Folding wings without disconnecting controls?

Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by cluttonfred, Mar 9, 2019.

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  1. Mar 9, 2019 #1

    cluttonfred

    cluttonfred

    cluttonfred

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    Does anyone have any nice photos or clear drawings of wing folding systems that avoid having to disconnect/reconnect flight controls? No, I don't mean eliminating ailerons or flaps, I mean folding wings without having to disconnect/reconnect the controls to the ailerons and flaps.

    7ghz0.jpg
    Source: https://aviation.stackexchange.com/...atic-control-connections-and-how-does-it-work

    I have seen drawings of systems like the one above on sailplanes, but they seemed pretty elaborate. I would be particularly interested in simple solutions, perhaps something a basic as cables that go slack when the wing is folded but are taught once the wing is back in place.

    Cheers,

    Matthew
     
  2. Mar 9, 2019 #2

    Tiger Tim

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    Possible sources to check out for wings folding back: Avid Flyer or pretty well anything strut braced, fabric covered and English.

    Wings folding up: WWII carrier planes expose the guts of how it all works when the wings are folded, lots of pictures online.

    The gold standard of head scratchers: figure out how the controls automatically do their thing on a Grumman Sto-Wing.
     
  3. Mar 9, 2019 #3

    Hot Wings

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    They do look elaborate but in reality they aren't too hard do design/build with modern CAD/CAM. Making all of the little bits by hand is a chore. The only problem I see with this method is that one of the parts ends up with the connecting arms exposed and subject to damage from ground handling when seperated.

    We have had some rather comprehensive threads here on HBA on this subject but with our search function broken, history is not available.

    2 simple options, both with their own problems:

    Teleflex cables.

    Fold like the Onex.

    As Autoreply noted, when he still posted, slop in the control system can lead to flutter.
     
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  4. Mar 9, 2019 #4

    Toobuilder

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    There was a version of the Nesmith Cougar with folding wings. IIRC, it did not disconnect the flaps/ailerons when folded.
     
  5. Mar 9, 2019 #5

    Deuelly

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    Sonex Onex system is similar to the Grumman system. They both have paddles on each section of wing that pivot on concentric shafts when the wings are unfolded.
    Onex-1X-Wing-Fold-OSH10.jpg
     
  6. Mar 9, 2019 #6

    Chilton

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    Take a look at the DH60 Moth, the aileron cable routing from the underside of the fuselage to the inboard rib goes slightly forward, entering the wing just ahead of the rear spar root fitting. When the wing is folded the entry to the wing moves back and out so the tension is almost unchanged.
     
  7. Mar 9, 2019 #7

    Victor Bravo

    Victor Bravo

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    Avid Flyer, as mentioned previously.

    I have owned two sailplanes with the automatic system shown in the OP drawings, and it worked perfectly through hundreds of assembly-disassembly cycles. It even has an adjustment to tighten up the tolerance to address wear in the little roller bearings.

    Why does Autoreply not post here anymore? Did he get PO'd at something or someone? Did he get transferred to living on a remote island without internet access?
     
  8. Mar 9, 2019 #8

    BJC

    BJC

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    I don’t have any photos of mine, but the Sportsman 2+2 folds without having to disconnect any of the the fuel, pitot, wiring, flaps or aileron cables.

    See https://m.youtube.com/watch?v=fLjuZ_5XoBk


    BJC
     
  9. Mar 9, 2019 #9

    Daleandee

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  10. Mar 9, 2019 #10

    ypsilon

    ypsilon

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    The standard automatic connectors on Sailplanes were originally developed by Eugen Hänle (Glasflügel) and are thus called Hänle Tüten in German.
    Also have a look at the Stemme S10 folding mechanism. Looks quite reasonable to me.
     
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  11. Mar 9, 2019 #11

    BJC

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    What is a typical Vne for a high performance sailplane with automatic control connections? (BoKu’s, on the HP-24, look very robust.)


    BJC
     
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  12. Mar 9, 2019 #12

    Himat

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    Could be he got a full time day job, wife and kids. At least that would be my guess.
     
  13. Mar 9, 2019 #13

    Hot Wings

    Hot Wings

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    "Life" happens to all of us at one time or another. For most of us, no matter how much we like the hobby, if it isn't part of our day job it's really pretty far down the list of things that need to be done.
     
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  14. Mar 9, 2019 #14

    ypsilon

    ypsilon

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    250-290 km/h
     
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  15. Mar 10, 2019 #15

    bifft

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    I like this page for Sto-Wing pictures: http://thanlont.blogspot.com/2011/03/grumman-sto-wing-redux.html

    Been leaning toward the cables running on the axis or rotation method as fairly simple. Would be tricky to get both aileron and flaps in the limited space.
     
  16. Mar 10, 2019 #16

    BJC

    BJC

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    Some limited degree of cable slack is not a problem if the pulleys are properly guarded.


    BJC
     
  17. Mar 27, 2019 #17

    autoreply

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    When you typed this, my chin was dragged through the mud by a parapente. Converting my business from engineering consultancy to a production organisation plus a full-time job takes some time. I guess in general, I don't tend to respond to threads I read unless I have something new to offer.


    And I do for this thread. Here is a summation of what would be my priorities based on assembling and disassembling planes for hundreds of times, seeing a few crashes because of it as well as having been exposed to all the fault modes:

    https://www.homebuiltairplanes.com/...rs-for-inexpensive-storage.15935/#post-179716

    Personally I wouldn't settle for any mechanism that doesn't meet all the criteria.
     
  18. Mar 28, 2019 #18

    Sockmonkey

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    A lifting tail design has an edge in this area if the main wing is one removable piece. Using ailerons for both pitch and roll means the runs for them don't go through the fuselage, so you can just unscrew the joystick when the wing needs to come off.
     
  19. Mar 28, 2019 #19

    saini flyer

    saini flyer

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    Jarno, good to hear again from you. I am happy that you have not left this portal.
     
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  20. Mar 28, 2019 #20

    KAF

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    The Europa had a pretty clever control setup, though it is a removable wing instead of a folding wing. I can't seem to locate a decent picture at the moment.
     

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