XB-70 Valkyrie

Unread postPosted: 19 Nov 2004, 22:11
by habu2

Unread postPosted: 19 Nov 2004, 22:12
by RyanCollins
Thank you, habu2... :)

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

Unread postPosted: 19 Nov 2004, 22:24
by Occamsrasr
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.

Unread postPosted: 19 Nov 2004, 23:21
by RyanCollins
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":

Unread postPosted: 20 Nov 2004, 01:19
by habu2
My pics of AV-1 at WP USAF Museum are here

Image

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.

Unread postPosted: 21 Nov 2004, 02:34
by TC
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!

Unread postPosted: 21 Nov 2004, 09:15
by KarimAbdoun
Just to get something straight, the XB-70 was an X-plane, experimental not an operational bomber?
Just to be sure

Unread postPosted: 21 Nov 2004, 19:59
by habu2
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.

Midair refuel TSR.2 and XB-70

Unread postPosted: 23 Jul 2007, 19:02
by bdn12
Did the XB-70 and TSR.2 have the ability to aerial refuel?

RE: Midair refuel TSR.2 and XB-70

Unread postPosted: 24 Jul 2007, 04:03
by habu2
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.

RE: Midair refuel TSR.2 and XB-70

Unread postPosted: 24 Jul 2007, 08:30
by snypa777
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.

RE: Midair refuel TSR.2 and XB-70

Unread postPosted: 24 Jul 2007, 13:30
by johnwill
Habu2,
If the XB-70 was to test supersonic refueling, what were they planning to use for a tanker?

Re: RE: Midair refuel TSR.2 and XB-70

Unread postPosted: 25 Jul 2007, 02:45
by habu2
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 and the YJ93.

Unread postPosted: 03 Nov 2008, 22:20
by Kryptid
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?

RE: The XB-70 and the YJ93.

Unread postPosted: 04 Nov 2008, 01:35
by Roscoe
Fuel flow sucks, and long term health due to the high temps are also lousy

RE: The XB-70 and the YJ93.

Unread postPosted: 04 Nov 2008, 03:51
by Habu
The J-58 was NOT a ramjet at all. It had ramjet-like qualities, because of the six bypass tubes that would take air from P4 and reroute straight to the afterburner. When at speed, the regular part of the engine still operated as a normal turbojet. The main thrust however, came from the inlets and its differential pressure.

RE: The XB-70 and the YJ93.

Unread postPosted: 04 Nov 2008, 04:41
by TC
I'd have to ask two questions:

1) Why have a turbojet when you could have a turbofan?

Turbofans are much more efficient, both with fuel flow and operating temps

2) Do we need to go Mach 3?

I'd have to say no. Speed may be life, but L-O technology puts the crew at even less risk. Let me put it this way: Why dash away from a hostile threat at Ludicrous Speed, when you can ingress and egress the threat area without the threat knowing you were there?

The Concorde and Tu-144 proved what an inefficient waste SSTs were, and we also were able to trade the BONE's Mach 2 speed for lower RCS capabilities, while still retaining the ability to achieve Mach 1. No BONEs lost as of this writing, due to hostile fire, so I'd say that Rockwell got it right.

Unread postPosted: 04 Nov 2008, 05:22
by Occamsrasr
Someone who knows more about the GE engines can correct me but I think the B-70 was first designed with a boron burning version of the J93 in mind. Something like the J93-GE-5. That engine was to be rated at 33,000 pounds of thrust. They ended up using a more conventional non-zip fuel like JP-6 in the J93-GE-3 version of the engine and got about 30,000 pounds of thrust.

While the B-70 could hit Mach 3 for periods at a time I can't remember if it ever went one full hour at that speed, so I am not sure that it really could cruise at Mach 3 like the SR-71 did.

I can still remember as a little kid seeing air vehicle #2 being flown in on its last flight to Wright-Patterson for the museum.

Re: RE: The XB-70 and the YJ93.

