Supersonic Flying Wing?

I was looking through information on flying wing aircraft when I found a web page from Northrop Grumman. It talks about testing an usual supersonic varient of the Flying Wing. Now I'm only familiar with subsonic flying wings like the B-2 Spirit. Have a look at this:

EL SEGUNDO, Calif., March 23, 2006 -- Northrop Grumman Corporation (NYSE:NOC) has been selected by the U.S. Department of Defense to design the first-ever supersonic flying wing aircraft that can vary the sweep of its wing for the most efficient flight performance.


Illustrations accompanying this news release are available at: www.darpa.mil...

The Defense Advanced Research Projects Agency (DARPA) has awarded a contract to Northrop Grumman's Integrated Systems sector for the first phase of its Oblique Flying Wing (OFW) program, which aims to design and conduct flight tests of an experimental tailless, supersonic, variable-sweep flying wing. DARPA's goal is to demonstrate that such aircraft are feasible so that similar designs can be considered for future military missions.

Northrop's Supersonic Flying Wing

Reading this made me wonder if supersonic flight can be achieved with a fixed sweep version of the flying wing simular to the B-2 (Redesign for Supersonic flight of course!).

What do you all think, could a flying wing be made supersonic?

Tim

Mod Edit: Trimmed down large quote

[edit on 7/16/07 by FredT]

I don't know anything like the amount that kilcoo etc know about the science of aerodynamics but I would think that the change in the centre of pressure on an all-wing design as it passed through the sound barrier might prove a problem, I would also think that NASA/DARPA must have exhausted the possibilities of a fixed all-wing design if they are trying this. But like I said, I don't really know, this image below shows a variable sweep all-wing strategic bomber and SST design from many years ago that was schemed by Barnes Wallis (of the Dambusters bouncing bomb fame) just a few short years after the war.

The SST version is more like a tai8lless aircraft than a flying wing due to the concorde-like passenger cabin, but the bomber is all-wing except for the rearwards launching nuclear weapon.





[edit on 15-7-2007 by waynos]

Would that thing even fly without FBW? A Flying wing is one thing but that design looks even more unstable...

You are probably right Westpoint23.

The work is based on the aerodynamic theories of Robert T Jones.... for more info on Oblique Wing Theory, start here.....

en.wikipedia.org...

and here....

www.desktopaero.com...

NASA tested an oblique wing aircraft some years ago. It was on an aircraft called the Ames AD-1, which was purpose built by Burt Rutan for NASA. However, only low speed testing was done..... see here.....

www.fiddlersgreen.net...

Flight international reported quite some time ago that research in this field was being conducted by DARPA, so this is merely the announcement of the contract on behalf of DARPA, et al. see here .....

www.flightglobal.com...

There are further articles on this development and its connection with Northrop on the Flight International website.... search for 'Oblique Wing'

The Winged Wombat

[edit on 15/7/07 by The Winged Wombat]

Originally posted by waynos
I would think that the change in the centre of pressure on an all-wing design as it passed through the sound barrier might prove a problem, I would also think that NASA/DARPA must have exhausted the possibilities of a fixed all-wing design if they are trying this.

In a way that is what I suspected to begin with. Until I found this article, I had dismissed the idea of supersonic flying wings altogether. My issue of wonder origionally was the function of the elevons when being used as elevators. Back in the 1940's when supersonic research was first starting, they found that the shock wave from the wingss and fixed tail elevators was making the flap system ineffective which cause the planes to go out of control at Mach 1. It was because of this discovery that they started building supersonic aircraft with the "All-moving" horizontal tails.

Finding this article about NASA trying out a supersonic all-wing design has caused me to question my origional conclusions. I asked the question because I'm trying to redefine my understanding of supersonic aerodynamics based on this finding.

Tim

ATS member, "The Winged Wombat" called this one right.
The original article is in reference to the oblique flying wing project which is nothing like a B-2.

More information on this aircraft can be found by googling "oblique flying wing".

[edit on 7-15-2007 by intelgurl]

Originally posted by intelgurl
ATS member, "The Winged Wombat" called this one right.
The original article is in reference to the oblique flying wing project which is nothing like a B-2.

More information on this aircraft can be found by googling "oblique flying wing".

[edit on 7-15-2007 by intelgurl]

Ok, so this only works with the oblique flying wing, but not the regular b-2 type design. Thanks Natalie, that is what I was trying to figure out. You just confirmed what I suspected.

Tim

Originally posted by Ghost01
Reading this made me wonder if supersonic flight can be achieved with a fixed sweep version of the flying wing simular to the B-2 (Redesign for Supersonic flight of course!).

What do you all think, could a flying wing be made supersonic?

Yeah, sure it could be done.

Using technology similar to this:

www.nasa.gov...

NASA's Dryden Flight Research Center, Edwards, Calif., in cooperation with the U.S. Air Force Research Laboratory (AFRL) and Boeing Phantom Works, researched a high-tech adaptation of the Wright Brothers rudimentary "wing-warping" approach to aircraft flight control in the Active Aeroelastic Wing (AAW) flight research program. The focus of AAW research was on developing and validating the concept of aircraft roll control by twisting a flexible wing on a full-size aircraft. The test aircraft chosen for the AAW research is a modified F/A-18A obtained from the U.S. Navy in 1999.

The wing could be warped to keep the overall aero centre in-line with the centre of gravity. Also, since the pitch & roll control mechanism is warping the wing, aileron/elevator reversal (or boundary layer seperation upwind of aileron/elevators) is not an issue.


I'm not saying it would be easy - or even feasible at this point in time, but it definitely could be done.

Originally posted by kilcoo316
I'm not saying it would be easy - or even feasible at this point in time, but it definitely could be done.

