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Thread: gap seal and aileron fence testing

  1. #1

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    gap seal and aileron fence testing

    with the hot weather, lack of work, and dead mags on my plane i figured i'd hop on and post some of the test results from different mods ive played with. ive added one mod at a time so that i could isolate their effects. flight testing consisted a series of stalls and acrobatic maneuvers that i feel accentuate the effectiveness of these mods.
    aileron testing is done by using incorrect methods of stall recovery, meaning rather then trying to pick up the wing with rudder in slow flight i am picking up the wing with aileron and leaving the rudder in a neutral torque position and holding elevator back untill it was fruitless to hold it longer.

    aircraft: piper L-4, o200 engine, 74/37mac prop, small super cub CB elevators, stock wing, stock aileorn, J3 rudder, 1250lbs flying weight, flight tests all in the front seat.



    before mods:
    stalls where textbook, upon reaching full back stick the plane would stall.
    when leaving rudder neutral and trying to lift the wing with aileron you will only induce a turn and then spin in the opposite direction.
    on takeoffs with 3/4 tanks or more using full forward stick will not raise the tail.
    with 3/4 or less tanks tail will come off, but tends to settle back to the ground, full forward stick being required the first 20 or so feet.
    during a lazy splitS (45 deg zoom climb with a half snap on top) the wing will reliably and predictably snap in the desired direction.
    at speeds below approx 45mph:
    stalls happen at 38 indicated.
    during hammer heads delayed rudder input (below 30mph) results in noticeably lagged response
    sharps turns on the ground required forward stick, labs of break, and a little power. (typical cub, nothing unusual)


    elevator gap seals.
    with full tanks the tail can be lifted off the ground and held their with no tendancy to settle once rolling.
    in cruise their is a distinct pitch senstivity that can translate into PIO and a heavier workout in turbulance to dampen.
    stalls happen at approx 50% elevator travel as opposed to full back stick.
    upon the stall if the elevator is held full back the plane will snap roll aggressivly and immediatly threaton to go into a flat spin, the rudder is stalled and useless as long as the stick is held back (this was a rather dramatic flat spin entry and i wont be testing this mod is this realm of flight anymore).
    stall decreased from 38 down to 35 indicated.
    leval flight required more down trim.
    landing became a game of feel as 3 point landings happening with only 50% stick travel.
    conclusion of elevator gap seal: its required if i hope to be competitive at valdeze or fly a clipped cub and wanna get full control. however its downright dangerous if your giving instruction or lots of rides. the added effectiveness invites stall spin to final, nosing the plane over, and possibly getting the plane stuck in a flat spin in a tail heavy senerio. i took the elevator seal off right away, i give WAY to many rides and do to much acro to have those added risks.

    rudder gap seal.
    feels like a 20% improvement in effectiveness while taxing.
    sharp turns require much less power and brake.
    hammer heads are much more authoritative, which means you can enter them confidently at slower speeds.
    spin entry and exit is more on demand, particularly spin recovery.
    conclusion of rudder seal: its staying on my plane.
    no noticeable change in the feel of the rudder, its just more effective.

    half assed aileorn gap seal
    i call it half ass because i only sealed from the outer aileron hindge outnound, so about 3 ft total was sealed. the effort was to reduce adverse yaw just at the tips.
    cruise flight: lost about 5 mph in cruise. im suspecting that the vortice from the aileron gap increased all the way to the hindge point.
    stalls: when held in a stall the ailerons remained effective on an unpredictable level. in a stall i got 2-3 chances to lift the wing with ailron, but then it would half snap in the opposite direction, each time this half snap getting stepper untill finaly you are beyond 90 degreee roll and simply diving.
    conclusion: dont waste your time with the half ass seal......lol...... loss of speed and no worthwhile gain in roll control.

    outboard aileron stall fence.
    the stall results where basically identical to the above mentiond half ass seal.
    climb rate improvement of 75-150+ FPM.
    lazy split S is somewhat harder to enter requiring that you scrub off all excess speed otherwisw the wing will not snap on deman, but rather it triesto keep flying.
    cruise speed not tested.
    outboard fence conclusion: for the possible climb performance gain i see it seems like a good idea to leave it on, granted it'd require some more testing to see its actual benefits. however it detracts from the acro capabilities in the cub. it reduces the tendancy to spin which makes it somewhat unpredictable in certain manuvers.

