Elevator Trim Springy Thingy Really Needed?
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Humor me please, with a little bit of patience as I have only flown a Quickie once ... With a 2 axis autopilot and a reflexor, do I need the elevator trim spring setup at all?
I am asking for a few reasons ...
-- Robert "TheFrisco" Schmid (408) 805-5450 www.facebook.com/TheFlyingFriscos www.theflyingfriscos.com Love building planes almost as much as flying. Latest completed build is "Loki", a Chinook Plus 2 bush plane. |
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Chris Walterson
Robert----------- On mine I have the trim spring , reflexor and sparrow strainers. I think as long as the sparrow strainers are installed the elevators will ride in trail pretty well, BUT, there is still a bit of force on the stick.
I found once mine was all built, I only needed to set the trim spring initially and then after that I use the reflexor for any trimming. As you can see on the flight test video i posted, I could fly it hands off on the first flight. Everything was set to as close to the plans as I could achieve and it worked well. My little Super Quickie was designed and built to fly without sparrow strainers, but I needed about 2 lbs spring tension to hold the elevators down. Once in flight the elevators went in trail, but Ialways kept the spring tension. Sparrow strainers work and are very important.-------------- Chris -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus |
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David J. Gall
Robert,
You’re asking for a Masters’ level dissertation on pitch stability and control, all of which has been hashed over numerous times on these pages. Please read the archives.
Long story short: follow the plans and the QAC factory plans change notices. We don’t need any Q-pilots (you!) killed because they thought they could do it “better” without understanding what it is that they’re doing. If you’re flying without sparrow strainers (or their aerodynamic equivalent) you’re doing it wrong. If you’re installing an autopilot servo with the expectation that the servo can hold a bias force thereby permitting you to eliminate the spring, you’re doing it wrong. If you’re installing an autopilot without first having hand-flown the full flight envelope and adjusted the trim spring and sparrow strainers (both with and without using the reflexor), you’re doing it wrong.
David J. Gall
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Robert Schmid
Sent: Thursday, July 28, 2022 6:04 PM To: main@Q-List.groups.io Subject: [Q-List] Elevator Trim Springy Thingy Really Needed?
Humor me please, with a little bit of patience as I have only flown a Quickie once ... With a 2 axis autopilot and a reflexor, do I need the elevator trim spring setup at all?
What do I know? Knowing you, I expect a lively conversation so GO :-) |
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Just a clarification on what Chris said. He and I both have the LS1 canard which requires the sparrow strainers. The GU canard that you have doesn’t require them and will be more like the Q1 (GU canard) or the original Long-EZ with the GU canard and will require a small spring force trim on the elevator.
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I think Chris and David’s responses about the sparrow strainers suggests that that they believe you have the LS1 canard. They can correct me if I am mistaken on that. I have both spring-loaded elevator trim and reflexor and find that I use both. Having both allows me to optimize cruise at different cg’s, with only small adjustments. I agree with David that you should not even think about using autopilot until you are very familiar with the hand flying characteristics of the plane in all phases of flight. Cheers, Jay On Jul 28, 2022, at 10:22 PM, David J. Gall <David@...> wrote:
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David J. Gall
“If you’re flying without sparrow strainers (or their aerodynamic equivalent) you’re doing it wrong.”
“I think Chris and David’s responses about the sparrow strainers suggests that that they believe you have the LS1 canard.”
Actually, Jay, I stand by that statement even for the GU canard. But I’m not going to argue with all the Q2’s that are “successfully” flying without sparrow strainers or equivalent. I just bite my lip and move on, hoping they’ll never have a spring failure or a significant overspeed….
David J. Gall
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Jay Scheevel
Sent: Thursday, July 28, 2022 11:13 PM To: main@q-list.groups.io Subject: Re: [Q-List] Elevator Trim Springy Thingy Really Needed?
Just a clarification on what Chris said. He and I both have the LS1 canard which requires the sparrow strainers. The GU canard that you have doesn’t require them and will be more like the Q1 (GU canard) or the original Long-EZ with the GU canard and will require a small spring force trim on the elevator.
