FALCON hypersonic development

Here is some good information about progress on the FALCON hypersonic technology development program:

Link


[Mod Edit: Link format - Jak]

[edit on 30/4/07 by JAK]

Hmm, the artical mentions wave rider designs in it as one of the key technologies involved in FALCON. I remember studing the shock wave rider concept a few years back when the "Aurora" stories were at their peek. the Idea is about using the shockwave generated by high speed flight to boost aerodynamic lift.

How well known/public is this program?

Was it always known?

If there were any "secret" components to FALCON, could that explain any of the sonic booms that people thought were Aurora?

Tim

Originally posted by Ghost01
How well known/public is this program?

Was it always known?

It was publicly announced from the beginning, and the overall status has been and still is publicly known.

If there were any "secret" components to FALCON, could that explain any of the sonic booms that people thought were Aurora?

The "Aurora" hype was mainly in the first half of the 1990s. The earliest roots of FALCON can be traced back to ~1998, and FALCON itself was formally established in late 2002. Anyway, FALCON is not a "black" program. Any Special Access Program related to hypersonic research would by definition not be a part of FALCON.

By the way, the sheer number of ongoing non-"black" hypersonic research programs (e.g. FALCON, X-51, HyFly) is a very strong argument against all the rumours about operational hypersonic aircraft (let alone aerospaceplanes!) allegedly used by the USAF.

Regards
yf

Thanks YF!

I though that was the case, but I wanted to ask just be sure. It was kind of thinking out loud. Take care buddy!

Tim

The wave rider study has been knowen for sometime now. I remeber reading about it as well about 3 years back. Its a neat idea that if it pans out could see some pretty amazing things out of.

Originally posted by Canada_EH
The wave rider study has been knowen for sometime now. I remeber reading about it as well about 3 years back. Its a neat idea that if it pans out could see some pretty amazing things out of.

Its been around longer than you think Canada EH ! I remember seeing an illustration of a future waverider design (imagine a basically banana shaped Concorde with droopy wings) in an aircraft book when I was 8. I am now 42. (I shouldn't have admitted that last bit, should I)

[edit on 30-4-2007 by waynos]

Originally posted by waynos

Originally posted by Canada_EH
The wave rider study has been knowen for sometime now.

I remember seeing an illustration of a future waverider design (imagine a basically banana shaped Concorde with droopy wings) in an aircraft book when I was 8. I am now 42.

(I shouldn't have admitted that last bit, should I)

Haha a banana Concorde waverider those 3 words start me on some pretty funny mental pictures that if I had time I'm sure I would post oh here lol.

Oh and Yesssss after 4 years of ATS for myself I've finally got waynos to slip his actual age! It feels sweet and you should at the least be embarassed since most people here should respect age not poke fun at it eh?

Originally posted by Canada_EH
Haha a banana Concorde waverider those 3 words start me on some pretty funny mental pictures that if I had time I'm sure I would post oh here lol.

Is there something you find paticularly Apealing (or is that apeeling)about a giant banana?

While not a wave rider, this will be the second banana-shaped aircraft ever flown. The first was the US Army's Chinook helicopter, which was famous for it use in Vietnam. My biggest question is how do you build a wave rider shaped like that?

Usually a wave rider is a flatter aircraft design.

Tim

I'm afraid it's older than that guys, didn't the XB-70 Valkyrie bomber work on a similar concept? I recall reading something about it's wings being angled down during high speeds to achieve lift from compressed air funneled via the engine design.

Yes, that used the principle which I think was first proposed for aircraft design in the 1950's, the concept I saw was a 'pure waverider' and my previous description was so vague that at least one of you seems to be imagining it upside down

I have attempted a quick sketch of the design I saw, shown below, and although it left a lasting impression on me, bear in mind this was over 30 years ago!! Anyhow, this is basically how I remember it, and it was supposed to be for a 300 seat transport.

Originally posted by WestPoint23
I'm afraid it's older than that guys, didn't the XB-70 Valkyrie bomber work on a similar concept? I recall reading something about it's wings being angled down during high speeds to achieve lift from compressed air funneled via the engine design.