    inboard aileron stall fence and exisiting outboard fence.
    no further climb rate increase.
    slips feel more stable.
    aileron effectiveness is greater, allowing for stepper slips.
    lazy split S's are almost impossible. the wings refuse to snap roll and a split S turns into a lazy barrel roll with a heading change of about 160 deg.
    stalls: aileron authority remains good unless forced in a deep stall at which point the down aileron wing will drop and the plane simply enters a stable spiral dive.

    thats all i got for on wing and tail mods for now. once im back in the air and have more to share ill let people know.
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  2. #2
    skywagon8a's Avatar
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    Quote Originally Posted by bogey View Post

    elevator gap seals.
    in cruise their is a distinct pitch sensitivity that can translate into PIO and a heavier workout in turbulence to dampen.

    Good to know information.

    Quote Originally Posted by bogey View Post
    half assed aileron gap seal
    i call it half ass because i only sealed from the outer aileron hinge outnound, so about 3 ft total was sealed. the effort was to reduce adverse yaw just at the tips.
    cruise flight: lost about 5 mph in cruise. i'm suspecting that the vortice from the aileron gap increased all the way to the hinge point.
    stalls: when held in a stall the ailerons remained effective on an unpredictable level. in a stall i got 2-3 chances to lift the wing with aileron, but then it would half snap in the opposite direction, each time this half snap getting stepper until finally you are beyond 90 degree roll and simply diving.
    conclusion: don't waste your time with the half ass seal......lol...... loss of speed and no worthwhile gain in roll control.
    How was this seal accomplished? Tape to completely stop airflow?
    I have been thinking about something for the ailerons similar to that which is on the trailing edge ahead of the flaps. It is important for air to flow between the ailerons and the wing at certain angles of deflection. With an up aileron the air is scooped by the portion which deflects below the wing and forced up through the gap pushing a slug of air upward thus helping to force the wing down. With a down aileron, some higher pressure air is forced up through the gap and over the top of the aileron. This is where my question originates. The trailing edge of the top of the wing is squared as it is in the flap region. This makes for "dirty" turbulent air. When the gap fairings are installed ahead of the flaps this air is streamlined, smoothing the air flow over the flaps and over the elevators. What about a similar fairing ahead of the ailerons? One that leaves a gap when the ailerons are up but forms a smooth flowing accelerated air flow when the ailerons are down? Streamlining the upper aft section of the wing. More down aileron lift being produced.

    Your thoughts? I may just try this by taping something on just one wing to see what happens. To see if it rolls better in one direction than the other.
    N1PA

  3. #3
    DJ's Avatar
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    This is interesting. Thank you.

    Sent from my SM-G965U1 using SuperCub.Org mobile app
    The heavens declare the glory of God; the skies proclaim the work of His hands. Psalms 19:1

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    TurboBeaver's Avatar
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    Pete did not very early J3's have a factory aileron top seal?
    I think Spruce still offers a kit for sealing the Ailerons. From pictures looks to be bent sorta similar to standard flap seals. I have seen this on 18's numerous times in Ak.
    Can't imagine how a stall fence at the outboard
    Aileron rib could do as this testing implys, interesting stuff.
    I would like to try one between inboard end of ailerons and
    the flaps. Interesting results there as well. Cool stuff.
    EClick image for larger version. 

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  5. #5
    cubdrvr's Avatar
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    Be interesting to see how VG's would affect those test results...............
    "Sometimes a Cigar is just a Cigar"

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    BC12D-4-85's Avatar
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    As mentioned earlier I installed homemade flap cove gap seals in the aileron bay of a PA-18. Seemed to help as the wings were squared off but still close to original span. Ailerons were also squared but not extended outboard.

    Gary

  7. #7
    skywagon8a's Avatar
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    Quote Originally Posted by TurboBeaver View Post
    Pete did not very early J3's have a factory aileron top seal?
    I'd have to look into that. My comments are based upon my TCOW wings. They may or may not match Piper's in this area?
    N1PA

  8. #8

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    the aileron gap seal was just tape on the bottom of the aileron. the tape i used was something a buddy gave to me, its basically 2 inch wide electrical tape but it sticks better and pulls off just as nice.
    the tape seal was litterally just flat on the bottom of the wing. when the aileron is deflected the tape would unstick. then it'd sit flat again once the aileron went back to level. i'd imagine taping both ailerons this way would not be a good idea, might make for for weird control issues if the stick fights ya.

    i know the taylor E-2 cub's had a update that recommended or required sealing the aileron gaps in order to improve climb capability. im not sure if this seal was on, J-2, and or early j-3's.

