <jcrain2@...> wrote: Sweet! Hope you design a mach .5 airfoil for the Quickie guys Wouldn't that be sweet! I still have my TriQ 200 but I went over to the "Dark Side" when my hanger mate Charlie Calivas sold me his RV 6 for a song and a dance and then proceeded to help me rebuild the engine! My son Jake calls me "2 planes Crain"!
Have a Merry Christmas! Bruce and Honeylamb Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 04:06:52 +0000 (UTC)
Bruce! Good to hear from you as well. Things are great in Wichita. I'm still designing GA airfoils and flying my RV6A and Cessna 120. I went through Emporia two weeks ago and it reminded me of when you, your son, and I got weathered in coming back from the Quickie fly-in at Ottawa. Great hearing from you! My thanks to the Q-List group for letting me "announce" our moving Shuck Airfoil from Yahoo! Groups to Groups.io ! On Sat, Dec 14, 2019 at 9:44 PM, Bruce Crain Good to hear from you again Dr Shuck! How are things in Wichita? Bruce Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 00:24:29 +0000 (UTC) Just to let you know I am in process of moving the former Yahoo! Groups Shuck Airfoil to: I was late getting the mailing list moved over so I would be very thankful if you would post this as many of the Shuck Airfoil group at Yahoo! Groups also were members of Q-List. Moderator of the former Yahoo! Groups Shuck Airfoil
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Jay Scheevel
Follow the plans for construction of the sparrow strainers (meaning plywood support arm cores per plans, then reinforced with glass/epoxy lapped onto the elevator per plans). I added an extra ply of unidirectional glass with uni parallel to the supports, wrapped in another layer of bidirectional glass on the support arms, also lapping onto the elevator. My extra layers are in addition to what is called for in the plans. Your sign off seems to indicate you have a dragonfly. The dragonfly has a GU canard, so the sparrow strainers undergo lower loads than they do on the LS-1. I suspect the plans indicate that they are more lightly built. The Q-2 with the GU canard did not have sparrow strainers. I am sure Charlie can comment more fully on DF related issues. Jay N8WQ
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Jeffrey Bevilacqua via Groups.Io Sent: Monday, December 16, 2019 10:23 AM To: main@Q-List.groups.io Subject: Re: [Q-List] Bruce's tuft study on sparrow strainers Justa quick question. Can anyone recommend a reliable adhesive to attach the Sparrow Strainers to the elevator considering the constant high loads. Thanks. On Monday, December 16, 2019, 09:15:41 AM PST, One Sky Dog via Groups.Io <oneskydog@...> wrote: Bruce roll the RV problem solved. I know Tex Johnson rolled a 707 so why not a Q? Milk stool pilot
On Dec 16, 2019, at 9:09 AM, Jay Scheevel <jay@...> wrote:
Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do. Seriously, That is an interesting observation. Ideally, you would like your “trim” surfaces, such as the sparrow strainer to be well behaved under all flight conditions, but you have demonstrated that this is not the case. The sparrow strainer flies at a high AOA (negative) all the time, so as to apply a large load to the trailing edge of the elevator, push it into an accelerated condition and boom, you get it to stall. The need for them is entirely the because the aft-1/3 of the LS-1 airfoil has a significant camber on the underside. This camber is by design yielding favorable characteristics when incorporated on a non-articulated airfoil, but when you incorporate an articulated trailing edge (elevator), then the asymmetric force becomes torque on the torque tube and stick deflection instead of into a forward pitching component applied to the rigid wing structure. By countering this effect with the sparrow strainer you actually loose some of the positive characteristics of the pitching moment, and you add a lot of drag. If you could manage it as a pilot, and this is not recommended, the LS-1 would fly better and be more efficient if you could hold the elevator neutral with the stick. But this would require always be pulling lots of aft stick-force. The stick force would be very large in full cruise, and you would never find a hands off condition. It gives you an appreciation for the force that the sparrow strainer supports are experiencing constantly in flight, and why one might potentially depart the aircraft….requiring above average flying skills to recover. I have modeled the forces on the LS-1 elevator and have also designed a modified LS-1 airfoil with the rear portion of the camber removed, where the forces on the redesigned elevator are balanced, (so the sparrow strainer would not be required). I have thought that sometime I would like to build a new set of these redesigned elevators and put them on my plane, but I am just getting comfortable flying with the plans design. On the redesigned airfoil, the lift profile and polars are essentially identical to the LS-1, but what is the big unknown is how the redesigned elevator would impact that stall behavior. Small changes at the trailing edge can be quite impactful on stall, and my modeling method cannot model the complexity of airflow at stall. Cheers, Jay From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Bruce Crain
Sent: Sunday, December 15, 2019 9:32 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil Not sure I really care to know. Either way I will still be aviating in both and won't put any more sound insulation in either one. (more weight) On a side note I have been doing some tuft testing which might be more informational. I have found out that if I pull up the nose and then unload it by pushing forward on the stick my sparrow strainers are stalling on the bottom side. My TriQ will not recover in most instances until I stall out or slow down the airspeed a bunch so that I can pull the stick enough for the strainers to reattach the air underneath them. I just received some vortex generators to put on the bottom of the strainers to do more testing and will hopefully have them in place this week to test. I have noticed in the past that when I do an aileron roll this happens. I have been all though the elevators and ailerons to make sure they were tight and they now are very solid. So then I thought that maybe the wingtip vortices were coming up from the canard and rolling down on the main wing. That never really looked like a good theory. So I installed yarn tufts to see just what was going on. When I flew it started to dawn on me that the elevator was coming up every time I experienced the phenomenon. So I had a good idea that something much simpler was happening and it kept pointing to the sparrow strainer. After talking with Paul Fisher, Jerry Marstall, Sammy Hoskins, and even Scott Swing at Velocity I decided we were looking at a stall. Sure enough when I went up with the tufts in place on the canard and the top and bottom of the sparrow strainers I thought "what if I just pull up and then push forward on the stick could I replicate the problem". When I pulled up and then unloaded the canard by pushing over the sparrow strainers held for a bit and then they relaxed to stick forward an inch or so. I looked out and saw the elevators up about and inch or so and videoed the tufts on the bottom of the strainer disappear and the tufts on the top tufts wrap around the back of the strainer and disappear forward under the strainer! I spoke with Paul, Jerry and Scott again and Scott was freaked but agreed that was what is happening. Bingo! Now I have to fix it so that is where the vortex generator come in. The strainers are a really sensitive trim from dealing with them in the past plus I have them mounted half way outboard on the elevator. I also have 1.2 degrees incidence up on the canard and .8 degrees up on the main wing so we are talking apples to oranges. Sure I could just fly the Q and not go negative on the elevator enough to stall them but I like to do aileron rolls when I am board. I believe you and I experienced the stall when you were getting time in my Q before your first flight. So we educate and experiment and come out improving the species.