I think Chris and David’s responses about the sparrow strainers suggests that that they believe you have the LS1 canard. They can correct me if I am mistaken on that.
I have both spring-loaded elevator trim and reflexor and find that I use both. Having both allows me to optimize cruise at different cg’s, with only small adjustments.
I agree with David that you should not even think about using autopilot until you are very familiar with the hand flying characteristics of the plane in all phases of flight.
Cheers, Jay
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Ok, I stand corrected but there is no published plan for a Q2 GU elevator sparrow strainer, so if Robert were to want to install one he would need to be the first to design and test it. The dragonfly has a sparrow strainer design for its GU canard but that canard has different dimensions, so does not translate on for one.
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Cheers, Jay On Jul 28, 2022, at 11:29 PM, David J. Gall <David@...> wrote:
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Brent Sherstan
Actually, there are a few examples of GU canards with sparrow strainers in the Q-tour archives. Peter Mazsaros and David Smith both had them. Good videos explaining why they seemed necessary as well.
Brent |
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Robert,
I couldn’t agree with David and Jay more. We’ve been watching this scenario play out over
40 +years. Sadly, several people died thinking they knew better than the advise they were given.
Everybody wants a fast and pretty plane but prudence is your best friend. After all it’s your but in the seat.
We didn’t have internet, just a bunch of dedicated guys trying to get those Q birds in the air and we learned from each other. Pioneers like
Sam H., Paul F. Bruce C. Bob Malacek and others before them helped pave the way. Some wouldn’t listen and paid for it.
Like for example, when the guy from New Jersey crashed John Findley’s
Quickie at Albuquerque International and then tried to blame Jon for it. He flew there with another guy to fly it back to NJ.
Like David said, read the archives……... everything you can get your hands on. Not being critical but all the info you are asking about has already been answered multiple
times.
Jim
N46JP - Q200
From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of David J. Gall <David@...>
Sent: Thursday, July 28, 2022 7:22:11 PM To: main@Q-List.groups.io <main@Q-List.groups.io> Subject: Re: [Q-List] Elevator Trim Springy Thingy Really Needed? Robert,
You’re asking for a Masters’ level dissertation on pitch stability and control, all of which has been hashed over numerous times on these pages. Please read the archives.
Long story short: follow the plans and the QAC factory plans change notices. We don’t need any Q-pilots (you!) killed because they thought they could do it “better” without understanding what it is that they’re doing. If you’re flying without sparrow strainers (or their aerodynamic equivalent) you’re doing it wrong. If you’re installing an autopilot servo with the expectation that the servo can hold a bias force thereby permitting you to eliminate the spring, you’re doing it wrong. If you’re installing an autopilot without first having hand-flown the full flight envelope and adjusted the trim spring and sparrow strainers (both with and without using the reflexor), you’re doing it wrong.
David J. Gall
From: main@Q-List.groups.io <main@Q-List.groups.io>
On Behalf Of Robert Schmid
Humor me please, with a little bit of patience as I have only flown a Quickie once ... With a 2 axis autopilot and a reflexor, do I need the elevator trim spring setup at all?
What do I know? Knowing you, I expect a lively conversation so GO :-) |
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Jay,
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My Dragonfly has a GU canard and needs sparrow strainers. On Thursday, July 28, 2022, 9:29 PM, David J. Gall <David@...> wrote:
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Mr Mod himself (me) is staying with the known aerodynamics. I also have a GU airfoil and even though I do not
plan to add an autopilot, the trim system and reflexor are "in stone" along with vortex generators.
I also agree with the others to read all the archives now. Once you get your repair completed Robert DO take the time to
"deep dive" because this machine is unlike others, as you will discover when you taxi up to the pumps on the ramp!! You
have a lot of history to catch up on.. and its' damn good reading too I might add.
Not rolling out resumes..but I know John Roncz, Burt and Dick Rutan, and Jeanna. I was on the R&D team of Starship 1
at Beech in the early 1980's and spoke with John several times. I was building my Cozy at the time and asked a lot about the Q bird.