  9. #9
    skywagon8a's Avatar
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    I just did a yarn test on the aileron. Yarns taped to the trailing edge of one aileron and the wing tip. As the stall was approached the yarns started to dance around then just prior to any indication of a stall they completely reversed disappearing above the aileron. Definitely some airflow reversal at minimum speeds indicating loss of aileron effectiveness at low speed. It would be nice to be able to look at the top of the wing to see what the yarns were doing. The way they quickly all completely disappeared gave the impression they were facing forward.

    Next step I'll yarn test the flaps to see what happens during a flaps up stall. The flaps have a good fairing which closes the gap when up.
    Last edited by skywagon8a; 08-07-2022 at 02:12 PM.
    N1PA
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    akavidflyer's Avatar
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    split S is just a half roll then half inside loop, there shouldn't be a snap in it and if there was it would deduct from a score.

    Gap seals on the elevator being dangerous?? There are a metric **** ton of guys that would disagree with this including me. I have flown light and at gross and never once have I thought to myself, damn this plane just has way too much elevator authority I need to tone that down a bit.

  11. #11
    skywagon8a's Avatar
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    Quote Originally Posted by akavidflyer View Post
    Gap seals on the elevator being dangerous?? There are a metric **** ton of guys that would disagree with this including me. I have flown light and at gross and never once have I thought to myself, damn this plane just has way too much elevator authority I need to tone that down a bit.
    All airplanes are not exactly the same. What is good or bad for one doesn't necessarily apply to another. Sometimes just the littlest thing can create an issue or not.
    N1PA

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    akavidflyer's Avatar
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    Quote Originally Posted by skywagon8a View Post
    All airplanes are not exactly the same. What is good or bad for one doesn't necessarily apply to another. Sometimes just the littlest thing can create an issue or not.
    ok, cubs, or cub types seem to benefit from the seals. Except for this one, I don't know of anyone who has had them on say they wish they didn't install them.
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    BC12D-4-85's Avatar
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    If I wanted to see the wing's top I'd mount a camera to my Atlee Dodge seaplane lift tabs that permanently extend above the root fairing. Or to the tail beacon above the rudder, if I had one. Just some ideas.

    Gary

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    Jerry Burr's Avatar
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    Skywagon. Put some tufts on the bottom of the wing in front of the aileron false spar. 2 inches ahead of the slot and long enough to reach 2 inches back on the aileron. Watch them when you slow to slow flight. Jerry
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  15. #15
    skywagon8a's Avatar
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    Quote Originally Posted by Jerry Burr View Post
    Skywagon. Put some tufts on the bottom of the wing in front of the aileron false spar. 2 inches ahead of the slot and long enough to reach 2 inches back on the aileron. Watch them when you slow to slow flight. Jerry
    Will do. That will tell us whether the air flows up through the gap, which it should.
    N1PA

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    cubdriver2's Avatar
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    Quote Originally Posted by BC12D-4-85 View Post
    If I wanted to see the wing's top I'd mount a camera to my Atlee Dodge seaplane lift tabs that permanently extend above the root fairing. Or to the tail beacon above the rudder, if I had one. Just some ideas.

    Gary
    Careful what you do above above the windshield. I had a fairing come loose a few inches and and it stalled the tail below 70mph

    Glenn
    "Optimism is going after Moby Dick in a rowboat and taking the tartar sauce with you!"

  17. #17
    BC12D-4-85's Avatar
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    Caution is prudent. I'd install a camera where we already install antennas. I'd also try to fair the camera's shape to reduce turbulence.

    Gary

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    cubdrvr's Avatar
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    Extended flap gap seal..........

    Click image for larger version. 

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    "Sometimes a Cigar is just a Cigar"

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    BC12D-4-85's Avatar
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    ^^^^That's what I did to my last PA-18, plus sealed the lower hinge openings for the flaps and ailerons as much as possible. My thought was to keep as much of the air under the controls as possible at high AOA when the upper surfaces were likely in turbulent flow. Newton's 3rd etc.

    Gary

  20. #20
    skywagon8a's Avatar
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    Tuft Test
    It's not easy holding a cell phone camera at minimum speed and getting it to take a picture when you want it to do it. So, the one which was supposed to be at minimum speed ...... wasn't. You'll have to take my word for what I saw. The trailing edge tufts went up out of sight. The lower ones under the wing continued to flow straight back never showing a tendency to flow up into the gap. This along the full span of the aileron.