---------- Original Message ----------
From: "Jay Scheevel" <jay@...>
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 19:53:06 -0700 If you have an iPhone it has an app available that measures abient noise level. You could give that a try. Sent from my Verizon Wireless 4G LTE DROID
Bruce Crain <jcrain2@...> wrote:
I have not noticed which one is quieter. Will try to do that in the future. Trouble is remembering how loud the other plane is between switches. I will tell Charlie hello for you Dr Mike! Bruce
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001@...>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Mon, 16 Dec 2019 01:37:25 +0000 (UTC)
Hi Mike, My RV6A is noisy. I have a Clark headset modified for active noise reduction but my new Zulu 3 is quieter. I have a Lycoming O-320 E2D 150 with a metal Sensinich prop. I have problem believing a Quickie 200 is quieter. Mike On Sun, Dec 15, 2019 at 7:33 PM, Mike Dwyer I flew in a RV4 recently and I think the inside cockpit of the RV is a lot noisier than a Q200. I'd expect the fiberglass sandwich to dampen some noise. On Sun, Dec 15, 2019 at 8:14 PM Bruce Crain <jcrain2@...> wrote: Sweet! Hope you design a mach .5 airfoil for the Quickie guys Wouldn't that be sweet! I still have my TriQ 200 but I went over to the "Dark Side" when my hanger mate Charlie Calivas sold me his RV 6 for a song and a dance and then proceeded to help me rebuild the engine! My son Jake calls me "2 planes Crain"!
Have a Merry Christmas! Bruce and Honeylamb Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 04:06:52 +0000 (UTC)
Bruce! Good to hear from you as well. Things are great in Wichita. I'm still designing GA airfoils and flying my RV6A and Cessna 120. I went through Emporia two weeks ago and it reminded me of when you, your son, and I got weathered in coming back from the Quickie fly-in at Ottawa. Great hearing from you! My thanks to the Q-List group for letting me "announce" our moving Shuck Airfoil from Yahoo! Groups to Groups.io ! On Sat, Dec 14, 2019 at 9:44 PM, Bruce Crain Good to hear from you again Dr Shuck! How are things in Wichita? Bruce Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 00:24:29 +0000 (UTC) Just to let you know I am in process of moving the former Yahoo! Groups Shuck Airfoil to: I was late getting the mailing list moved over so I would be very thankful if you would post this as many of the Shuck Airfoil group at Yahoo! Groups also were members of Q-List. Moderator of the former Yahoo! Groups Shuck Airfoil
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Bruce Crain
Yes. Radius the arms that mount to the elevator so that the BID attaches to them without sharp angles. Then scuff up the elevator where they attach at least 1" on both sides of the arms. Be sure you are not epoxying the arms and BID to paint plus do not cut to far down into the glass surfaces on the elevator. The glass there is not very thick on the elevator.
Put some flox in the inside angles of the arms so the BID radius isn't to sharp. Clear as mud?!
Bruce
---------- Original Message ---------- From: "Jeffrey Bevilacqua via Groups.Io" <jlbevila@...> To: <main@Q-List.groups.io> Subject: Re: [Q-List] Bruce's tuft study on sparrow strainers Date: Mon, 16 Dec 2019 17:23:27 +0000 (UTC)
Justa quick question. Can anyone recommend a reliable adhesive to attach the Sparrow Strainers to the elevator considering the constant high loads. Thanks.
Jeff Bevilacqua DF MK H.
On Monday, December 16, 2019, 09:15:41 AM PST, One Sky Dog via Groups.Io <oneskydog@...> wrote:
Bruce roll the RV problem solved.
I know Tex Johnson rolled a 707 so why not a Q?
Milk stool pilot
On Dec 16, 2019, at 9:09 AM, Jay Scheevel < jay@...> wrote:
Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do.