One of our co-horts was building a Q1 at the time. John Bingham also was in the conversations. At the time I had only flown a
Q1 once in Little Rock. Long-eze on several Xcountrys from Wichita where I was born. Roncz admitted the aerodynamic issues with
the GU to us, having already experienced rain and bug lift
degrading. Its not "bad" per se..but DOES need the generators to be safe.
Due to Flight Testing of NC2 and NC3 Starship ended up having fences on the main wing and vortex generators on the canard in production, which you can clearly
see in this photo op shot.
Take a bit of a break from re construction and just take a few days to injest what experiences are offered free to you. You might even find Sam in a few of those
photos. :-)
Vern
From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jim Patillo <Logistics_engineering@...>
Sent: Friday, July 29, 2022 12:25 AM To: main@Q-List.groups.io <main@Q-List.groups.io> Subject: Re: [Q-List] Elevator Trim Springy Thingy Really Needed? Robert,
I couldn’t agree with David and Jay more. We’ve been watching this scenario play out over
40 +years. Sadly, several people died thinking they knew better than the advise they were given.
Everybody wants a fast and pretty plane but prudence is your best friend. After all it’s your but in the seat.
We didn’t have internet, just a bunch of dedicated guys trying to get those Q birds in the air and we learned from each other. Pioneers like
Sam H., Paul F. Bruce C. Bob Malacek and others before them helped pave the way. Some wouldn’t listen and paid for it.
Like for example, when the guy from New Jersey crashed John Findley’s
Quickie at Albuquerque International and then tried to blame Jon for it. He flew there with another guy to fly it back to NJ.
Like David said, read the archives……... everything you can get your hands on. Not being critical but all the info you are asking about has already been answered multiple times.
Jim
N46JP - Q200
From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of David J. Gall <David@...>
Sent: Thursday, July 28, 2022 7:22:11 PM To: main@Q-List.groups.io <main@Q-List.groups.io> Subject: Re: [Q-List] Elevator Trim Springy Thingy Really Needed? Robert,
You’re asking for a Masters’ level dissertation on pitch stability and control, all of which has been hashed over numerous times on these pages. Please read the archives.
Long story short: follow the plans and the QAC factory plans change notices. We don’t need any Q-pilots (you!) killed because they thought they could do it “better” without understanding what it is that they’re doing. If you’re flying without sparrow strainers (or their aerodynamic equivalent) you’re doing it wrong. If you’re installing an autopilot servo with the expectation that the servo can hold a bias force thereby permitting you to eliminate the spring, you’re doing it wrong. If you’re installing an autopilot without first having hand-flown the full flight envelope and adjusted the trim spring and sparrow strainers (both with and without using the reflexor), you’re doing it wrong.
David J. Gall
From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Robert Schmid
Humor me please, with a little bit of patience as I have only flown a Quickie once ... With a 2 axis autopilot and a reflexor, do I need the elevator trim spring setup at all?
What do I know? Knowing you, I expect a lively conversation so GO :-)
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I may stand corrected.. the D fly chord is greater as well as span? Honestly I have not measured this, but by eyeball they
do appear so. As you know, I want to build different elevators to fit my Canard, Jay..but am fully prepared to add the strainers
too. We will discover that in Phase 1. There are some construction issues on the elevator design that I thought of as a bit of improvement I have seen several
of you fellas incorporated. David has a viable concern on flutter control.
Dynamic balance to engineering. Since I do not have elevators
yet that is a given task. I'm also going to scrap the
one aileron
I have and build a new set because I'd rather know the construction. I'm set up anyway so
not adding that much cost or time.
From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Sent: Thursday, July 28, 2022 10:42 PM To: main@q-list.groups.io <main@q-list.groups.io> Subject: Re: [Q-List] Elevator Trim Springy Thingy Really Needed? Ok, I stand corrected but there is no published plan for a Q2 GU elevator sparrow strainer, so if Robert were to want to install one he would need to be the first to design and test it. The dragonfly has a sparrow strainer design for its GU
canard but that canard has different dimensions, so does not translate on for one.
Cheers,
Jay
On Jul 28, 2022, at 11:29 PM, David J. Gall <David@...> wrote:
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Chris Walterson
Just to stir the pot a bit more. My little Quickie had the GU without the strainers, but needed lots of trim force.