    The first picture shows a gap fairing which shaped that portion of the trailing edge into a venturi to direct higher velocity flow over the top of the aileron. At minimum speed I moved the ailerons rapidly first in one direction, then the other in order to attempt to discern a difference in roll authority. There may have been a microsecond difference in roll rate ...... maybe. Certainly not enough to install a full set of fairings.

    Click image for larger version. 

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    N1PA
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    BC12D-4-85's Avatar
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    Maule made the gap fairing full wing length. I ended up liking the mod but not done for roll rate....just some more lift (maybe). With VG's stall was upper 20's GPS GS level flight no wind PA-18A gross weight.

    Gary

  22. #22
    skywagon8a's Avatar
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    Quote Originally Posted by cubdrvr View Post
    Extended flap gap seal..........

    Click image for larger version. 

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    Quote Originally Posted by skywagon8a View Post
    Tuft Test
    It's not easy holding a cell phone camera at minimum speed and getting it to take a picture when you want it to do it. So, the one which was supposed to be at minimum speed ...... wasn't. You'll have to take my word for what I saw. The trailing edge tufts went up out of sight. The lower ones under the wing continued to flow straight back never showing a tendency to flow up into the gap. This along the full span of the aileron.

    The first picture shows a gap fairing which shaped that portion of the trailing edge into a venturi to direct higher velocity flow over the top of the aileron. At minimum speed I moved the ailerons rapidly first in one direction, then the other in order to attempt to discern a difference in roll authority. There may have been a microsecond difference in roll rate ...... maybe. Certainly not enough to install a full set of fairings.

    Click image for larger version. 

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    I need to amend the above comments. From what I could see of the yarn tuffs this fairing did nothing. I left a 13" section of the fairing in place Click image for larger version. 

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    the opposite aileron was down slightly in cruise. Like this. Click image for larger version. 

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    Then I removed the fairing and the aileron was like this in cruise. Click image for larger version. 

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ID:	62323 Conclusion: The fairings that cubdrvr has deserve some investigation. If that 13" section on my Cub creates enough extra lift for that much aileron deflection, how much lift would the full fairing produce? What else would it do? Would there be a roll rate improvement?
    N1PA
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  23. #23
    frequent_flyer's Avatar
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    Quote Originally Posted by skywagon8a View Post
    I need to amend the above comments.

    Conclusion: The fairings that cubdrvr has deserve some investigation. If that 13" section on my Cub creates enough extra lift for that much aileron deflection, how much lift would the full fairing produce? What else would it do? Would there be a roll rate improvement?
    The roll observed with only one wing having the improvement can be quite informative. Many years ago I converted my ASW-19B glider from factory style fabric aileron seals to mylar seals. I only had time to do one side before I wanted to fly it next. There was a noticeable roll away from the mylar sealed wing.

    The fabric and mylar seals both covered the top of the aileron gap but the fabric seals had a recessed curvature to allow aileron movement. The mylar seals were flat when there was no aileron deflection and flexed to follow the aileron when it was moved.

  24. #24
    BC12D-4-85's Avatar
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    When I made mine I had a local sheet metal shop roll four pieces of aluminum. Then they folded a portion back over the outside of the curved surface in a brake. I had a piece of flap gap seal as a pattern for them. Installed they need to allow upward aileron travel while maintaining a flow gap similar to what the flap seals provide.

    Gary

  25. #25
    skywagon8a's Avatar
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    Quote Originally Posted by BC12D-4-85 View Post
    When I made mine I had a local sheet metal shop roll four pieces of aluminum. Then they folded a portion back over the outside of the curved surface in a brake. I had a piece of flap gap seal as a pattern for them. Installed they need to allow upward aileron travel while maintaining a flow gap similar to what the flap seals provide.

    Gary
    There should be a gap on the ailerons for a slot effect but the flap's gap should be closed when they are up, opening only when not up to provide a slot for extra flap lift. Now what size should the aileron slot be? My test piece is about 1/4".

    That 1/4" gap on my aileron remained constant while the aileron moved full travel.

    My flaps have a teflon strip on the bottom of the wing trailing edge to prevent chafing when they are up.

