Strainers
Chris Walterson
I am attaching a photo of the strainers on my dragonfly. They are about fourteen inches from the elevator tip. Any reason why I can't install them on the Q200 in the same position? Curious Chris
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Why would you do that Chris? The strainers seem to work quite well in the original position. Just curious.
Jim N46JP -Q200 - Airborne Today.
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Chris Walterson
Jim--------- The reason I ask about the strainers, is that they look like a step to look inside to a 10 year old.
On another topic, I was reading some of the old newsletters and saw where one fellow added another 2 degrees of incidence into his canard on his Q200 to get it to fly better. Should I change the incidence.? I have read nowhere else , others having problems. I have the digital levels and all the lazers so I can get it very precise. I would think built to plans is fine. Seeing as Sam has just finished his new canard, and he gets SPEED , maybe he can speak up. For another update. I have my fuselage together with the tail spring, stab and rudder installed.[ Mass balanced]. Have the header and main tank installed. Did a balloon test on both tanks and came back successfully. I have the reflexor built and the tail detachable. Elevators and ailerons finished. Starting to manufacture the dual control setup Canopy hinges next. Any body want any pictures let me know and I'll send them along. Still having fun---------- Canada Chris
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Matthew Curcio
I have seen some that have the strainer at the mid span but in that case they give the strainer more span as it is presumably less effective when out of the prop wash. I have had multiple close calls even with people who should know better trying to use the
strainer as a step so I kind of think moving it out is a good idea despite the weight penalty.
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On that note I have not read in the manual how it advises to set AOI of the strainer but I suspect it may be vague. I have asked around on this subject a bit because my q is quite divergent in pitch. I can get it trimmed out decently in roll and pitch
but it’s more of a balancing act than anything, especially in pitch. I’m fairly certain this has to do with the strainer. This is an especially unsafe characteristic since the q trims the feel of the stick not the control surface. It’s one of the items on
my list of things to sort out. If I was building a q I would leave the strainer unfinished before first flight and build it such that you could adjust the angle before permanently glassing it in place. At some point, during phase one flight testing, do a series
of pitch doublets with varying AOI on the strainer to find the best angle. Matthew Curcio
419-290-3773
On Jan 21, 2018, at 7:38 AM, Dorothea Keats dkeats@... [Q-LIST] <Q-LIST@...> wrote:
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A few of reasons:
1. To exert the same torque, the attachment arms would have to be lengthened (to retain distance from hinge line) which would make them more fragile. I am aware of at least one incident where a strainer, built per plans, broke off in flight by shearing the attachment arms. I have beefed mine up, so even if a 10 year old stepped on it, it probably would not break. 2. The strainer trims out the moment caused by the under-camber in the trailing edge of the LS-1 airfoil. It cancels this force when in neutral trail. However, when the elevator is deflected down or up, the strainer resists this deflection. The resistance introduces additional torque that must be overcome by the torque tube. Having the strainer inboard near the attach point of the steel and aluminum torque tube doubler means less load on the foam outboard of the strainer. Maybe that is the reason that the D-fly requires an extra beef-up on the inboard end of the elevator. 3. Any assymetry from side to side has minimal roll impact when mounted inboard, not so outboard 4. Like Jim said: It works just fine where it is. Cheers, Jay Scheevel, Tri-Q, still building
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Hi Matthew,
Don't confuse the strainer with a trim device. It is only there to try to even up the elevator control forces. The reason you are experiencing a balancing act to get the plane trimmed up in cruise is because the main wing has largely been unloaded with your configuration, so the pitch is primarily controlled by the canard. This makes it a bit touchy. Try introducing a little up reflexor in cruise, then trim the elevator above neutral and I think you will find the pitch more stable because you will be "cradled" between two lifting surfaces instead of balancing on just one. As a side note, if you send me a photo of your plane taken from the side standing about 20 feet from off the wingtips and looking perpendicular to the fuselage (stand midway between the projected/extended canard and main wings), then I can tell you what your decalage is. This is useful to know, when comparing your plane's behavior to other flying Q's. Decalage: http://n8wq.scheevel.com/documents/Scheevel_impact_of_decalage.pdf Cheers, Jay
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Put a NO STEP decal on the strainers. I once had an army officer try and use mine as a step and it broke. Was able to fly it home and the repair was no big deal. I say do it per plans. Like Jay mentioned, I think the reason they are close to the fuselage is to better exert torque to the elevator and torque tubes. Did you know there was a Q-200 fatality due to failure of the mid-elevator support. Yes, the builder did a poor job of executing that part of the construction process, but I could see a sparrow strainer adding more stress and wear to the mid-span pivot. And yes, it is good practice to make it adjustable during flight testing. I think the sparrow strainer design, as provided in the QAC Q-200 plans, has way too much angle of attack. Sam Hosksins
On Mon, Jan 22, 2018 at 10:32 AM, jay@... [Q-LIST] <Q-LIST@...> wrote:
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Jerry Marstall <jnmarstall@...>
At a fly and I turned around to see a fellow getting ready to put his foot on my strainer. I had a "NO Step" decal on mine. I hollered at him and he said it says "STEP ON". I immediately removed the decal Sent from my Verizon, Samsung Galaxy smartphone
-------- Original message -------- From: "Sam Hoskins sam.hoskins@... [Q-LIST]" <Q-LIST@...> Date: 1/22/18 2:10 PM (GMT-05:00) To: Quickie List <Q-LIST@...> Subject: Re: [Q-LIST] Re: Strainers Put a NO STEP decal on the strainers. I once had an army officer try and use mine as a step and it broke. Was able to fly it home and the repair was no big deal. I say do it per plans. Like Jay mentioned, I think the reason they are close to the fuselage is to better exert torque to the elevator and torque tubes. Did you know there was a Q-200 fatality due to failure of the mid-elevator support. Yes, the builder did a poor job of executing that part of the construction process, but I could see a sparrow strainer adding more stress and wear to the mid-span pivot. And yes, it is good practice to make it adjustable during flight testing. I think the sparrow strainer design, as provided in the QAC Q-200 plans, has way too much angle of attack. Sam Hosksins On Mon, Jan 22, 2018 at 10:32 AM, jay@... [Q-LIST] <Q-LIST@...> wrote:
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This is why I am going to put a sticker of Yosemite Sam's pistol, saying BACK OFF! on mine.
