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Swampyankee

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I see that plane manufacturers are looking at morphing control surfaces. Given the extra complexity, weight and possibles failures, is it worth looking into for our recreational aircraft?
That's a definite maybe ;)


Largely, but not exclusively, recreational aircraft have been very conservative in design as they are designed and built by much smaller organizations -- down to one person -- than are commercial and military aircraft, so we're not likely to see this kind of advanced technology on recreational aircraft soon, so it's more difficult for them to incorporate modern research into their designs.
 

Topaz

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I see that plane manufacturers are looking at morphing control surfaces. Given the extra complexity, weight and possibles failures, is it worth looking into for our recreational aircraft?
I would say it depends entirely on the design mission. For most sportplanes, in my opinion, no, it's not worth it. We get very good utility out of the good-old-fashioned designs, and there's yet a lot of very low-hanging fruit in terms of drag reduction that can be had without resorting to such complexities.

On the other hand, high-performance sailplanes are scratching for every shred of drag reduction they can find, and have long ago gone through the low-hanging-fruit, the middle-hanging-fruit, and are working on the stuff near the top of the tree. "Morphing" control surfaces have already been tried to the limits of then-current technology, but as the concept progresses I think you'll see it increasingly adopted by the glider racing community. It's worth it there.
 

rdj

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I see that plane manufacturers are looking at morphing control surfaces. Given the extra complexity, weight and possibles failures, is it worth looking into for our recreational aircraft?
Isn't that what the Wright Brothers did? Weight, complexity? Have we gone full circle already?
 

TFF

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It will depend on how easy a billion dollar technology can trickle down to the dollar store level. Wanting is nothing special. The question comes, why use something so complicated when most cant build the simplest homebuilt.
 

Victor Bravo

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If you have a really exotic super low drag wing airfoil, and the morphing stretching "living hinge" type control surfaces allow it to get a longer laminar run or change camber over a larger percentage of chord... then fine it is worth it for THAT mission.

It will be a very long time IMHO before the average sport pilot with his Cub or RV type sportplane can make worthwhile use of morphoing or stretching the airfoil.

The "living hinge" to my understanding is using the top or bottom skin of the wing as the aileron or flap hinge. The aileron/flap skin was the same piece as the main wing skin. Zenith tried this on one of the CH200 o 300 aluminum airplanes once as well. The composite version was tried on two or three gliders in the late 1970's and early 190's... the Polish Jantar racing glider and the Grob "Speed Astir". The Speed Astir was Grob's attempt to have a competitive racer, but it was nowhere near the performance of the big three sailplane manufacturers' racing class gliders.

IMHO they used the living hinge on the wrong side of the wing. they should have made the bottom surface the living hinge, because with modern airfoils on gliders you have some realistic chance of having laminar flow back that far on the bottom only.
 

deskpilot

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VB, I have an idea that has "living hinges"(never heard that term before but I like it) on both upper and lower surfaces. Works well for a model but not sure about full size applications. As stated, it's complex, a bit heavier than normal piano hinged surfaces and definitely is heavier to use. Mind you, it has a fail safe to return to zero should control runs have a failure.
 

Riggerrob

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One variation on living hinge used curved carrots to flex the trailing edge. Carrots are cones with bearings at the front and rear ends. They run straight fore and aft from the main spar to the trailing edge.
Try to picture a carrot top attached to the front spar with a bearing that allows it to turn. The trailing end fits into another bearing in the trailing edge. A pulley or cogwheel encircles the Front/fat end of the carrot and connected to control cables. There is an oval/racetrack slot in the rear spar that is slightly larger than the carrot. As the carrot rotates, it raises or lowers the trailing edge dye. It rotates 170 degrees from full up aileron to partial down aileron.
When all the carrots rotate (trailing edge down) the entire trailing edge becomes landing flaps. To turn, raise the trailing edge (aileron) on the inside of the turn.
 
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