    Has anyone placed this fairing on just one aileron for the full span? Since only 13" created that much lift what will the full span do?
    N1PA
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    BC12D-4-85's Avatar
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    Many if not most Piper flap seals aren't totally closed against the flaps. There seems to always be some gap - 1/8-1/4" typically. I assume that's to reduce wear over flap fastener heads and prevent contact freezing in wet/cold climes. Beating on them to remove ice and snow causes further deformation. If installed over the ailerons the needed spacing for up travel created the small clearance gap you're describing for my experiment. Never did the one side only test. Stories of other one sided mods (cuffs and others) discouraged that (one wing quits while the other flys). Also seal any gaps around the flap or aileron hinges to keep air under the wing.

    Gary

  27. #27
    BC12D-4-85's Avatar
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    Example

    Gary
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

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  28. #28
    skywagon8a's Avatar
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    Quote Originally Posted by BC12D-4-85 View Post
    Stories of other one sided mods (cuffs and others) discouraged that (one wing quits while the other flys).
    Gary
    During the 80s when I was spending a lot of time in Alaska, I was told of a fellow who for reasons which slip my mind, flew out to a remote location in an -18 with a Cal Center cuff on one wing only. When he took off from that location, the party was over. His life ended. As you are aware I tested my wing tips one wing at a time. I did it knowing there could be a drastic difference. My pond is also over a mile long which gives me enough opportunity to come to the proper conclusion in a timely manner. Knowing the potential for disaster, I take precautions to ensure my safety.

    These pics show my flap gap, the aileron gap and both of them together. As you can see there is a large gap in front of the aileron. Clearly from the experiment described above, some lift is lost here. The flap gap fairing is made from balsa wood covered with fabric. The flap was used as a sanding block on the balsa to get a close fit. I'll have to think about what to do with the aileron gap and what materials to use. Should it be a rounded trailing edge as you described or should it be a thin sharp edge similar to my flaps? To bend aluminum tight back against itself as you had done requires a large radius or a very soft aluminum to prevent cracking.

    Click image for larger version. 

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    N1PA

  29. #29
    BC12D-4-85's Avatar
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    I suspect the material used was 0.020 SO as I don't recall any issues with later cracking. Of course two components - one curved and the other flat could be somehow bonded with that double sided 3M tape Stewart has mentioned. You may be just as well served with a flat top plate for a seal, providing the aileron cove already has some curve back towards the upper exit. Even if it flexes up a little under pressure from below the small gap formed may help energize the aileron's upper LE. I like UV resistant thin polycarbonate for some reason, but metal would work. PM sent earlier as well.

    Gary

  30. #30
    skywagon8a's Avatar
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    Here is a test aileron gap fairing installed on the right aileron.

    Click image for larger version. 

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    This is the right wing with the gap fairing. Click image for larger version. 

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    This is the left wing without an aileron gap fairing. Click image for larger version. 

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    This is what was used to attach the fairing. Click image for larger version. 

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    Temperature in the high 60s, cooler than the above tests produced the same cruise speed using 21" mp instead of 22.5".

    First test at cruise speed of 108 mph to check for more or less lift. Nothing noted.
    Second test, power idle stall trimmed at 50 mph, flaps up. Stall break straight ahead ... no wing drop.
    Third test, trim at 50 mph, power idle full hard aileron left then right. no noticeable difference in roll rate.
    Tuft test, same result as in post #9.

    Conclusion, no observed difference...... waste of time. Might as well take it off.
    N1PA

  31. #31
    BC12D-4-85's Avatar
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    Pete, do your overall aileron gaps and aileron form duplicate Piper's dimensions? The next evolution might be increasing the LR radius of the aileron (fatter than the trailing edge of the nearby wing) similar to CC and Husky? Tape on material and test?

    Earlier: https://www.supercub.org/forum/showt...Aileron-Design

    Gary

  32. #32
    skywagon8a's Avatar
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    I believe the airfoil shape and size is identical to Piper's. I don't have access to a Piper -18 to make a direct comparison of the gap and wing trailing edge cove shape. The performance and handling as is is very acceptable.
    N1PA

  33. #33
    Jerry Burr's Avatar
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    If you are going to test an item on one wing only, your feet have to be flat on the floor or the test is not valid. Your rudder input, even though unintentional changes the results. Do the same to both wings and you will have good data. Also do your tests as close to gross weight as possible. A lightly loaded Cub wing really doesn't really care what you do it. Especially if the item is small. Jerry
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  34. #34
    skywagon8a's Avatar
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    The feet were both flat on the floor and on the rudders. It was done on one wing in order to determine whether there was any more or less lift created. It was loaded lightly. I'll fly it again fully loaded.
    N1PA