Thanks! For the record, I never though of redesigning the B-2. I only wanted to know if it is possible with a fixed geometry flying wing aircraft like the B-2.

Personally, I don't even see a point in building a supersonic B-2.

Tim

In a time when technology allows almost anything to fly(F117 Night Hawk) getting a flying wing design into supersonic flight is mostly a matter of horsepower and computer power, but mostly horsepower. The surface drag and wind resistance on these types must be considerable with their cross section. The problems of supersonic flight controls were solved many years ago, and we have the high power engines required to do the job. The real question is can it be done while incorporating the stealth technology required for this aircraft to survive combat. Flying wings are very easy to spot both visually and on radar.

I am not particularly well versed on aerodynamics. However, I was always lead to believe that Supersonic aircraft must fit into a fairly long oval shape space in order to travel smoothly and effectively. Therefore I always believed that a flying wing would be both unstable and near impossible to get to hight speeds.

Jensy

Given enough thrust and provided that the object holds together you can propel anything to supersonic/hypersonic speeds. However there is a world of difference between that and stable/controlled "flying".

Yes a supersonic flying wing is possible.... just very hard. I understand lots about flying planes but I know nothing of the Supersonic regime or the technical names for everything.

First of all, the plane needs to fit inside the Mach cone.... right? If yes then, you'd most likely need a heavily swept wing.... to keep it stable you would probably do what the B-2 does; chuck airbrakes on the outer reaches of the wings with FBW to stabalise it. But as the wing is swept the span wouldn't be THAT long, and the outer regions of the wings (spoilers included) would be far back and not that far from the centreline.

That means that you're going to need loads of force on the spoilers to yaw the plane which would also slow the plane down from the drag.

In my opinion the only supersonic flying wing that would work well wouldn't even be a flying wing at all. More of a blended wing body with parts of the wings angled down?

[edit on 7-8-2007 by C0bzz]

Originally posted by C0bzz

In my opinion the only supersonic flying wing that would work well wouldn't even be a flying wing at all. More of a blended wing body with parts of the wings angled down?

[edit on 7-8-2007 by C0bzz]

So you're saying that, in spite of admitting that you don't know much about supersonics, that you disagree with the theories of the established and respected aerodynamicist Robert T Jones.

Hmmmmm

The Winged Wombat

Originally posted by The Winged Wombat

Originally posted by C0bzz

In my opinion the only supersonic flying wing that would work well wouldn't even be a flying wing at all. More of a blended wing body with parts of the wings angled down?

[edit on 7-8-2007 by C0bzz]

So you're saying that, in spite of admitting that you don't know much about supersonics, that you disagree with the theories of the established and respected aerodynamicist Robert T Jones.

Hmmmmm

The Winged Wombat

Point me to were I said that.

C0bzz,

Must I spell it out? OK, if I must....

Please go back to the beginning of this thread and read the links to tell you what the thread is all about - if you can't be bothered then I'll tell you - it's about Oblique Wing Theory and the contract awarded by DARPA to Northrop to build a demonstrator.

That theory was formulated by aerodynamicist Robert T Jones. The reason that this theory has not been fully investigated in the past is, no doubt, the problems associated with stability in all flight regimes, which can now (presumably - hopefully) be solved using computer activated flight controls.

So by saying that a supersonic flying wing would be .... something other than a flying wing.... you are stating that you disagree with Robert T Jones' theory, because he reckons it would look exactly like a flying wing, albeit flying at an angle to the airstream when supersonic!

All this in spite of the fact that you profess ignorance of supersonic aerodynamics!

To angle any part of the wing down (presumably for stability purposes) would be to induce drag from those quasi-vertical surfaces, which would be angled to the airstream at supersonic speeds - this would further complicate the algorithms required to overcome the control problems associated with the asymmetric chord / span relationship for a tapered wing operating at an angle to the airstream.

I can but conclude that you have not taken the time to peruse the theory or to have taken a glance at what the concept would look like.

The Winged Wombat


[edit on 8/8/07 by The Winged Wombat]

The Winged Wombat, lay off the insults, and two, read the thread:

Reading this made me wonder if supersonic flight can be achieved with a fixed sweep version of the flying wing simular to the B-2 (Redesign for Supersonic flight of course!).

What do you all think, could a flying wing be made supersonic?

Tim

Ok, so this only works with the oblique flying wing, but not the regular b-2 type design. Thanks Natalie, that is what I was trying to figure out. You just confirmed what I suspected.

Thanks! For the record, I never though of redesigning the B-2. I only wanted to know if it is possible with a fixed geometry flying wing aircraft like the B-2.

I have stated my opinion that a flying wing (like a B-2 not Oblique as he said) would be very hard to do.

I do not have the time nor energy to talk with people when they do not read the thread, they are insulting, and then they argue about my opinion when they clearly do not understand the slightest iota of the reasons behind my opinion.

Welcome to my ignore list.

[edit on 8-8-2007 by C0bzz]

I would suggest that if the control / stability problems of an oblique flying wing can be overcome, then to make a normal (ie:- not oblique) flying wing go supersonic would be child's-play!

And.... obviously you have no intention of learning anything, either.

For the benefit of all, it appears that C0bzz (conveyed by U2U to me) is insulted by me saying that he 'professes ignorance of supersonic aerodynamics' after he says 'I understand lots about flying planes but I know nothing of the Supersonic regime'

Not quite sure how that can be interpreted as an insult, unless he is insulted by those who believe him, or quote him, but what the hell.

I am more than happy to be on your ignore list, thank you.

The Winged Wombat


[edit on 8/8/07 by The Winged Wombat]