Seriously, That is an interesting observation. Ideally, you would like your “trim” surfaces, such as the sparrow strainer to be well behaved under all flight conditions, but you have demonstrated that this is not the case. The sparrow strainer flies at a high AOA (negative) all the time, so as to apply a large load to the trailing edge of the elevator, push it into an accelerated condition and boom, you get it to stall. The need for them is entirely the because the aft-1/3 of the LS-1 airfoil has a significant camber on the underside. This camber is by design yielding favorable characteristics when incorporated on a non-articulated airfoil, but when you incorporate an articulated trailing edge (elevator), then the asymmetric force becomes torque on the torque tube and stick deflection instead of into a forward pitching component applied to the rigid wing structure. By countering this effect with the sparrow strainer you actually loose some of the positive characteristics of the pitching moment, and you add a lot of drag. If you could manage it as a pilot, and this is not recommended, the LS-1 would fly better and be more efficient if you could hold the elevator neutral with the stick. But this would require always be pulling lots of aft stick-force. The stick force would be very large in full cruise, and you would never find a hands off condition. It gives you an appreciation for the force that the sparrow strainer supports are experiencing constantly in flight, and why one might potentially depart the aircraft….requiring above average flying skills to recover.
I have modeled the forces on the LS-1 elevator and have also designed a modified LS-1 airfoil with the rear portion of the camber removed, where the forces on the redesigned elevator are balanced, (so the sparrow strainer would not be required). I have thought that sometime I would like to build a new set of these redesigned elevators and put them on my plane, but I am just getting comfortable flying with the plans design. On the redesigned airfoil, the lift profile and polars are essentially identical to the LS-1, but what is the big unknown is how the redesigned elevator would impact that stall behavior. Small changes at the trailing edge can be quite impactful on stall, and my modeling method cannot model the complexity of airflow at stall.
Cheers,
Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Bruce Crain
Sent: Sunday, December 15, 2019 9:32 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Not sure I really care to know. Either way I will still be aviating in both and won't put any more sound insulation in either one. (more weight)
On a side note I have been doing some tuft testing which might be more informational. I have found out that if I pull up the nose and then unload it by pushing forward on the stick my sparrow strainers are stalling on the bottom side. My TriQ will not recover in most instances until I stall out or slow down the airspeed a bunch so that I can pull the stick enough for the strainers to reattach the air underneath them. I just received some vortex generators to put on the bottom of the strainers to do more testing and will hopefully have them in place this week to test.
I have noticed in the past that when I do an aileron roll this happens. I have been all though the elevators and ailerons to make sure they were tight and they now are very solid. So then I thought that maybe the wingtip vortices were coming up from the canard and rolling down on the main wing. That never really looked like a good theory. So I installed yarn tufts to see just what was going on. When I flew it started to dawn on me that the elevator was coming up every time I experienced the phenomenon. So I had a good idea that something much simpler was happening and it kept pointing to the sparrow strainer. After talking with Paul Fisher, Jerry Marstall, Sammy Hoskins, and even Scott Swing at Velocity I decided we were looking at a stall. Sure enough when I went up with the tufts in place on the canard and the top and bottom of the sparrow strainers I thought "what if I just pull up and then push forward on the stick could I replicate the problem". When I pulled up and then unloaded the canard by pushing over the sparrow strainers held for a bit and then they relaxed to stick forward an inch or so. I looked out and saw the elevators up about and inch or so and videoed the tufts on the bottom of the strainer disappear and the tufts on the top tufts wrap around the back of the strainer and disappear forward under the strainer! I spoke with Paul, Jerry and Scott again and Scott was freaked but agreed that was what is happening.
Bingo! Now I have to fix it so that is where the vortex generator come in. The strainers are a really sensitive trim from dealing with them in the past plus I have them mounted half way outboard on the elevator. I also have 1.2 degrees incidence up on the canard and .8 degrees up on the main wing so we are talking apples to oranges.
Sure I could just fly the Q and not go negative on the elevator enough to stall them but I like to do aileron rolls when I am board. I believe you and I experienced the stall when you were getting time in my Q before your first flight. So we educate and experiment and come out improving the species.
---------- Original Message ----------
From: "Jay Scheevel" <jay@...>
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 19:53:06 -0700
If you have an iPhone it has an app available that measures abient noise level. You could give that a try.
Sent from my Verizon Wireless 4G LTE DROID
Bruce Crain <jcrain2@...> wrote:
I have not noticed which one is quieter. Will try to do that in the future. Trouble is remembering how loud the other plane is between switches.
I will tell Charlie hello for you Dr Mike!
Bruce
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001@...>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Mon, 16 Dec 2019 01:37:25 +0000 (UTC)
Hi Mike,
My RV6A is noisy. I have a Clark headset modified for active noise reduction but my new Zulu 3 is quieter. I have a Lycoming O-320 E2D 150 with a metal Sensinich prop. I have problem believing a Quickie 200 is quieter.
Mike
On Sun, Dec 15, 2019 at 7:33 PM, Mike Dwyer
I flew in a RV4 recently and I think the inside cockpit of the RV is a lot noisier than a Q200. I'd expect the fiberglass sandwich to dampen some noise.
On Sun, Dec 15, 2019 at 8:14 PM Bruce Crain <jcrain2@...> wrote:
Sweet! Hope you design a mach .5 airfoil for the Quickie guys Wouldn't that be sweet!
I still have my TriQ 200 but I went over to the "Dark Side" when my hanger mate Charlie Calivas sold me his RV 6 for a song and a dance and then proceeded to help me rebuild the engine! My son Jake calls me "2 planes Crain"!
Have a Merry Christmas!
Bruce and Honeylamb Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 04:06:52 +0000 (UTC)
Bruce!