Cheers, Jay
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I believe Bruce Crain has his strainers mid span but don't quote me on that I've seen to many Q's over the years to remember them all in detail. Here is a photo of one of ours with a small turn buckle for adjustment. We use to have another with a slotted hole in front for adjusting.
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You should just put the word “DON’T” on it because whoever is looking at it is already thinking about using it as a step, even though it doesn’t seem to lead to anywhere.
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Phil
On Jan 22, 2018, at 1:10 PM, Sam Hoskins sam.hoskins@... [Q-LIST] <Q-LIST@...> wrote:
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Jerry Marstall <jnmarstall@...>
Good idea Sent from my Verizon, Samsung Galaxy smartphone
-------- Original message -------- From: "Phil Lankford britmcman@... [Q-LIST]" <Q-LIST@...> Date: 1/22/18 6:07 PM (GMT-05:00) To: Q-LIST@... Subject: Re: [Q-LIST] Re: Strainers You should just put the word “DON’T” on it because whoever is looking at it is already thinking about using it as a step, even though it doesn’t seem to lead to anywhere. Phil
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I believe Bruce Crain has his strainers mid span but don't quote me on that I've seen to many Q's over the years to remember them all in detail. Here is a photo of one of ours with a small turn buckle for adjustment. We use to have another with a slotted hole in front for adjusting.
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funny story Bruce. I love it! Cheers, Jay Sent from my Verizon Wireless 4G LTE DROID "'jcrain2@...' jcrain2@... [Q-LIST]" <Q-LIST@...> wrote: Yes my strainers are at about midpoint on the elevators. They were probably overbuilt slightly but still won’t make it if stepped on. I have flown them for years so I couldn’t tell you if they work better than inboard. I originally made them adjustable and thought they were going to work. But I had an add on trailing edge flap upward to make them neutral in cruise (the bolt heads and rough texture produced a drag upward on the elevator without the flap). I believe Bruce Crain has his strainers mid span but don't quote me on that I've seen to many Q's over the years to remember them all in detail. Here is a photo of one of ours with a small turn buckle for adjustment. We use to have another with a slotted hole in front for adjusting.
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quickieaircraft
That's a remarkable story. I think the lesson is that sanding things off your plane makes it fly better.
-if TriQ200 ~60 hrs ish if i remember right
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Oh goodie! I have been sanding for months now. I should go really fast and be fully trimmed. Sent from my Verizon Wireless 4G LTE DROID "quickieaircraft@... [Q-LIST]" <Q-LIST@...> wrote: That's a remarkable story. I think the lesson is that sanding things off your plane makes it fly better. -if TriQ200 ~60 hrs ish if i remember right
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Jim D
Initially had the strainers inboard but found the air flow over them intermittent due to propwash. I moved them to mid span and it solved the problem.
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Jim. N56DW TRI-Q with C-85 Sent from my iPod
On Jan 23, 2018, at 6:45 PM, Jay Scheevel jay@... [Q-LIST] <Q-LIST@...> wrote:
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Chris Walterson
I made up my elevators a bit different. I have two hinges in the middle equally spaced instead of just the one. I also have a center hinge on the ailerons. My other airplane I have the strainers set at 30 degrees relative to the top of the elevator. Worked great from day one. I think I saw where Sam set his at 20 degrees so that is where I will start.
I had a little Super Quickie [503] and it had no sparrow strainers. First flight with CG in the middle it took a few pounds of back pressure to maintain level flight. To get it to fly hands off, I needed a lot of down spring pressure on the trim. In level flight the elevators would be neutral, but only with down trim spring. I think sparrow strainers would of made it more managable. It is nice building a 40 year old kit plane. Lots of experience and knowledge out there. Thanks for your input. Chris
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