Unread postPosted: 04 Nov 2008, 05:34
by Habu
TC wrote:No BONEs lost as of this writing, due to hostile fire, so I'd say that Rockwell got it right.


Well, that's assuming they can even get a sortie off. They didn't get it that right ;)

Re: RE: The XB-70 and the YJ93.

Unread postPosted: 04 Nov 2008, 05:39
by TC
Habu wrote:Well, that's assuming they can even get a sortie off.


Yes, but when they FINALLY do... :lol:

...and they have a much better mission capable rate than the Blackjack. But I think we beat this horse to death in another thread. :wink:

RE: Re: RE: The XB-70 and the YJ93.

Unread postPosted: 04 Nov 2008, 05:43
by Habu
Yeah, I know, I just couldn't resist. :-D

But anyway, yeah I'm with ya, L-O is the way to go. I think it's been proven that higher-faster-farther doesn't work anymore.

RE: Re: RE: The XB-70 and the YJ93.

Unread postPosted: 04 Nov 2008, 17:46
by TC
You got it. :thumb:

The B-70 was a very over-ambitious project, especially when considering the, at-the-time, future world events involving the U.S. Would the B-70 have been a viable weapon system in Vietnam? No way, and most especially not after the bombing halt up North.

The BUFF was easily converted from a nuclear strike platform to a conventional role. It would not have been anywhere near that easy with the Valkyrie.

Even if the AF had attempted to utilize the Valkyrie in a conventional manner, they'd have to slow down to an appropriate attack speed, which would have left them vulnerable to SAMs, and possibly high altitude airburst AAA.

Too fast, like its Mach 3 cruise speed, and they'd have run the risk of flying into China before being able to turn around.

I think cancelling the Valkyrie was one decision that McNamara got right. It was wrong for its time, and its cancellation eventually led to the BONE, which is a much more practical weapon system.

Unread postPosted: 06 Nov 2008, 04:32
by sferrin
Occamsrasr wrote:While the B-70 could hit Mach 3 for periods at a time I can't remember if it ever went one full hour at that speed, so I am not sure that it really could cruise at Mach 3 like the SR-71 did.


Kind of a silly reason. It flew at Mach 3 for 32 minutes. That was the amount of time required for a full heat soak and everything was fine so they ended the flight.

Unread postPosted: 06 Nov 2008, 08:53
by Prinz_Eugn
sferrin wrote:
Occamsrasr wrote:While the B-70 could hit Mach 3 for periods at a time I can't remember if it ever went one full hour at that speed, so I am not sure that it really could cruise at Mach 3 like the SR-71 did.


Kind of a silly reason. It flew at Mach 3 for 32 minutes. That was the amount of time required for a full heat soak and everything was fine so they ended the flight.


I thought I remember it being longer than that, sure that wasn't just the first cruise test?

Unread postPosted: 07 Nov 2008, 19:55
by sferrin
Prinz_Eugn wrote:
sferrin wrote:
Occamsrasr wrote:While the B-70 could hit Mach 3 for periods at a time I can't remember if it ever went one full hour at that speed, so I am not sure that it really could cruise at Mach 3 like the SR-71 did.


Kind of a silly reason. It flew at Mach 3 for 32 minutes. That was the amount of time required for a full heat soak and everything was fine so they ended the flight.


I thought I remember it being longer than that, sure that wasn't just the first cruise test?


Several flights flew supersonic for an hour or two but the longest Mach 3 stretch was 32 minutes. Jenkins' Valkyrie book breaks down each flight of both XB-70s. One 2+ hr flight included testing engine air starts- at Mach 2.4. :shock:

Re: RE: The XB-70 and the YJ93.

Unread postPosted: 07 Nov 2008, 21:50
by JpoLgr
TC wrote:...and they have a much better mission capable rate than the Blackjack. But I think we beat this horse to death in another thread. :wink:


Cheers TC! :D
John.

RE: Re: RE: The XB-70 and the YJ93.