Good to hear from you as well. Things are great in Wichita. I'm still designing GA airfoils and flying my RV6A and Cessna 120. I went through Emporia two weeks ago and it reminded me of when you, your son, and I got weathered in coming back from the Quickie fly-in at Ottawa.
Great hearing from you! My thanks to the Q-List group for letting me "announce" our moving Shuck Airfoil from Yahoo! Groups to Groups.io !
On Sat, Dec 14, 2019 at 9:44 PM, Bruce Crain
Good to hear from you again Dr Shuck! How are things in Wichita?
Bruce Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 00:24:29 +0000 (UTC)
Just to let you know I am in process of moving the former Yahoo! Groups Shuck Airfoil to:
I was late getting the mailing list moved over so I would be very thankful if you would post this as many
of the Shuck Airfoil group at Yahoo! Groups also were members of Q-List.
Moderator of the former Yahoo! Groups Shuck Airfoil
|
|
|
Bruce Crain
 You are right Charlie! Put that on the "placard" for things not to do! And never with Honey Lamb in the right seat! B
Bruce roll the RV problem solved.
I know Tex Johnson rolled a 707 so why not a Q?
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|
|
Jeffrey Bevilacqua <jlbevila@...>
Justa quick question. Can anyone recommend a reliable adhesive to attach the Sparrow Strainers to the elevator considering the constant high loads. Thanks. Jeff Bevilacqua DF MK H.
On Monday, December 16, 2019, 09:15:41 AM PST, One Sky Dog via Groups.Io <oneskydog@...> wrote:
Bruce roll the RV problem solved.
I know Tex Johnson rolled a 707 so why not a Q?
Milk stool pilot On Dec 16, 2019, at 9:09 AM, Jay Scheevel < jay@...> wrote:
Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do. Seriously, That is an interesting observation. Ideally, you would like your “trim” surfaces, such as the sparrow strainer to be well behaved under all flight conditions, but you have demonstrated that this is not the case. The sparrow strainer flies at a high AOA (negative) all the time, so as to apply a large load to the trailing edge of the elevator, push it into an accelerated condition and boom, you get it to stall. The need for them is entirely the because the aft-1/3 of the LS-1 airfoil has a significant camber on the underside. This camber is by design yielding favorable characteristics when incorporated on a non-articulated airfoil, but when you incorporate an articulated trailing edge (elevator), then the asymmetric force becomes torque on the torque tube and stick deflection instead of into a forward pitching component applied to the rigid wing structure. By countering this effect with the sparrow strainer you actually loose some of the positive characteristics of the pitching moment, and you add a lot of drag. If you could manage it as a pilot, and this is not recommended, the LS-1 would fly better and be more efficient if you could hold the elevator neutral with the stick. But this would require always be pulling lots of aft stick-force. The stick force would be very large in full cruise, and you would never find a hands off condition. It gives you an appreciation for the force that the sparrow strainer supports are experiencing constantly in flight, and why one might potentially depart the aircraft….requiring above average flying skills to recover. I have modeled the forces on the LS-1 elevator and have also designed a modified LS-1 airfoil with the rear portion of the camber removed, where the forces on the redesigned elevator are balanced, (so the sparrow strainer would not be required). I have thought that sometime I would like to build a new set of these redesigned elevators and put them on my plane, but I am just getting comfortable flying with the plans design. On the redesigned airfoil, the lift profile and polars are essentially identical to the LS-1, but what is the big unknown is how the redesigned elevator would impact that stall behavior. Small changes at the trailing edge can be quite impactful on stall, and my modeling method cannot model the complexity of airflow at stall. Cheers, Jay From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Bruce Crain
Sent: Sunday, December 15, 2019 9:32 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil Not sure I really care to know. Either way I will still be aviating in both and won't put any more sound insulation in either one. (more weight) On a side note I have been doing some tuft testing which might be more informational. I have found out that if I pull up the nose and then unload it by pushing forward on the stick my sparrow strainers are stalling on the bottom side. My TriQ will not recover in most instances until I stall out or slow down the airspeed a bunch so that I can pull the stick enough for the strainers to reattach the air underneath them. I just received some vortex generators to put on the bottom of the strainers to do more testing and will hopefully have them in place this week to test. I have noticed in the past that when I do an aileron roll this happens. I have been all though the elevators and ailerons to make sure they were tight and they now are very solid. So then I thought that maybe the wingtip vortices were coming up from the canard and rolling down on the main wing. That never really looked like a good theory. So I installed yarn tufts to see just what was going on. When I flew it started to dawn on me that the elevator was coming up every time I experienced the phenomenon. So I had a good idea that something much simpler was happening and it kept pointing to the sparrow strainer. After talking with Paul Fisher, Jerry Marstall, Sammy Hoskins, and even Scott Swing at Velocity I decided we were looking at a stall. Sure enough when I went up with the tufts in place on the canard and the top and bottom of the sparrow strainers I thought "what if I just pull up and then push forward on the stick could I replicate the problem". When I pulled up and then unloaded the canard by pushing over the sparrow strainers held for a bit and then they relaxed to stick forward an inch or so. I looked out and saw the elevators up about and inch or so and videoed the tufts on the bottom of the strainer disappear and the tufts on the top tufts wrap around the back of the strainer and disappear forward under the strainer! I spoke with Paul, Jerry and Scott again and Scott was freaked but agreed that was what is happening. Bingo! Now I have to fix it so that is where the vortex generator come in. The strainers are a really sensitive trim from dealing with them in the past plus I have them mounted half way outboard on the elevator. I also have 1.2 degrees incidence up on the canard and .8 degrees up on the main wing so we are talking apples to oranges. Sure I could just fly the Q and not go negative on the elevator enough to stall them but I like to do aileron rolls when I am board. I believe you and I experienced the stall when you were getting time in my Q before your first flight. So we educate and experiment and come out improving the species.
