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Jointly developed flexible wing design for airplanes

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Except it's not remotely new idea, that's kind of how the Wright Flyer worked if I recall correctly 'wing warping' was the control method (and there were all sorts of law suits that followed up when Curtis went to what we now consider more conventional control surfaces and whether that infringed on their patent etc.).

The dream of a wing configuration that truly adapts to different portions of the flight regime seamlessly has been chased for a long time.

Most attempts such as 'swing wings' or efforts to change camber/aerofoil section etc. come at a significant weight penalty and weight is the enemy of flight so ...

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KENAT, I am ignorant of all things aviation. It came across a news feed and I thought it was interesting, that's all. Pretty simple thinking taking place today. :)

Pamela K. Quillin, P.E.
Quillin Engineering, LLC
 
this actually is different to "wing warping" ... which was an awful way to try and control an airplane (pretty much why we don't use it today).

this is a NASA project about adaptive wings ... instead of using traditional flaps to create a cambered wing section, they're using some "magic" so they they've got a continuous wing skin, and they're deflecting the trailing edge down (and presumably the leading edge too) so that the top of the wing is a smooth continuous curve.

ok, it's not "magic" but clever engineering (which sort of counts as magic; to paraphrase Arthur Clarke, any sufficiently advanced engineering is indistinguishable from magic) ... stretchy membranes, actuators, control system and somewhere enough primary structure to carry the load.

another day in paradise, or is paradise one day closer ?
 
Sorry lacajun, if that came across as a dig against you it wasn't meant to.

rb1957, sure the Wrights used it for control (rather than ailerons) while NASA is using it as a lift device (in lieu of flaps) but these 2 applications have overlap (i.e. flaperons, or the fact that ailerons are differentially increasing/decreasing lift on each wing rather than equally increasing lift on each wing) and fundamentally use the same core aerodynamic principles.

They work primarily by changing the effective angle of attack, to change lift & there's more than one way to skin that particular cat.

(Yes, flaps often increase wing area or introduce things like slots to tweak the aerodynamics but I believe my point stands.)

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A problem as I see it with the flexible skin, is that you can't have a slotted flap or slat, and thus have lower lift efficiency (i.e. too much drag for a given increment of increased lift) and potentially a worse stall condition (stall on a flap can progress to the main wing more easily). There are also some aeroelastic issues with a flexible membrane than can undergo strain softening (Mullin's effect) like most if not all elastomers. Interesting to see if they can work through the issues and still show the benefits touted.
 
Interesting points btrue. It brings to mind the issue many WWII airraft had with fabric covered ailerons. At high speeds (e.g. diving) the fabric control surfaces would 'balloon' impacting control ability.



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Kenat, I agree the Wright's used wing warping for their initial planes, but quickly the aviation world adopted ailerons ... for a reason (ailerons have much better controllability than wing warping).

I agree there are issues with what they're doing, structurally and aerodynamically, but they have tried this before (I think on an F111) and were happy enough with those results to try it again. it may lead somewhere, it may just be a boon-doddle.

another day in paradise, or is paradise one day closer ?
 
Oh it's definitely interesting but there have been other aero projects on the verge of a break thru too that still haven't gone anywhere much.

Active boundary layer control is always the one that springs to mind - I don't mean blown flaps etc. I mean lots of small holes in the skin of the A/C and some kind of 'suction' on the back side.

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Gus Raspet at Mississippi state university developed a composite wing with variable camber in the 1960s; he also developed wings with boundary layer rejuvenation, and a suction type boundary layer control. Some of his ideas were incorporated into other aircraft later.
B.E.

You are judged not by what you know, but by what you can do.
 
Correction the variable camber wing was developed at Mississippi state after Gus Raspet's untimely death.
B.E.

You are judged not by what you know, but by what you can do.
 
The Bucc had a variation on blown flaps if memory serves.

I was talking about something different which is pretty much what I describe. Can be made to work until you try it in the real world and all the holes get filled with bug guts etc.

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I thought it had boundary layer suction, but it seems to have been a fix of both ...
Due to the weight of the aircraft and the small flight decks of Navy carriers the predicted landing speed caused some problems but Blackburn had heard of a system called 'Boundary Layer Control' (BLC), where hot air is bled from the engines and blown over the wing flaps, wing leading edges and tail plane to increase air flow and produce more lift.

another day in paradise, or is paradise one day closer ?
 
KENAT, don't worry about me. I thought it was brusque but not a dig. I am probably being viewed as hypersensitive. :)

Pamela K. Quillin, P.E.
Quillin Engineering, LLC
 
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