How much trim force does the GU need in the Q2? My GU in the Dragonfly with strainers works well. I would think the strainers would benefit any airfoil to aid in trimming. Not an engineer by any means, but a bit of experience.-------------- Chris -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus |
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So in summary, this was an unanimous response, the "Springy Thingy" is needed, no matter what canard. Btw yes Jay is correct, I have the GU canard so no strainer until flown and seen if needed.
Thanks for your "passionate" responses, Robert -- Robert "TheFrisco" Schmid (408) 805-5450 www.facebook.com/TheFlyingFriscos www.theflyingfriscos.com Love building planes almost as much as flying. Latest completed build is "Loki", a Chinook Plus 2 bush plane. |
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Rick Hole
The elevator spring and sparrow strainer work together to establish a default for elevator deflection which is somewhere within the range of sustainable flight should either fail or elevator linkage fail. The builder should consider failure modes in understanding what each does.
Relying on spring pressure alone, and the spring system fails can, and has, caused catastrophic failure of the aircraft. Sparrow strainers could potentially become attached. Elevator linkages have broken. In all cases we want the elevator to stay in a flyable state. In this event altitude can be controlled with the throttle if necessary to make an emergency landing. Velocities have the same basic issue. I have seen builder omit the sparrow strainer or even (!) install it upside down and flown successfully that way and never seen a failure mode arise. But it only takes once... As for depending on autopilot to hold the elevator, remember they are not designed to continuously provide pressure, only to maintain altitude given a properly trimmed condition. I have seen this principle ignored and pilots go to unusual attitude when the autopilot is disengaged either manually or unexpectedly. It is at best embarrassing in front of passengers and at worse... Rick Hole |
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Sandaircraft
Just stupid non engineer thinking, but on the ls if the issue is from the under camber, if elevators are built without it and built symmetrical wouldnt that elevate the problem or does that change the airfoil too much?
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On Jul 29, 2022, at 10:57 AM, Rick Hole via groups.io <r.hole@...> wrote: |
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David J. Gall
Not stupid at all. That’s almost exactly what John Roncz did in designing the Long-EZ replacement canard airfoil, except he gave it a little “kick” up right at the trailing edge that helps “push” the trailing edge of the elevator “down into the airstream” so to speak. That’s all the Roncz canard needs — no spring, no sparrow strainer — just that little “reflex” (and proper mass balance weights) and the airplane can fly at low, low cruise speed with the elevator control and trim system completely disconnected (not that you’d do that on purpose, of course!).
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That’s the gold standard that we should strive toward while acknowledging that the existing system “works” but (for the GU canard) is deficient and has potentially fatal failure mode(s). The LS-1 canard also has a potentially fatal failure mode if the sparrow strainers break. David J. Gall On Jul 29, 2022, at 12:08 PM, Sandaircraft <Snoboarders@...> wrote: |
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I have been working on this exact item but have not finished anything yet. Once I have something that I believe will work, I will publish it here for discussion.
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Cheers, Jay On Jul 29, 2022, at 12:40 PM, David J. Gall <David@...> wrote: |
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Mike Dwyer
Hi Robert. I had to read your question several times. Please, when you write something like this, let people know that your flying a GU Canard (which doesn't use Sparrow Strainers), and have the aileron reflexer installed... So your asking about should you use the trim springs. Yes. Without the springs, holding 20 pounds your arm will eventually turn to jelly like mine! I also used the springs to reduce the stick force on final thus making a better landing. I don't hear this much from people but on my Q200 in cruise I liked to trim the Reflxer all the way up, which made the forward stick for really high. Think of it this way, if you command less lift from the ailerons (reflex up) then you got to command less lift from the canard (stick forward). So less lift = less drag = mo speed! I used to gain about 4 mph for free doing this. Yes, I needed my trim springs! Mike Dwyer YouTube Videos: https://www.youtube.com/user/FlyMeAirplane/videos Q200 Website: http://goo.gl/V8IrJF On Thu, Jul 28, 2022 at 9:58 PM Chris Walterson <dkeats@...> wrote: Robert----------- On mine I have the trim spring , reflexor and |
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