---------- Original Message ----------
From: "Jay Scheevel" <jay@...>
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 19:53:06 -0700 If you have an iPhone it has an app available that measures abient noise level. You could give that a try. Sent from my Verizon Wireless 4G LTE DROID
Bruce Crain <jcrain2@...> wrote:
I have not noticed which one is quieter. Will try to do that in the future. Trouble is remembering how loud the other plane is between switches. I will tell Charlie hello for you Dr Mike! Bruce
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001@...>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Mon, 16 Dec 2019 01:37:25 +0000 (UTC)
Hi Mike, My RV6A is noisy. I have a Clark headset modified for active noise reduction but my new Zulu 3 is quieter. I have a Lycoming O-320 E2D 150 with a metal Sensinich prop. I have problem believing a Quickie 200 is quieter. Mike On Sun, Dec 15, 2019 at 7:33 PM, Mike Dwyer I flew in a RV4 recently and I think the inside cockpit of the RV is a lot noisier than a Q200. I'd expect the fiberglass sandwich to dampen some noise. On Sun, Dec 15, 2019 at 8:14 PM Bruce Crain <jcrain2@...> wrote: Sweet! Hope you design a mach .5 airfoil for the Quickie guys Wouldn't that be sweet! I still have my TriQ 200 but I went over to the "Dark Side" when my hanger mate Charlie Calivas sold me his RV 6 for a song and a dance and then proceeded to help me rebuild the engine! My son Jake calls me "2 planes Crain"!
Have a Merry Christmas! Bruce and Honeylamb Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 04:06:52 +0000 (UTC)
Bruce! Good to hear from you as well. Things are great in Wichita. I'm still designing GA airfoils and flying my RV6A and Cessna 120. I went through Emporia two weeks ago and it reminded me of when you, your son, and I got weathered in coming back from the Quickie fly-in at Ottawa. Great hearing from you! My thanks to the Q-List group for letting me "announce" our moving Shuck Airfoil from Yahoo! Groups to Groups.io ! On Sat, Dec 14, 2019 at 9:44 PM, Bruce Crain Good to hear from you again Dr Shuck! How are things in Wichita? Bruce Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 00:24:29 +0000 (UTC) Just to let you know I am in process of moving the former Yahoo! Groups Shuck Airfoil to: I was late getting the mailing list moved over so I would be very thankful if you would post this as many of the Shuck Airfoil group at Yahoo! Groups also were members of Q-List. Moderator of the former Yahoo! Groups Shuck Airfoil
|
|
|
One Sky Dog
Bruce roll the RV problem solved.
I know Tex Johnson rolled a 707 so why not a Q?
On Dec 16, 2019, at 9:09 AM, Jay Scheevel < jay@...> wrote: Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do. Seriously, That is an interesting observation. Ideally, you would like your “trim” surfaces, such as the sparrow strainer to be well behaved under all flight conditions, but you have demonstrated that this is not the case. The sparrow strainer flies at a high AOA (negative) all the time, so as to apply a large load to the trailing edge of the elevator, push it into an accelerated condition and boom, you get it to stall. The need for them is entirely the because the aft-1/3 of the LS-1 airfoil has a significant camber on the underside. This camber is by design yielding favorable characteristics when incorporated on a non-articulated airfoil, but when you incorporate an articulated trailing edge (elevator), then the asymmetric force becomes torque on the torque tube and stick deflection instead of into a forward pitching component applied to the rigid wing structure. By countering this effect with the sparrow strainer you actually loose some of the positive characteristics of the pitching moment, and you add a lot of drag. If you could manage it as a pilot, and this is not recommended, the LS-1 would fly better and be more efficient if you could hold the elevator neutral with the stick. But this would require always be pulling lots of aft stick-force. The stick force would be very large in full cruise, and you would never find a hands off condition. It gives you an appreciation for the force that the sparrow strainer supports are experiencing constantly in flight, and why one might potentially depart the aircraft….requiring above average flying skills to recover. I have modeled the forces on the LS-1 elevator and have also designed a modified LS-1 airfoil with the rear portion of the camber removed, where the forces on the redesigned elevator are balanced, (so the sparrow strainer would not be required). I have thought that sometime I would like to build a new set of these redesigned elevators and put them on my plane, but I am just getting comfortable flying with the plans design. On the redesigned airfoil, the lift profile and polars are essentially identical to the LS-1, but what is the big unknown is how the redesigned elevator would impact that stall behavior. Small changes at the trailing edge can be quite impactful on stall, and my modeling method cannot model the complexity of airflow at stall. Cheers, Jay From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Bruce Crain
