Posted on 01/03/2010 7:28:32 PM PST by ErnstStavroBlofeld
For some time, NASA has focused much of its limited aeronautics research budget on the blended wing-body configuration, believing it has the best chance of meeting its aggressive environmental targets for commercial aircraft entering development after 2025. These include reductions exceeding 70% in fuel burn, 75% in emissions and 71dB in airport noise compared to today's airliners.
Now the agency is broadening its search to include other alternatives to the ubiquitous tube-and-wing layout. And one of those is the truss-braced wing (TBW), or strut-braced wing (SBW), a concept that allows a substantially longer span for significantly higher lift-to-drag (L/D) ratio. It will come as no surprise that this is not a new concept. France's Hurel Dubois used a truss to brace the slender, high aspect-ratio wing of its HD.31 short-haul airliner, first flown in 1953.The truss, or simpler single-member strut, supports the wing and allows it to be longer and thinner for lower drag. Increasing the aspect ratio (square of wing span divided by area) reduces lift-induced drag, while reducing aerofoil thickness-to-chord ratio promotes low-drag laminar flow. The trick is to mazimize L/D while minimizing the weight and drag penalties of the truss structure.
Werner Pfenninger developed the TBW concept at Northrop while working to perfect the laminar flow wing. He designed the X-21A, which first flew in 1963 and demonstrated active laminar flow control via boundary-layer suction through slots in the wing, Pfenninger later joined NASA where in 1975, working with Lockheed, he produced this extraordinary concept based on the C-5 Galaxy transport
(Excerpt) Read more at aviationweek.com ...
I like the forward swept wing. Maybe there is room for both
Its the return of the Biplane!!
Just add the observation platform so wing walkers can return.
NASA chose the Space Shuttle as the best means of getting into space.
NASA promotes Global Warming as our future climate.
It’s my guess that Braced Wings fall in the same catagory.
What’s next? Non retractable landing gear and propellers?
Open cockpits. Canopy bubbles disrupt the flow of air, you know.
LMAO you guys are a riot.
The concept is simple enough. A triangular structure is incredibly strong. Add another brace to make a triangular shape out of the wing, the fuselage, and this new structure. But wait, while this lets you build a lighter wing, now you have the drag of this new structure. Ahh, wait, put an airfoil on this new structure and it can produce lift as well. But wait, aircraft wings are incredibly strong through the concept of bend but don't break (Don't understand that comment? On your next airline flight, sit at the overwing exit and watch what happens to the wing during takeoff). OK, we'll tune the structure of the wing and the new surface until they both deflect the same amount under the same load. But wait, they're joined together so when they flex in one direction, one has to be longer than the other....
It goes on and on like this until only one conclusion can be reached. Aircraft are shaped they way they are because after a little more than a hundred years of refinement, that's the best shape there is. Until we can go outside of the atmosphere, aircraft aren't going to look a whole lot different than they do today. A few small tweaks, but nothing wholesale will change.
... but here we go, GE and NASA to Revive Open Rotor Jet Engines
Heh ... "The only real drawback to using a Propfan engine was the noise that was present inside the cabin. "
As Carson used to say, "How loud is it?"
Wheel pants!
Shall we apply your technological wisdom to televisions, computers and space travel?
You are an idiot.
I think that the new designs are very neat. The military applications are limitless.
Ok, I’m starting to get some ideas...
http://en.wikipedia.org/wiki/File:Rutan_quickie_q2.jpg
Start with the above plane. But make the upper wing and the lower wing angle towards eachother until they meet about 10-15’ from centerline. Then from that point, a single wing extends another 10’ ish out.
So the upper wing will be foward swept to the joining point, and the lower wing will be rear swept to the joining point. The upper wing will have a negative dihedral, and the lower wing a positive dihedral.
Yeah, I think I’d like the way it would look. Not so sure about how it would work though.
The Russians seem to think so. How about forward-swept wings on the F-15, with canards and thrust vectoring. Think the maneuverability on such a ship could extend service life as a 4th Generation air superiority fighter?
Jesus what did they do, detract money from important global warming research?
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.
