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Funky Flying Wing Rotates 90 Degrees To Go Supersonic
Big Hairy Ian writes "An aircraft that resembles a four-point ninja star could go into supersonic mode by simply turning 90 degrees in midair. The unusual 'flying wing' concept has won $100,000 in NASA funding to trying becoming a reality for future passenger jet travel. The supersonic, bidirectional flying wing idea comes from a team headed by Ge-Chen Zha, an aerospace engineer at Florida State University. He said the fuel-efficient aircraft could reach supersonic speeds without the thunderclap sound (PDF) produced by a sonic boom — a major factor that previously limited where the supersonic Concorde passenger jet could fly over populated land masses."
You are not packing people right, please refer to http://www.ryanair.com for more information.
I was still kindof worried when the presentation started to compare the concept to a frisbee.
The article is nearly useless. Even bringing up scramjet testing in such an article is ridiculous namedropping, and anyone who has actually seen the X51 knows that is has nothing to do with this project except that neither will be flying in this planet in the current state of development.
There are so many questionable things about this concept, I can only assume that Mr. Zha has a second degree in grant writing or bullshittery to get and actual grant for research. And yet the linked presentation is, aside from some math simulation output data, poorer in content than at least half of the undergraduate senior projects in my Aero class back in the early 90s. One of the conclusions is "transition challenging, expected to be stable due to dual symmetric planform similar to flying Frisbee". Holy shit - that may very well be one of the most critical parts of the design. If you can't transition, you simply have a plane with the entire thrust force on a gimbal which can either be subsonic or supersonic. They other issue is the horrifically draggy airfoil shape required for subsonic flight due to the need to maintain symmetry in the supersonic mode. Their solution is either air injection into the flow and/or or slat deployment at speed to produce a proper lifting body - but that's an amazingly draggy way to accomplish such feat.
I wanted to like this - so much that I did read through the broken-english slides to see what novel concepts they discovered. Sadly, this is really a master's level, one or two semester examination of shock wave perceptibly reduction, and at some point somebody's non-technical room mate told them it looked more like an airplane if they flew it sideways.
Is it just my observation, or are there way too many stupid people in the world?
I think the most challenging part about this aircraft is vehicle dynamics. For stable flight the center of mass needs to be forward of the 1/4 chord section of the subsonic wing, and for supersonic flight it should be forward of the 1/2 chord section of the supersonic wing. That alone means this is plane is inherently unstable and flies like a leaf from a tree without software compensation. This doesn't begin to address the transition from subsonic to supersonic, where at some point you must have flow at 45 degrees over both supersonic and subsonic surfaces, stably; the plane would have a tendency to pitch and roll under this maneuver.
I am an aerospace engineer..