Valkyrie final flight
Salute!
The plane was amazing, but it had passed its best time to be a good threat to opposing folks.
The mid air was a pure and simple pilot factor when getting too close to a big plane that is generating a strong tip vortex. This phenomena was not well studied when then accident happened. Later in life I checked out the vortex on numerous tankers. Was like surfing, as you got further in trail you needed more and more counter aileron. My fuel flow went down maybe 20% or more, but took a lotta concentration.
BTW, the carriers have been talking bout trailing a guy across the ocean to use the vortex and save gas. Gotta love it. Maybe they should fly like the geese during migration.
Secondly, the wing tip config was sensitive, and when I was at a briefing back in 61, we were cautioned about not discussing it.
Gums sends...
The plane was amazing, but it had passed its best time to be a good threat to opposing folks.
The mid air was a pure and simple pilot factor when getting too close to a big plane that is generating a strong tip vortex. This phenomena was not well studied when then accident happened. Later in life I checked out the vortex on numerous tankers. Was like surfing, as you got further in trail you needed more and more counter aileron. My fuel flow went down maybe 20% or more, but took a lotta concentration.
BTW, the carriers have been talking bout trailing a guy across the ocean to use the vortex and save gas. Gotta love it. Maybe they should fly like the geese during migration.
Secondly, the wing tip config was sensitive, and when I was at a briefing back in 61, we were cautioned about not discussing it.
Gums sends...
Different technology to Concorde, the XB-70 was a “wave rider” using compression lift to reach the required range - hence the fold-down wingtips.
“As the competition evolved, North American exploited an aerodynamic advance that gave it the determining edge. A supersonic aircraft could have its lift-over-drag ratio increased by positioning its wing to take advantage of the pressure field that occurs behind the shock wave generated by the protruding fuselage. In North American’s design, this phenomenon—called compression lift—provided a 30 percent increase in lift with no drag penalty. Compression lift appeared to contravene the engineering rule that you never get something for nothing, but it worked.”….
“As the competition evolved, North American exploited an aerodynamic advance that gave it the determining edge. A supersonic aircraft could have its lift-over-drag ratio increased by positioning its wing to take advantage of the pressure field that occurs behind the shock wave generated by the protruding fuselage. In North American’s design, this phenomenon—called compression lift—provided a 30 percent increase in lift with no drag penalty. Compression lift appeared to contravene the engineering rule that you never get something for nothing, but it worked.”….
The XB-70 that was lost in the mid-air was the second one built - and had incorporated lessons learned from the first and was more heavily instrumented than the first. A coworker that had been at North American before coming to Boeing told me there is video of the mid-air but it was classified and never made public.
Pretty amazing some of the things we did back in the 1960's, when we didn't know what we couldn't do...
Salute!
I saw the video way back, and it was a quick roll into the tail of the Buff, but the thing did not get into what looked like a flat spin for some time.
The wing tip contribution to performance should still be a factor, just as the vortex we get on the Hornet, Viper and Rap and Stubbie from using the lex features.
What a loss, and glad we had the Black bird to do high mach research for another 2 decades.
Gums sends...
I saw the video way back, and it was a quick roll into the tail of the Buff, but the thing did not get into what looked like a flat spin for some time.
The wing tip contribution to performance should still be a factor, just as the vortex we get on the Hornet, Viper and Rap and Stubbie from using the lex features.
What a loss, and glad we had the Black bird to do high mach research for another 2 decades.
Gums sends...
Do it!
Give yourself 2 days. Yes, I mean it.
If Mrs. Treadigraph thinks a P-40 and a P-51 look the same, best go alone....ask me how I know.
An absolute must-see place.
Killed by the SA-2*. Once the USSR deployed a SAM capable of destroying high flying supersonic aircraft it lost its ability to penetrate their defences - and its role
Ecce Homo! Loquitur...
The XB-70 that was lost in the mid-air was the second one built - and had incorporated lessons learned from the first
….Although intended to cruise at Mach 3, the first XB-70 was found to have poor directional stability above Mach 2.5, and only made a single flight above Mach 3. Despite the problems, the early flights provided data on a number of issues facing SST designers. These included aircraft noise, operational problems, control system design, comparison of wind tunnel predictions with actual flight data, and high-altitude, clear-air turbulence.
NASA Ames Research Center, Moffett Field, CA, wind-tunnel studies led engineers at North American Aviation in Downey, CA, to build the second XB-70A (62-207) with an added 5 degrees of dihedral on the wings. This aircraft made its first flight on July 17, 1965. The changes resulted in much better handling, and the second XB-70 achieved Mach 3 for the first time on Jan. 3, 1966. The aircraft made a total of nine Mach 3 flights by June….
ORAC, finder of all things, didn’t Aviation week and space technology run a piece years ago about the “Aurora spy plane” being carried aloft by a new version of the XB-70? The article was roundly criticized for its accuracy.
Edit: found the article
https://web.archive.org/web/20060313...s/030606p1.xml
Edit: found the article
https://web.archive.org/web/20060313...s/030606p1.xml
Last edited by West Coast; 16th May 2021 at 23:23.