Sent: Sunday, December 15, 2019 9:32 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil Not sure I really care to know. Either way I will still be aviating in both and won't put any more sound insulation in either one. (more weight) On a side note I have been doing some tuft testing which might be more informational. I have found out that if I pull up the nose and then unload it by pushing forward on the stick my sparrow strainers are stalling on the bottom side. My TriQ will not recover in most instances until I stall out or slow down the airspeed a bunch so that I can pull the stick enough for the strainers to reattach the air underneath them. I just received some vortex generators to put on the bottom of the strainers to do more testing and will hopefully have them in place this week to test. I have noticed in the past that when I do an aileron roll this happens. I have been all though the elevators and ailerons to make sure they were tight and they now are very solid. So then I thought that maybe the wingtip vortices were coming up from the canard and rolling down on the main wing. That never really looked like a good theory. So I installed yarn tufts to see just what was going on. When I flew it started to dawn on me that the elevator was coming up every time I experienced the phenomenon. So I had a good idea that something much simpler was happening and it kept pointing to the sparrow strainer. After talking with Paul Fisher, Jerry Marstall, Sammy Hoskins, and even Scott Swing at Velocity I decided we were looking at a stall. Sure enough when I went up with the tufts in place on the canard and the top and bottom of the sparrow strainers I thought "what if I just pull up and then push forward on the stick could I replicate the problem". When I pulled up and then unloaded the canard by pushing over the sparrow strainers held for a bit and then they relaxed to stick forward an inch or so. I looked out and saw the elevators up about and inch or so and videoed the tufts on the bottom of the strainer disappear and the tufts on the top tufts wrap around the back of the strainer and disappear forward under the strainer! I spoke with Paul, Jerry and Scott again and Scott was freaked but agreed that was what is happening. Bingo! Now I have to fix it so that is where the vortex generator come in. The strainers are a really sensitive trim from dealing with them in the past plus I have them mounted half way outboard on the elevator. I also have 1.2 degrees incidence up on the canard and .8 degrees up on the main wing so we are talking apples to oranges. Sure I could just fly the Q and not go negative on the elevator enough to stall them but I like to do aileron rolls when I am board. I believe you and I experienced the stall when you were getting time in my Q before your first flight. So we educate and experiment and come out improving the species.
---------- Original Message ----------
From: "Jay Scheevel" <jay@...>
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 19:53:06 -0700 If you have an iPhone it has an app available that measures abient noise level. You could give that a try. Sent from my Verizon Wireless 4G LTE DROID
Bruce Crain <jcrain2@...> wrote:
I have not noticed which one is quieter. Will try to do that in the future. Trouble is remembering how loud the other plane is between switches. I will tell Charlie hello for you Dr Mike! Bruce
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001@...>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Mon, 16 Dec 2019 01:37:25 +0000 (UTC)
Hi Mike, My RV6A is noisy. I have a Clark headset modified for active noise reduction but my new Zulu 3 is quieter. I have a Lycoming O-320 E2D 150 with a metal Sensinich prop. I have problem believing a Quickie 200 is quieter. Mike On Sun, Dec 15, 2019 at 7:33 PM, Mike Dwyer I flew in a RV4 recently and I think the inside cockpit of the RV is a lot noisier than a Q200. I'd expect the fiberglass sandwich to dampen some noise. On Sun, Dec 15, 2019 at 8:14 PM Bruce Crain <jcrain2@...> wrote: Sweet! Hope you design a mach .5 airfoil for the Quickie guys Wouldn't that be sweet! I still have my TriQ 200 but I went over to the "Dark Side" when my hanger mate Charlie Calivas sold me his RV 6 for a song and a dance and then proceeded to help me rebuild the engine! My son Jake calls me "2 planes Crain"!
Have a Merry Christmas! Bruce and Honeylamb Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 04:06:52 +0000 (UTC)
Bruce! Good to hear from you as well. Things are great in Wichita. I'm still designing GA airfoils and flying my RV6A and Cessna 120. I went through Emporia two weeks ago and it reminded me of when you, your son, and I got weathered in coming back from the Quickie fly-in at Ottawa. Great hearing from you! My thanks to the Q-List group for letting me "announce" our moving Shuck Airfoil from Yahoo! Groups to Groups.io ! On Sat, Dec 14, 2019 at 9:44 PM, Bruce Crain Good to hear from you again Dr Shuck! How are things in Wichita? Bruce Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 00:24:29 +0000 (UTC) Just to let you know I am in process of moving the former Yahoo! Groups Shuck Airfoil to: I was late getting the mailing list moved over so I would be very thankful if you would post this as many of the Shuck Airfoil group at Yahoo! Groups also were members of Q-List. Moderator of the former Yahoo! Groups Shuck Airfoil
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Bruce Crain
Jay and Michael,
You are both correct in saying be ready for changing flight conditions when changing the sparrow strainers. I have lots of experience with those changes when 1st setting up the strainers originally. On other occasions I have experienced changes in aircraft with different things going wrong or slipping or perhaps an electric trim quitting. Once when I flew through Eagle Nest Pass in bound for Angel Fire, NM I qued the mic only to find I had pushed the trim button on my RV. It started to tuk and I held pitch as best I could and then realized my error! With that said I wish to reiterate the saying
JUST FLY THE AIRCRAFT! Make it go where it is suppose to go! Forget everything else! Radios don't generate lift nor will they save your Popo!
I do have a video of the tufts changing direction but I used my iPhone and it is really shaky so maybe I can stop it and take a picture and send it to the Q-List.
Bruce Crain
---------- Original Message ---------- From: "Jay Scheevel" <jay@...> To: <main@Q-List.groups.io> Subject: [Q-List] Bruce's tuft study on sparrow strainers Date: Mon, 16 Dec 2019 09:09:58 -0700
Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do.