It was one of the first planes to truely use the shockwave from what I can remeber it recovered 30% lift with no extra drag. Infact desided to pull some info from wikipedia so take it with a grain of salt eh. Also with the wing tips angled the full 65 degrees it had the added bonus of increasing the aircraft's directional stability at supersonic speeds

The Valkyrie was configured as a canard delta wing, and built largely of stainless steel, honeycomb sandwich panels, and titanium. It was designed to make use of a phenomenon called "compression lift", achieved when the shock wave generated by the airplane flying at supersonic speeds is trapped underneath the wings, supporting part of the airplane's weight. Under the center of the wing, the Valkyrie featured a prominent wedge at the center of the engine inlets, designed to produce a strong shock wave. By acting upwards upon the wings, this shock wave would allow the aircraft to recover energy from its own wake. At high speeds, compression lift increased the lift of the wings by thirty percent, with no increase in drag.

en.wikipedia.org...

[edit on 22/08/06 by Canada_EH]

did my drawing kill the thread

Has anyone seen waverider concepts like this? I was curious about the blunt trailing edge, but I suppose its no different in that respect to the X-15.

Waynos:
what's defferent between scramjet and ramjet

[edit on 31-5-2007 by emile]

[edit on 31-5-2007 by emile]

Sorry, I think scram-ram-jet is same, this poet to be rubbish

[edit on 31-5-2007 by emile]

No, they are not the same emile, a ramjet only works at high speed because it needs to high velocity of inrushing air, ramjet powered aircraft have to be air dropped by something else or need a second engine to take them to the speeds where the ramjet operates. A scramjet negates this need as it can operate at all speeds.

This is as simple as I can make it and misses out quite a bit.

Originally posted by WestPoint23
I'm afraid it's older than that guys, didn't the XB-70 Valkyrie bomber work on a similar concept? I recall reading something about it's wings being angled down during high speeds to achieve lift from compressed air funneled via the engine design.

No, I'm afraid not.


While that idea was explored, it was not used.


The wingtips were angled down to compensate for the move in aerodynamic centre going from subsonic to supersonic flight.


Compression lift (in the sense talked about here) was not used in the XB-70 design that was flown. The wingtips do act as endplates/winglets to a degree, reducing the lift-induced vortices, but the reduction in aspect ratio from bending the wingtips would offset this (probably even dominate over it to be honest).



edit: The increase in vertical surface area also played a large part in lateral stability.

[edit on 31/5/07 by kilcoo316]

[edit on 31/5/07 by kilcoo316]

Originally posted by kilcoo316

Originally posted by WestPoint23
I recall reading something about it's wings being angled down during high speeds to achieve lift from compressed air funneled via the engine design.

While that idea was explored, it was not used.

The wingtips were angled down to compensate for the move in aerodynamic centre going from subsonic to supersonic flight.

You mention the point about lateral stablity that I also mentioned early. My question is about how you know that the compression lift that was generated by the Val wasn't a large amount? In my research it has said that the plane could of (did?) benifited from the compression by 30% increase in lift therefore using less power to retain their flight altitude.

[edit on 22/08/06 by Canada_EH]

Originally posted by Canada_EH
You mention the point about lateral stablity that I also mentioned early. My question is about how you know that the compression lift that was generated by the Val wasn't a large amount? In my research it has said that the plane could of (did?) benifited from the compression by 30% increase in lift therefore using less power to retain their flight altitude.

[edit on 22/08/06 by Canada_EH]

By bending the wingtips down, they were moved out of the Mach cone of the engine inlets - this is where considerable drag savings were made.


Compression lift doesn't really kick in to Mach 5+ IIRC. The 30% figures quoted around the net are rubbish.


edit: Consider it - do you think Lockheed would have turned down a L/D increase of 30% if all they needed was to put variable wingtips on the blackbird? Your damn right they wouldn't.

[edit on 31/5/07 by kilcoo316]

Originally posted by kilcoo316
edit: Consider it - do you think Lockheed would have turned down a L/D increase of 30% if all they needed was to put variable wingtips on the blackbird? Your damn right they wouldn't.

The Blackbird was a totally different design, the fuselage, the engine placing etc... so no just bending the wingtips would not have done anything. The XB-70 on the other hand may have been designed with compression life in mind...

Originally posted by WestPoint23
The Blackbird was a totally different design, the fuselage, the engine placing etc... so no just bending the wingtips would not have done anything. The XB-70 on the other hand may have been designed with compression life in mind...

Yes, and do you think it would have been designed the way it was if there was a 30% swing in L/D on offer with compression lift?


Not a snowballs chance in hell.