First time I went to Dayton, I wondered around for hours when I realized I'd not seen the XB-70 - and it's big enough that it would have been pretty hard to miss. So I went to one of the help desks and asked where the XB-70 was. 'Oh, that's in the annex (glances at watch) - the last bus left 10 minutes ago'
. So when I went back several years later, the first thing I did after I arrived was asked how to get to the annex to see the XB-70 
. And yes, it is huge! A 500,000 lb. aircraft that could go Mach 3, years before the first 747 rolled out 
.I've not been back to Dayton for over 10 years - I heard the XB-70 has now been moved to the main museum (not sure about all the other stuff that was in the annex - including several former Air Force One aircraft).
The XB-70 demonstrated why it's a bad idea to have a common inlet for multiple engines - on one of the high speed flights, a chunk of structure in front of the inlet broke off and was ingested. It failed all three engines on one side, and did FOD damage to all three engines on the other side...
There are three really great aircraft museums in the US - in no particular order: Dayton, Smithsonian Air and Space on the Capital Mall, and Smithsonian Air and Space Udvar-Hazy (Dulles Airport).
First time I went to Dayton, I wondered around for hours when I realized I'd not seen the XB-70 - and it's big enough that it would have been pretty hard to miss. So I went to one of the help desks and asked where the XB-70 was. 'Oh, that's in the annex (glances at watch) - the last bus left 10 minutes ago' . So when I went back several years later, the first thing I did after I arrived was asked how to get to the annex to see the XB-70 . And yes, it is huge! A 500,000 lb. aircraft that could go Mach 3, years before the first 747 rolled out .
I've not been back to Dayton for over 10 years - I heard the XB-70 has now been moved to the main museum (not sure about all the other stuff that was in the annex - including several former Air Force One aircraft).
The XB-70 demonstrated why it's a bad idea to have a common inlet for multiple engines - on one of the high speed flights, a chunk of structure in front of the inlet broke off and was ingested. It failed all three engines on one side, and did FOD damage to all three engines on the other side...
First time I went to Dayton, I wondered around for hours when I realized I'd not seen the XB-70 - and it's big enough that it would have been pretty hard to miss. So I went to one of the help desks and asked where the XB-70 was. 'Oh, that's in the annex (glances at watch) - the last bus left 10 minutes ago'
. So when I went back several years later, the first thing I did after I arrived was asked how to get to the annex to see the XB-70 . And yes, it is huge! A 500,000 lb. aircraft that could go Mach 3, years before the first 747 rolled out .I've not been back to Dayton for over 10 years - I heard the XB-70 has now been moved to the main museum (not sure about all the other stuff that was in the annex - including several former Air Force One aircraft).
The XB-70 demonstrated why it's a bad idea to have a common inlet for multiple engines - on one of the high speed flights, a chunk of structure in front of the inlet broke off and was ingested. It failed all three engines on one side, and did FOD damage to all three engines on the other side...
Dirty Beast
From watching the landing video I would suggest that, if the Valkyrie had survived to the present day, Greta Thunberg would have got it cancelled based on its emissions alone!
BV
BV
Gnome de PPRuNe
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Bob, it looks cleaner than a Convair 990 to me ! 
Thanks for the advice about Dayton and Smithsonian folks - one day! (Or preferably three or four....)
Thanks for the advice about Dayton and Smithsonian folks - one day! (Or preferably three or four....)
ORAC, finder of all things, didn’t Aviation week and space technology run a piece years ago about the “Aurora spy plane” being carried aloft by a new version of the XB-70? The article was roundly criticized for its accuracy.
Edit: found the article
https://web.archive.org/web/20060313...s/030606p1.xml
Edit: found the article
https://web.archive.org/web/20060313...s/030606p1.xml
Thanks so much for sharing that article West Coast. I have followed all things "Aurora" related over the years, but never saw that article. Good stuff. I strongly believe something large and fast was flying in the 1990's and hope someday we learn more.
If they were using a reusable XB-70 derivative to launch a smaller reusable orbiter from the 1990s, I wonder why they replaced it a decade later with the distinctly lower-tech (expendable launcher) X-37B?
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I supposedly have a bit of one. Many moons ago I ordered something from a yard in the US and it was delivered with a free gift which was this little bit of carefully wrapped up honeycomb with a note saying it had come off a Valkyrie, who am I to say otherwise, but why would anyone go to that trouble if it wasn't true, after all it was added as an unexpected addition..
IF an Aurora or XB-70 type aircraft was developed as a mother ship for a reusable orbiter, that would have been two very complex airframe systems with exotic materials, fuels, maintenance and security requirements. Not cheap or easy.
Crewed vehicles also have the highest safety requirements.
I supposedly have a bit of one. Many moons ago I ordered something from a yard in the US and it was delivered with a free gift which was this little bit of carefully wrapped up honeycomb with a note saying it had come off a Valkyrie, who am I to say otherwise, but why would anyone go to that trouble if it wasn't true, after all it was added as an unexpected addition..
Interesting use of stainless steel for the skin of the Valkyrie - apparently they didn't want to use titanium because the original plan was to build hundreds of the things and figured they could never get that much titanium, so they figured out how to use stainless without a huge weight penalty...
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Definitely silver grey metal in colour about 2 inch by 1/2 inch in size without any external skinning on it. I will photograph it.
I too have such a small sample of stainless steel honeycomb from them, although my specimen did not have any claims of association with the B-70 program.
My sample is only about 1/4" thick, so clearly a different application from yours.
I do remember the Hexcel people were seriously focused on the challenges of shaping the honeycomb. Airplanes have lots of curves and so the honeycomb has to be trimmed to just the right shape before the skin is brazed on.