Unread postPosted: 07 Nov 2008, 23:13
by TC
This Bud's For You John Boy! :beer:

Yeah, the B-70 was no doubt a good looking jet. Definitely in the top 4 for American strategic bombers as far as looks go. In no particular order, I'd say the dark gray BONEs, the Valkyrie, the Hustler, and the B-47...or maybe EXACTLY in that order.

However, looks don't hack it, compared to practicality...and as I said, Vietnam would have rendered the Valkyrie virtually useless. It wasn't made for that type of war, and had we purchased enough Valkyries to equip just a couple of Bomb Wings, people would have questioned their cost, need, and usefulness, when they would have sat out of the war for just that reason.

Hmmm...sounds a helluva lot like another bomber that I'm a big fan of. :wink:

TEG? Tap, tap, tap..... TEG?

Unread postPosted: 08 Nov 2008, 04:20
by Gums
Salute!

Habu KNOWS about the Oxcart. So does Parrot-breath.

TEG (that engine guy) REALLY KNOWS!!!!!

We've gone thru this before and even posted the tech manuals and diagrams for the J-58. It had bypass ducts because it didn't need or could not use all that air at high mach numbers.

The neatest thing about the B-70 was the "shock rider" concept. I truly believe it would have done just fine in production, but requirements changed and we had a new administration and ........

Gums sends ...

Unread postPosted: 08 Nov 2008, 09:15
by ford2go
I'm not up on the tech stuff, but I lived through the era.

There was a lot of pressure from the airlines to get the gov't to develop a supersonic aircraft. Everybody thought that the quick transatlantic flights would be a money machine. But, they wanted the government to fund the research.

Also, I think that there was the usual intenational competition for bragging rights.

The French won that one, but of course, it didn't matter in the end. Probably restricting US landing sites to avoid sonic booms didn't help ( I know that this happened early on, and I never heard that the restriction was removed)

Re: RE: Re: RE: The XB-70 and the YJ93.

Unread postPosted: 08 Nov 2008, 17:26
by sferrin
TC wrote:Vietnam would have rendered the Valkyrie virtually useless.


How so? Did it render ICBMs useless? We'd have still had the B-52s around to drop conventional bombs (don't know how accurate they could be dropped dumb from mach 3 and 80,000 feet though). And if the B-70s had managed to last to today (not impossible as we'd have babied those suckers) they'd be just the ticket for dropping deep penetration weapons.

Re: RE: Re: RE: The XB-70 and the YJ93.

Unread postPosted: 08 Nov 2008, 22:48
by TC
sferrin wrote:How so? Did it render ICBMs useless?


We didn't utilize any ICBMs in Vietnam, though. We did, however, utilize more than one aircraft, which had originally been designed to be nuke-capable in a conventional role. The Thud and the BUFF are prime examples.

sferrin wrote:We'd have still had the B-52s around to drop conventional bombs (don't know how accurate they could be dropped dumb from mach 3 and 80,000 feet though).


Exactly my point. Vietnam was entirely the wrong type of war for the B-70. Conventional munitions dropped at Mach 3 from 80K is a non-option.

On the flip side of the coin, slowing down, and descending to salvo drop GP munitions, ala, the BUFF, would have been suicide for a Valkyrie crew. No way that it could've done that type job, and survived the SAMs and/or AAA.

Also, as I said before, had we bought enough B-70s to equip a couple of Bomb Wings, politicians in Washington would have been in an uproar over the expense of the bombers, coupled with their non-use in Vietnam.

Another example of this, is the B-58. It never fired a shot in anger, and it too did not make it past the Vietnam era, being retired in January of 1970.

Re: TEG? Tap, tap, tap..... TEG?

Unread postPosted: 09 Nov 2008, 01:55
by That_Engine_Guy
Gums wrote:Salute!

Habu KNOWS about the Oxcart. So does Parrot-breath.

TEG (that engine guy) REALLY KNOWS!!!!!


Thanks Gums :cheers:

Just the motor stuff... Yes the J58 could "cruise" at MACH3 all day long given the proper amount of fuel.

