Forum: X-planes

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Thank you, habu2... Smile

But, what happened with the Valkyrie...? (I don't know much about it...)

Two B-70s were built. One, AV2, crashed in the desert on June 8, 1966 after participating in a "General Electric" photo shoot. Several GE powered planes got in formation to take pictures and a F-104 rolled over the top of the B-70, killing the pilot of the Starfighter and causing the B-70 to spin. The pilot survived but the co-pilot did not.

AV1 was retired to Dayton, Ohio for the Air Force Museum in February of 1969. It is still there, by the way.

The B-70 was designed to study the effect of compresion lift at high speeds, and as such had wingtips that folded down. The B-70 incorporated 6 YJ-93 turbojets, a derivative of the J-79 core.

The Soviet Union developed the MiG-25 to counter this threat, even though the B-70 program was canceled.

I am sure there is lots more but that was all from memory.

Last edited by RyanCollins on Nov 19, 2004 - 11:31 PM; edited 2 times in total

This is what I founnd about the specifications of XB-70

North America XB-70 "Valkyrie"

Specifications:
Span: 105 ft.
Length: 185 ft. 10 in. without boom; 192 ft. 2 in. with boom
Height: 30 ft. 9 in.
Weight: 534,700 lbs. loaded
Armament: None
Engines: Six General Electric YJ-93s of 30,000 lbs. thrust each with afterburner.

Performance:
Maximum speed: 2,056 mph. (Mach 3.1) at 73,000 ft.
Cruising speed: 2,000 mph. (Mach 3.0) at 72,000 ft.
Range: 4,288 miles
Service Ceiling: 77,350 ft.

I got this pictures of the "front view of the XB-70 with all three wingtip angles":

My pics of AV-1 at WP USAF Museum are here

The XB-70 program was really killed by the development of the ICBM, in addition to being way over budget and the fallout from the crash/loss of AV-2.

Also, the latest Soviet SAM (I believe SA-2) was another factor that led to the B-70's cancellation. I have heard that the program was actually cancelled before the midair, which by the way killed test pilot Joe Walker. Walker was the chief test pilot in the X-15 program after Scott Crossfield left the program. The Valkyrie was/is a beautiful jet though, still one of the best looking planes ever built, in my opinion.

Beers and MiGs were made to be pounded!

Just to get something straight, the XB-70 was an X-plane, experimental not an operational bomber?
Just to be sure

Not officially one of the research "X-Planes", the X prefix did denote prototype/experimental though. NASA later used AV-1 as a research aircraft, but it was never one of the "X Planes" like the X-1, X-15 etc.

Did the XB-70 and TSR.2 have the ability to aerial refuel?

I don't know about the TSR.2 but the neither of the two XB-70s had provisions for inflight refueling. The third XB-70 was to have a refueling receptacle forward of the windscreen and was to test supersonic refueling, but the program was canceled before #3 was built.

TSR.2 had a retractable IFR probe on the left of the forward fuselage.

http://www.vectorsite.net/avtsr2.html A good TSR.2 page.

Habu2,
If the XB-70 was to test supersonic refueling, what were they planning to use for a tanker?

johnwill wrote:

Habu2,
If the XB-70 was to test supersonic refueling, what were they planning to use for a tanker?

The books I have didn't say, but they assumed it would be another XB-70 (KB-70?)

IMO the best XB-70 book is "Valkyrie" by Dennis Jenkins and Tony Landis, highly recommended for Valkyrie fans.

The XB-70 was capable of cruising at Mach 3. It was powered by six YJ93 turbojets, which impresses me. Unlike the SR-71, which used the unique J58 engines which combined aspects of the turbojet and the ramjet, the YJ93 was a raw turbojet.

Classically, one is told that simple turbojets do not do well at Mach 3 and can even be destroyed by such speeds. What special design implementations were there in the YJ93 that allowed it to do what other turbojets could not?

If a Mach 3 turbojet could be designed in 1960's, then why haven't we seen more Mach 3 turbojet designs in more recent years? Surely we would be able to design engines with such capabilities with even greater efficiency than the YJ93?

What are the drawbacks to Mach 3 turbojets? High costs? Long maintenance times? Poor performance at low altitudes and low airspeeds? Large size?

Fuel flow sucks, and long term health due to the high temps are also lousy

Forum: X-planes

XB-70 Valkyrie