  35. #35
    DJ's Avatar
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    Could you do a fully loaded climb test? Maybe 60 or 65 mph

    Sent from my SM-G965U1 using SuperCub.Org mobile app
    The heavens declare the glory of God; the skies proclaim the work of His hands. Psalms 19:1

  36. #36
    skywagon8a's Avatar
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    Looking for what? It climbs like a homesick angel depending upon the prop pitch setting.
    N1PA

  37. #37
    DJ's Avatar
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    Looking for better lift when climbing high and heavy. An improvement of 50 fpm would have me trying the fairing. Same for those cool wingtips

    Sent from my SM-G965U1 using SuperCub.Org mobile app
    The heavens declare the glory of God; the skies proclaim the work of His hands. Psalms 19:1

  38. #38
    skywagon8a's Avatar
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    DJ,
    In my view the aileron gap fairings do nothing. At least on my plane. Your best improvement for altitude performance would be more wing span. My current span is 41' 8". You could copy my wing extensions now during your build by building in the components and covering with fabric. This would save some weight. Mine was made in two separately removeable sections as an afterthought. If I were to do this again I would use the method which was done on Dave Caukins' wings.



    Jerry,
    The feet on the floor test produced so much adverse yaw in both directions, there was nothing to be learned. I think a better improvement for a Cub would be changing the aileron throw to produce more up travel than down, differential travel. That I believe would require changing the aileron control horns. Perhaps even creating an opening in the trailing edge to enable more up travel? I thought of that during the build. Getting the build finished was more important than a major modification in this area at the time. As it is now, there are no aileron travel limiting stops so the travel is set as far as the controls can push them. The lack of differential is noticed.
    Last edited by skywagon8a; 09-22-2022 at 05:25 AM.
    N1PA
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  39. #39
    Jerry Burr's Avatar
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    8a. Yes, the yaw is my point. When you correct for it the results are not accurate. Examples. Slow on final, starts to drop a wing, do you use aileron or rudder? The rudder corrects the problem, the problem you are trying to measure. When testing in experimental, I fastened a 1x4 between the outboard end of the lift struts on the right wing. I then attached a 30 lb block of lead to the 1x4. I had 4 different sets of wingtips to test. The plan was to put a wingtip on and fly slower and slower to see what airspeed the tip let go. Then repeat with all the tips plus no tip. ( flat end ). I had to keep my feet flat on the floor for the above reason. As I slowed down the left wing gave way and it rolled left. The 30 lb weight was the light wing. After six or seven tries it was obvious that p-factor at that speed and attitude was the controlling force. I went back and put each set of tips on both wings and got the results I was looking for. When you make small changes on one wing the results are just not massive. As I found some tests are just not valid. Jerry
    Thanks flynlow, cubscout, bcone1381 thanked for this post
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  40. #40
    skywagon8a's Avatar
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    Flew it loaded today in smooth air. 1924 lbs @ 17.6". This is a widebody injected 180 hp, Whirlwind 200G prop, -18 clone on floats with two different sets of wing extensions and 110" flaps. The inboard aileron hinge is in the same location as the center hinge on a stock Cub. Aileron span is less than a stock -18.

    At cruise speed, 21"mp/2400 rpm 108 mph IAS, the wing with the aileron gap seal was maybe a touch heavy.
    Power idle, full nose up trim at 59-60 mph IAS, reduce speed at the standard 1 mph/second rate. Stall, the right wing started to settle first each time. This was not an abrupt stall.
    At the same power/trim condition full aileron was applied in each direction. Counting 1,2,3,4,5,6,7 to a 30* bank angle. Same imprecise rate in both directions.
    Even with the large ventral fin, rapid full aileron movement in both directions provided excess adverse yawing without rudder input. Definitely, the lack of differential aileron travel is the culprit.

    This airplane is rigged correctly, so any change in lift should show in a requirement to adjust the rigging. Minimal to none was noted.

    Conclusion: The aileron gap fairings only provide a cosmetic change. I may as well remove this one and call it a day. It does close the gap and provide a neater appearance.
    If I was covering a wing, I would make a fairing using Balsa wood sheet then covering it with fabric. Just for appearances sake.
    N1PA
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