Air Force to Test Aeroelastic Wings

firegate writes "The New Scientist is reporting that the US Air Force is planning to test a variant of the Wing Warping steering system used on the original Wright Brothers plane to steer new supersonic jets. They've invested $41 million in the project so far, and the first test flight will take place next month at NASA's Dryden research center in California."

More information on the subject...

[prisen]

I'm a USAF member, and at the office lately we've been tossing around this interesting subject. Honestly, the article presented in the story was pretty lame; here's a few good links we've come up with, if you want to know a bit more about the technology:

NASA Press Release [nasa.gov]
Air Force Research Laboratory brief [afrlhorizons.com]
AAW photo collection (NASA) [nasa.gov]

wing warping...

[tanveer1979]

There is a very intersting applet [nasa.gov] about wing warping on NASA site.

Actually wing warping was discontinued due to the fact that as modern airplanes became bigger and heavier rigid Duralium(Aluminium+Copper) and steel was used, which was not very conductive to bending, But I guess with carbon fibre based materials that will change.

Wing warping gives a large degree of control. It is Demostrated very well in the java applet which shows the lift, the forces, the mechanics and the attitude on a model plane(like the one used by wright brothers).

A little history... and a further resource

[DaedalusLogic]

We are a little over a year away from the centennial of powered flight. The Wrights made their first successful powered flight on December 17th of 1903. The first run was something around 12 seconds... Later in the day they recorded durations of just short of 1 minute. The wing warping technique was used to control the roll of the airplane. The Europeans later developed the control surfaces known as ailerons to get around patents that the Wright Brothers had made on their wing warping technique. Ailerons eventually became the method of choice for future development for many engineering reasons.

An article on this matter was published and graces the cover of the September 2002 Aerospace America magazine. The plane this system is being tested on if not intended for is the F-18, the writer of the article was J.R. Wilson. Aerospace America page at AIAA.org [aiaa.org]

Morphing wing technology tested before

[NathanielSamson]

I remember a few years ago seeing in Janes Defense Weekly and other publications about a F-111 testbed vehicle in which the forward edge was replaced with similar techology. While this experiment did not include the entire wing the technologies developed were a definite precursor to the technology presented in the artical. If anyone else remebers this plane please reply, it is possible I have the aircraft type wrong. In an end note I have to say very cool reapplication of sound technology. Who owns the right to the Wright Brothers IP, I see a juicy lawsuit coming. He He He

Re:Old stuff, new twist

[Chris Johnson]

"Out of this arbitrary arrangement, all stemming from the military client's refusal to have the engines in the body, the designers, groping for a formula that would reconcile structural integrity with aerodynamic balance, made their own luck. The first step was unorthodox. Instead of proposing a rigid wing, the structures men outlined a wing that would be unusually flexible, designed to bend with the aerodynamic stresses as it carried the loads of the underslung engines. This was called an 'aeroelastic' wing, an image that was, if anything, an understatement." -history of the design of the B-47 as reported in Clive Irving's "Wide-Body: The Making Of The Boeing 747

Sorry- I've lost patience with slashdotter smackdowns that have no justification. Dunno who you are, or whether you were having a bad day or what- points for not being an anonymous coward, anyway- but aeroelasticity dates back to the first jet bomber, the B-47, pattern for the later Boeing jet airliners, and it is precisely the word they used. No, I didn't design it: yes, I figured out that everything bends under stress and has elasticity many years ago, thank you.

Geez. Must be something in the water making Slashdotters cranky. Even I'm kinda cranky :D

AFTI F-111 did this in the 1980s

[labrat1123]

NASA was doing this in the 1980's with the AFTI F-111. They called it the MAW (mission adaptive wing). More info here http://www.dfrc.nasa.gov/DTRS/1992/PDF/H-1855.pdf and pics here http://www.dfrc.nasa.gov/gallery/photo/F-111AFTI/H TML/EC86-33385-002.html

Re:Test speeds.

[n9hmg]

supersonic speeds without at least passing through
You don't manoever while you're going trans-sonic. Generally, nobody does. The SR-71 climbs sonic, gets up to about mach 0.9, and power-dives in a straight line to about mach 1.1. It saves wear and tear on the airframe, AND it saves fuel. Supersonic fighter planes close and withdraw supersonic, do closing standoff attacks supersonic, but dogfight mostly subsonic.
They're going to manoever subsonic, straighten the control surfaces to slash through trans-sonic, and manoever again supersonic. Oh, and don't worry about the pilots yet. This is all windtunnel stuff so far. The model won't actually be able to turn, climb, and dive. It will be in a balance, measuring forces on it as it does its manoevers. Probably just a plain wing to start, later something plane-shaped.
Ever since I got to mess with the full-scale working model of the 1903 flyer at the Wilbur Wright birthplace in Millville, Indiana, I've thought that efficiency, especially in manoevering, would be enhanced by getting rid of transitions, if we could get sufficiently strong, rigid materials that wouldn't suffer from flexing.
At the very start, they chose the optimal configuration. The bishop's boys still rule!

Re:Alert Mr. Bernoulli!

[kaleth]

No. At subsonic speeds, the air flow around an airplane is considered to be incompressable (density is constant). Once you go supersonic, really weird stuff starts happening (like flows accelerating in a diverging nozzle) due to the fact that air then behaves as a compressible flow. Bernoulli's law is still valid at both points, we just don't usually think about the supersonic case.

Dryden Home page

[NoWhereMan]

The Dryden home page [nasa.gov] highlights this project. My last contract position was out there. Aside from some management issues (typical incompetent PHBs), there are a lot of smart engineers solving difficult problems there. It has been previously described as a geek playground. I still rank it as the best environment I ever worked in although the culture is slowly changing :(