Seriously, That is an interesting observation. Ideally, you would like your “trim” surfaces, such as the sparrow strainer to be well behaved under all flight conditions, but you have demonstrated that this is not the case. The sparrow strainer flies at a high AOA (negative) all the time, so as to apply a large load to the trailing edge of the elevator, push it into an accelerated condition and boom, you get it to stall. The need for them is entirely the because the aft-1/3 of the LS-1 airfoil has a significant camber on the underside. This camber is by design yielding favorable characteristics when incorporated on a non-articulated airfoil, but when you incorporate an articulated trailing edge (elevator), then the asymmetric force becomes torque on the torque tube and stick deflection instead of into a forward pitching component applied to the rigid wing structure. By countering this effect with the sparrow strainer you actually loose some of the positive characteristics of the pitching moment, and you add a lot of drag. If you could manage it as a pilot, and this is not recommended, the LS-1 would fly better and be more efficient if you could hold the elevator neutral with the stick. But this would require always be pulling lots of aft stick-force. The stick force would be very large in full cruise, and you would never find a hands off condition. It gives you an appreciation for the force that the sparrow strainer supports are experiencing constantly in flight, and why one might potentially depart the aircraft….requiring above average flying skills to recover.
I have modeled the forces on the LS-1 elevator and have also designed a modified LS-1 airfoil with the rear portion of the camber removed, where the forces on the redesigned elevator are balanced, (so the sparrow strainer would not be required). I have thought that sometime I would like to build a new set of these redesigned elevators and put them on my plane, but I am just getting comfortable flying with the plans design. On the redesigned airfoil, the lift profile and polars are essentially identical to the LS-1, but what is the big unknown is how the redesigned elevator would impact that stall behavior. Small changes at the trailing edge can be quite impactful on stall, and my modeling method cannot model the complexity of airflow at stall.
Cheers,
Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Bruce Crain
Sent: Sunday, December 15, 2019 9:32 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Not sure I really care to know. Either way I will still be aviating in both and won't put any more sound insulation in either one. (more weight)
On a side note I have been doing some tuft testing which might be more informational. I have found out that if I pull up the nose and then unload it by pushing forward on the stick my sparrow strainers are stalling on the bottom side. My TriQ will not recover in most instances until I stall out or slow down the airspeed a bunch so that I can pull the stick enough for the strainers to reattach the air underneath them. I just received some vortex generators to put on the bottom of the strainers to do more testing and will hopefully have them in place this week to test.
I have noticed in the past that when I do an aileron roll this happens. I have been all though the elevators and ailerons to make sure they were tight and they now are very solid. So then I thought that maybe the wingtip vortices were coming up from the canard and rolling down on the main wing. That never really looked like a good theory. So I installed yarn tufts to see just what was going on. When I flew it started to dawn on me that the elevator was coming up every time I experienced the phenomenon. So I had a good idea that something much simpler was happening and it kept pointing to the sparrow strainer. After talking with Paul Fisher, Jerry Marstall, Sammy Hoskins, and even Scott Swing at Velocity I decided we were looking at a stall. Sure enough when I went up with the tufts in place on the canard and the top and bottom of the sparrow strainers I thought "what if I just pull up and then push forward on the stick could I replicate the problem". When I pulled up and then unloaded the canard by pushing over the sparrow strainers held for a bit and then they relaxed to stick forward an inch or so. I looked out and saw the elevators up about and inch or so and videoed the tufts on the bottom of the strainer disappear and the tufts on the top tufts wrap around the back of the strainer and disappear forward under the strainer! I spoke with Paul, Jerry and Scott again and Scott was freaked but agreed that was what is happening.
Bingo! Now I have to fix it so that is where the vortex generator come in. The strainers are a really sensitive trim from dealing with them in the past plus I have them mounted half way outboard on the elevator. I also have 1.2 degrees incidence up on the canard and .8 degrees up on the main wing so we are talking apples to oranges.
Sure I could just fly the Q and not go negative on the elevator enough to stall them but I like to do aileron rolls when I am board. I believe you and I experienced the stall when you were getting time in my Q before your first flight. So we educate and experiment and come out improving the species.