If you've ever seen "Blackbird the Movie" made by LM back in the late 80's early 90's just before the program was dropped; you'll notice the pilot retard the throttles when reaching MACH 3 on the meter.

Yes I said RETARD the throttles when reaching MACH 3.

I wouldn't want to violate that "99 year disclosure clause" but I can say the Blackbird (J58) was capable of the "plus" speeds it is often quoted to have.

Besides, J58s look very beautiful with their gold-plated tubing and such.

Point here, to go fast costs big $$, and today it's not about fast, it's about cheap.

Keep 'em flyin' :thumb:
TEG

RE: Re: TEG? Tap, tap, tap..... TEG?

Unread postPosted: 09 Nov 2008, 03:44
by johnwill
There may be others on display elsewhere, but I visited the Evergreen Aviation Museum at McMinnville, OR last month and enjoyed seeing the J-58 on display. A beautiful piece of machinery.

Re: TEG? Tap, tap, tap..... TEG?

Unread postPosted: 09 Nov 2008, 04:52
by TC
That_Engine_Guy wrote:Yes I said RETARD the throttles when reaching MACH 3.


:lol: Uh...he said RETARD Beavis. :lol:

That_Engine_Guy wrote:I wouldn't want to violate that "99 year disclosure clause" but I can say the Blackbird (J58) was capable of the "plus" speeds it is often quoted to have.


Forgive me if I plead ignorance TEG, but I honestly didn't know that you had been a J58 troop. Cool stuff!

Yeah, the best story I had ever heard about the "plus" in Mach 3+ was from Brian Shul, when he was talking about making feet wet from the coast of Libya, following OEDC. He said, "The Mach meter was reading off numbers we had never seen before!" :shock:

Re: RE: Re: RE: The XB-70 and the YJ93.

Unread postPosted: 09 Nov 2008, 16:49
by sferrin
TC wrote:
sferrin wrote:How so? Did it render ICBMs useless?


We didn't utilize any ICBMs in Vietnam, though. We did, however, utilize more than one aircraft, which had originally been designed to be nuke-capable in a conventional role. The Thud and the BUFF are prime examples.


Exactly. We wouldn't have HAD to use the B-70s in Vietnam. Just like we didn't use B-58s or F-106s.




TC wrote:Another example of this, is the B-58. It never fired a shot in anger, and it too did not make it past the Vietnam era, being retired in January of 1970.



That had more to do with it's relatively low bang for the buck. The B-70 would have been much more capable.

Re: TEG? Tap, tap, tap..... TEG?

Unread postPosted: 09 Nov 2008, 16:52
by sferrin
That_Engine_Guy wrote:
Gums wrote:Salute!

Habu KNOWS about the Oxcart. So does Parrot-breath.

TEG (that engine guy) REALLY KNOWS!!!!!


Thanks Gums :cheers:

Just the motor stuff... Yes the J58 could "cruise" at MACH3 all day long given the proper amount of fuel.

If you've ever seen "Blackbird the Movie" made by LM back in the late 80's early 90's just before the program was dropped; you'll notice the pilot retard the throttles when reaching MACH 3 on the meter.

Yes I said RETARD the throttles when reaching MACH 3.

I wouldn't want to violate that "99 year disclosure clause" but I can say the Blackbird (J58) was capable of the "plus" speeds it is often quoted to have.

Besides, J58s look very beautiful with their gold-plated tubing and such.

Point here, to go fast costs big $$, and today it's not about fast, it's about cheap.

Keep 'em flyin' :thumb:
TEG


The original A-12 configuration would have went Mach 3.8 with them. :shock: (Not the A-12 as produced, although it did reach Mach 3.6 in tests according to some sources.)

Re: RE: Re: RE: The XB-70 and the YJ93.

Unread postPosted: 09 Nov 2008, 23:11
by TC
sferrin wrote:The B-70 would have been much more capable.


I assume you mean more capable in its intended mission. The Valkyrie would've been perfect for laying in a nuke on the Kremlin, but not for bombing "suspected truck parks" on the Ho Chi Minh Trail.

