DARPA cancels Blackswift

Not many "black" programs have a website eh? With video no less

www.jsf.mil...



[edit on 10/13/08 by FredT]

reply to post by Zaphod58

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No the sonic boom is just as prevalent on any given day whether the speed is 650mph or 730mph... Depends on the barometric pressure. You are quite correct.

However, the ease at which the plane achieves that pressure overload depends on a number of factors, one of which being the speed at which an observer measures it.

eh, nevermind. I'm done here. I concede anything I didn't cover.

Hypersonic refers to Mach5 and above if you're talking to anyone in aviation. I don't think I've ever run across an alternative definition.

I'm not sure why you're talking about head- or tail-winds when we are discussing speeds in the several thousand miles per hour range.




As for the project, you could fund it (or pre-fund it) completely in the black for a variety of reasons. For example, if you thought the project was vital, and the next administration was likely to kill it.

Alternatively, you might fund an existing SAP on a shoe string or place it on life-support giving it just enough funding to keep the heart beating, but not enough to really proceed forward in the hopes of reviving it later in happier times or when it might be deemed vital.

Or you could just cut it.

I won't pretend to know which happened here, but I'm inclined to think that we're too close to the finish line with too much invested to kill it outright. But Waynos may be right, it may be sentimentality clouding my judgement.

As Waynos said, hypersonic is defined as Mach 5 by the ENTIRE AVIATION WORLD.

As for a sonic boom changing speeds, the only time it changes IS barometric pressure changes, but at lower altitudes it's not going to make a huge jump in the speed. It is much lower at higher altitudes where you have a much lower pressure. Wind speed has nothing to do with going supersonic. Wind speed does have lots to do with how soon you can get airborne, and at what speed though.

reply to post by FredT

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I never said that the F-35 is still black. Neh, it is a continuation, or spinoff, of the F-22 project, with public competitive funding. However, these things are brought to us from the black budgets.

Where are you getting that from? There is no way that the F-35 and F-22 would have come from the same place. They were never black. Even in the 1980s when they were doing the ATF designs the entire process was pretty transparent. The black budget is used for the Special Access Projects, which neither of these were.

Look, the entire crux of the issue, and I admit I am guilty of mencing words here, is that the speed of sound is quite frankly, measured by the velocity of sound itself. Obviously, when faced with a headwind, the breaking of said speed requires more energy as it must overcome the opposing "currents", if you will, of sound-movement.

The point is that when you are dealing with supposed speeds of "secret" military jets, it may be better, at this time, to deal with objects we KNOW exist and measure THEIR capabilities vs. their potential mission.

The F-22 and the F-35 are NEARLY the same jet!

Except that just by looking at the F-35 there IS a lot that we know about it. You can make a pretty good estimate of the top speed by the shape, and by the materials it's made out of. We know combat radius, we know weapons loadout...... We know a lot about it already.

reply to post by Zaphod58

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Pray tell, what would YOU guess, by looking at the F-35s shape is its potential TOP SPEED?!



[edit on 13-10-2008 by Jay-in-AR]

reply to post by Jay-in-AR

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PLEASE tell me you're not serious. My fiancee who knows that planes have two wings, and crash sometimes, and that's about it as far as her aviation skills go, can tell they're not even close to the same. Oh wait, they're both stealth, they have internal weapons bays, and they have two tails. Other than that they're not even close.

F-22:


F-35:


Ok, now show me how theyre almost the same plane. One uses 2D thrust vectoring, is a twin engine, and has four weapons bays. The other is a single engine, with minimal thrust vectoring if any, and dual weapons bays on the belly. One is an air superiority fighter, the other is a multirole tactical fighter/bomber.....

Please, point out how they're almost the same.

reply to post by Jay-in-AR

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You can't get an exact number for the top speed based on shape, but I'd say in the low Mach 2 range. It's too big, and has too much drag for much more than that. Certainly not in the Mach 3 or higher range, just by looking at the general shape.

If you look at the SR-71 it's obvious that it was built for speed. It has a very low head on silhouette, and the general shape just screams speed. The F-35 on the other hand is fairly bulky and has a lot of drag looking at it head on.

The only difference between the two of those planes is that the 35 is more broad-winged. Meaning, it can flare up with thrusters for vertical capability. Other than that, they have the same dimensions.

So how does that make them the same plane?

As to dimensions......

F-22:
Length: 62 feet 1 inch
Wingspan: 44 feet 6 inches
Height: 16 feet 5 inches

Speed: Mach 2 class

F-35:
Length:
A- 50 feet 5 inches
B- 50 feet 5 inches
C- 50 feet 8 inches

Wingspan:
A- 35 feet 0 inches
B- 35 feet 0 inches
C- 43 feet 0 inches
29.83 feet folded

Height:
A- 15 feet 0 inches
B- 15 feet 0 inches
C- 15 feet 5 inches

Max level speed at altitude: At least Mach 1.5

You're right! They're exactly the same! [/sarcasm]

You really beleive that?

F-22
Length 62.08 feet, 18.90 meters
Height 16.67 feet, 5.08 meters
Wingspan 44.5 feet, 13.56 meters
Wing Area 840 square feet
Horizontal Tailspan 29 feet, 8.84 meters

F-35
(specs for A,B,C)
Length 50.5-51.4 ft
Wingspan 35.0 ft (10.7 m) 35.0 ft (10.7 m) 43.0 ft (13.1 m)
Height 15.0 ft (4.6 m) 15.0 ft (4.6 m) 15.5 ft (4.7 m)
Wing Area 460 ft2 (42.7 m2) 460 ft2 (42.7 m2) 620-628 ft2 (57.6 m2)
MTOW 60000lbs


its not even close. The F-35 has a single engine as well.

Wow...22 and 35 the same jet? That's like saying F-18, and the F-16 are the same jet, they're completely different aircraft. I could list many MANY ways they are different. What makes you think they're the same? You've looked at the dimensions...what makes them the same plane..."nearly"?

reply to post by Shugo

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I think, think mind you that since they have two verticle stabilizers, internal weapons storage, and stealth they have to be the same???

"Nearly" being ratios to size. Go down the list, the dimensions ratio the same, with minor exceptions.

reply to post by FredT

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"That must be it"
Sarcasm much.

There are plenty of craft that somewhat resemble each other, doesn't make them the same aircraft. Anyone with a bit of aviation knowledge could tell you that.

Good info btw Zap/Fred, hopefully said poster will read the dimensions now.

reply to post by Jay-in-AR

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Nearly same dimensions does not make them the same plane. Don't you know anything about roles, payloads, and range?

[edit on 13.10.2008 by Shugo]