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Jay Scheevel
Thanks for the cool tuft study data, Bruce. My nerdiness must be rubbing off on you, or maybe you are just retired and want something time consuming to do. Seriously, That is an interesting observation. Ideally, you would like your “trim” surfaces, such as the sparrow strainer to be well behaved under all flight conditions, but you have demonstrated that this is not the case. The sparrow strainer flies at a high AOA (negative) all the time, so as to apply a large load to the trailing edge of the elevator, push it into an accelerated condition and boom, you get it to stall. The need for them is entirely the because the aft-1/3 of the LS-1 airfoil has a significant camber on the underside. This camber is by design yielding favorable characteristics when incorporated on a non-articulated airfoil, but when you incorporate an articulated trailing edge (elevator), then the asymmetric force becomes torque on the torque tube and stick deflection instead of into a forward pitching component applied to the rigid wing structure. By countering this effect with the sparrow strainer you actually loose some of the positive characteristics of the pitching moment, and you add a lot of drag. If you could manage it as a pilot, and this is not recommended, the LS-1 would fly better and be more efficient if you could hold the elevator neutral with the stick. But this would require always be pulling lots of aft stick-force. The stick force would be very large in full cruise, and you would never find a hands off condition. It gives you an appreciation for the force that the sparrow strainer supports are experiencing constantly in flight, and why one might potentially depart the aircraft….requiring above average flying skills to recover. I have modeled the forces on the LS-1 elevator and have also designed a modified LS-1 airfoil with the rear portion of the camber removed, where the forces on the redesigned elevator are balanced, (so the sparrow strainer would not be required). I have thought that sometime I would like to build a new set of these redesigned elevators and put them on my plane, but I am just getting comfortable flying with the plans design. On the redesigned airfoil, the lift profile and polars are essentially identical to the LS-1, but what is the big unknown is how the redesigned elevator would impact that stall behavior. Small changes at the trailing edge can be quite impactful on stall, and my modeling method cannot model the complexity of airflow at stall. Cheers, Jay
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Bruce Crain
Sent: Sunday, December 15, 2019 9:32 PM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil Not sure I really care to know. Either way I will still be aviating in both and won't put any more sound insulation in either one. (more weight) On a side note I have been doing some tuft testing which might be more informational. I have found out that if I pull up the nose and then unload it by pushing forward on the stick my sparrow strainers are stalling on the bottom side. My TriQ will not recover in most instances until I stall out or slow down the airspeed a bunch so that I can pull the stick enough for the strainers to reattach the air underneath them. I just received some vortex generators to put on the bottom of the strainers to do more testing and will hopefully have them in place this week to test. I have noticed in the past that when I do an aileron roll this happens. I have been all though the elevators and ailerons to make sure they were tight and they now are very solid. So then I thought that maybe the wingtip vortices were coming up from the canard and rolling down on the main wing. That never really looked like a good theory. So I installed yarn tufts to see just what was going on. When I flew it started to dawn on me that the elevator was coming up every time I experienced the phenomenon. So I had a good idea that something much simpler was happening and it kept pointing to the sparrow strainer. After talking with Paul Fisher, Jerry Marstall, Sammy Hoskins, and even Scott Swing at Velocity I decided we were looking at a stall. Sure enough when I went up with the tufts in place on the canard and the top and bottom of the sparrow strainers I thought "what if I just pull up and then push forward on the stick could I replicate the problem". When I pulled up and then unloaded the canard by pushing over the sparrow strainers held for a bit and then they relaxed to stick forward an inch or so. I looked out and saw the elevators up about and inch or so and videoed the tufts on the bottom of the strainer disappear and the tufts on the top tufts wrap around the back of the strainer and disappear forward under the strainer! I spoke with Paul, Jerry and Scott again and Scott was freaked but agreed that was what is happening. Bingo! Now I have to fix it so that is where the vortex generator come in. The strainers are a really sensitive trim from dealing with them in the past plus I have them mounted half way outboard on the elevator. I also have 1.2 degrees incidence up on the canard and .8 degrees up on the main wing so we are talking apples to oranges. Sure I could just fly the Q and not go negative on the elevator enough to stall them but I like to do aileron rolls when I am board. I believe you and I experienced the stall when you were getting time in my Q before your first flight. So we educate and experiment and come out improving the species.
---------- Original Message ----------
From: "Jay Scheevel" <jay@...>
To: main@Q-List.groups.io
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 19:53:06 -0700 If you have an iPhone it has an app available that measures abient noise level. You could give that a try. Sent from my Verizon Wireless 4G LTE DROID
Bruce Crain <jcrain2@...> wrote:
I have not noticed which one is quieter. Will try to do that in the future. Trouble is remembering how loud the other plane is between switches. I will tell Charlie hello for you Dr Mike! Bruce
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001@...>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Mon, 16 Dec 2019 01:37:25 +0000 (UTC)
Hi Mike, My RV6A is noisy. I have a Clark headset modified for active noise reduction but my new Zulu 3 is quieter. I have a Lycoming O-320 E2D 150 with a metal Sensinich prop. I have problem believing a Quickie 200 is quieter. Mike On Sun, Dec 15, 2019 at 7:33 PM, Mike Dwyer I flew in a RV4 recently and I think the inside cockpit of the RV is a lot noisier than a Q200. I'd expect the fiberglass sandwich to dampen some noise. On Sun, Dec 15, 2019 at 8:14 PM Bruce Crain <jcrain2@...> wrote: Sweet! Hope you design a mach .5 airfoil for the Quickie guys Wouldn't that be sweet! I still have my TriQ 200 but I went over to the "Dark Side" when my hanger mate Charlie Calivas sold me his RV 6 for a song and a dance and then proceeded to help me rebuild the engine! My son Jake calls me "2 planes Crain"!
Have a Merry Christmas! Bruce and Honeylamb Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: Re: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 04:06:52 +0000 (UTC)
Bruce! Good to hear from you as well. Things are great in Wichita. I'm still designing GA airfoils and flying my RV6A and Cessna 120. I went through Emporia two weeks ago and it reminded me of when you, your son, and I got weathered in coming back from the Quickie fly-in at Ottawa. Great hearing from you! My thanks to the Q-List group for letting me "announce" our moving Shuck Airfoil from Yahoo! Groups to Groups.io ! On Sat, Dec 14, 2019 at 9:44 PM, Bruce Crain Good to hear from you again Dr Shuck! How are things in Wichita? Bruce Crain
---------- Original Message ----------
From: "Mike Shuck via Groups.Io" <mikeshuck2001=yahoo.com@groups.io>
To: "main@Q-List.groups.io" <main@Q-List.groups.io>
Subject: [Q-List] Yahoo! Groups Shuck Airfoil
Date: Sun, 15 Dec 2019 00:24:29 +0000 (UTC) Just to let you know I am in process of moving the former Yahoo! Groups Shuck Airfoil to: I was late getting the mailing list moved over so I would be very thankful if you would post this as many of the Shuck Airfoil group at Yahoo! Groups also were members of Q-List. Moderator of the former Yahoo! Groups Shuck Airfoil
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