RE: Re: RE: Re: RE: The XB-70 and the YJ93.

Unread postPosted: 10 Nov 2008, 03:07
by parrothead
Call me crazy (you wouldn't be the first one), but wouldn't a bomber version of the Blackbird be pretty cool with nukes? I mean, what's going to kill it?

Re: RE: Re: RE: Re: RE: The XB-70 and the YJ93.

Unread postPosted: 10 Nov 2008, 03:17
by TC
parrothead wrote:I mean, what's going to kill it?


Congress. They only people in the world who can claim Blackbird kills.

Oh, wait! You meant what sort of threats would it have faced? :lol:

Re: TEG? Tap, tap, tap..... TEG?

Unread postPosted: 10 Nov 2008, 06:38
by Habu
Gums wrote:Salute!

Habu KNOWS about the Oxcart. So does Parrot-breath.

TEG (that engine guy) REALLY KNOWS!!!!!

We've gone thru this before and even posted the tech manuals and diagrams for the J-58. It had bypass ducts because it didn't need or could not use all that air at high mach numbers.

The neatest thing about the B-70 was the "shock rider" concept. I truly believe it would have done just fine in production, but requirements changed and we had a new administration and ........

Gums sends ...


Haha! Thanks Gums! I do remember those old threads. Good times...good times...

Re: RE: Re: RE: Re: RE: The XB-70 and the YJ93.

Unread postPosted: 10 Nov 2008, 06:39
by Habu
parrothead wrote:Call me crazy (you wouldn't be the first one), but wouldn't a bomber version of the Blackbird be pretty cool with nukes? I mean, what's going to kill it?


There was one proposed! But the XB-70 project was in the works at the time.

RE: Re: RE: Re: RE: Re: RE: The XB-70 and the YJ93.

Unread postPosted: 10 Nov 2008, 06:50
by Guysmiley
I seem to recall that the SR-71/A-12 was limited by maximum compressor inlet temperature.

Re: RE: Re: RE: Re: RE: Re: RE: The XB-70 and the YJ93.

Unread postPosted: 10 Nov 2008, 06:55
by Habu
Guysmiley wrote:I seem to recall that the SR-71/A-12 was limited by maximum compressor inlet temperature.

Limited as to what? If you meant top speed, then yes. 427 max CIT. After that , the J58 would have started destroying itself.

Re: RE: Re: RE: Re: RE: Re: RE: The XB-70 and the YJ93.

Unread postPosted: 10 Nov 2008, 16:11
by Guysmiley
Habu wrote:
Guysmiley wrote:I seem to recall that the SR-71/A-12 was limited by maximum compressor inlet temperature.

Limited as to what? If you meant top speed, then yes. 427 max CIT. After that , the J58 would have started destroying itself.


Right, as in there wasn't a speedo in the cockpit saying "oops you're going too fast now", the limit was max CIT.

RE: Re: RE: Re: RE: Re: RE: Re: RE: The XB-70 and the YJ93.

Unread postPosted: 07 Dec 2008, 02:28
by TC
Here's another thread where I had found some overlap. They actually merged virtually seamlessly. Not bad for originally being three different topics posted over a 4 year span!

I merged all three topics, in order for this to hopefully become this site's definitive XB-70 page. I hope all Valkyrie fans enjoy it.

Re: XB-70 Valkyrie

Unread postPosted: 18 Aug 2018, 01:25
by spazsinbad
Forgot about this thread - so go here for the XB-70 Flight Manual Info:

North American XB-70 Interim Flight Manual 25 Jun 1965

viewtopic.php?f=46&t=54370

Re: XB-70 Valkyrie

Unread postPosted: 24 Nov 2019, 16:50
by tank-top
Just came across this thread. My grandfather worked on the program, he was a mathematician and came up with a formula that predicted changes in metal due to temperature change. I don’t know much more than that, wish I did. He didn’t work on the SR-71 but he designed much of the docking collar on the Apollo for the Apollo-Soyuz mission.