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ORAC
24th Nov 2020, 07:26
The Air Force's history office just published a new official history on the XB-70 program, which you can read here:

https://media.defense.gov/2020/Nov/23/2002540204/-1/-1/1/B-70%20VARIANTS.PDF (https://t.co/uOcNFMEpG3?amp=1)

https://cimg5.ibsrv.net/gimg/pprune.org-vbulletin/1394x1042/image_3201b3eeb7fb60152daafefa6a06b409937e48f4.jpeg



https://twitter.com/TheDEWLine/status/1330955341530542084?s=20

Asturias56
24th Nov 2020, 07:38
looks like Dreamtime - everyone chipping in with their latest idea....................

CNH
24th Nov 2020, 18:44
Why bother with a B 70 launching a Minuteman missile when a silo equally well and far cheaper?

ORAC
24th Nov 2020, 20:55
The same reason they trialled dropping one out if the back of a C-5 - airborne alert.

A problem of the silo based Mx is that at of a response to an enemy 1st Strike - If a threat is inbound you can either use it or lose it, losing the option to let it play out out before responding. With an airborne response you can afford to wait till after the strike to assess and respond.

But isn't that the role of the SSBN force, you may ask.

Firstly the B-70 was in the era before Poseidon/Trident, secondly it would have provided redundancy, and a raison d’etre for SAC (which it subsequently lost).

tdracer
25th Nov 2020, 00:29
The same reason they trialled dropping one out if the back of a C-5 - airborne alert.


My first thought was that using a Mach 3 bomber to launch an ICBM would be serious overkill, but then I remember that - at the time it was being tested - it was far and away the largest aircraft flying - something like 250 tons.
The C5 and 747 came along a few years later.

Asturias56
25th Nov 2020, 12:03
Yeah ORAC but you had Polaris at the time IIRC - 41 (!!!) SSBN's............

More a plan for the USAF to keep flying manned aircraft as part of the Triad.

bobward
25th Nov 2020, 13:57
You could also launch from anywhere, complicating the enemies opportunity to use ABMs.

Asturias56
25th Nov 2020, 15:25
what was the endurance?

ORAC
25th Nov 2020, 21:26
Well, it had a range of over 3,700nm with a fuel load of over 300,000lbs and a cruise speed of M3.0.

So I imagine at subsonic loiter with a couple of engines shut down, plus a KCi-135 as an escort - lots....


https://cimg8.ibsrv.net/gimg/pprune.org-vbulletin/1213x906/image_2fe3fbf96cd596e446c058101c7d2134c677476b.jpeg

Asturias56
26th Nov 2020, 09:34
thats a great graphic - I'd never realised it was significantly bigger than a B-52

But if you're going to throw ICBM out of it I'd have thought endurance rather than top speed was a major requirement - otherwise you are likely to get caught on the ground.

old,not bold
26th Nov 2020, 17:28
Why bother with a B 70 launching a Minuteman missile when a silo equally well and far cheaper?
One reason might be simply that the silo is in a known location and can't duck.

TURIN
26th Nov 2020, 18:15
Wow, I had no idea it was that big. Must get over there to see it one day.

tdracer
26th Nov 2020, 18:38
Wow, I had no idea it was that big. Must get over there to see it one day.
I've seen it a couple of times (Dayton) - and it is huge (especially for it's day - hard to believe they did that nearly 60 years ago - when we didn't know what we didn't know).
Word of warning - unless somethings changed, the XB-70 is in a remote building from the main museum buildings. You need to take a shuttle bus over and back - which has limited hours of operation.

eckhard
26th Nov 2020, 18:49
It was in one of the main hangars when I visited in June, 2019.

Asturias56
27th Nov 2020, 08:56
One reason might be simply that the silo is in a known location and can't duck.


same applies to a B-70 Airbase - they couldn't operate from any old field. That's why I was asking about endurance - if its limited then they have to spend a lot of time on the ground on Quick Alert. Also given the unit cost you could probably buy a lot of Minutemen silos for one ICBM equipped B-70

tdracer
27th Nov 2020, 23:25
It was in one of the main hangars when I visited in June, 2019.
Good to hear - it's been about 10 years since I was there, I knew they were planning an expansion of the main buildings but didn't know the status.
However the first time I visited (around 2000), I spend a couple hours looking around the main museum buildings, but realized I'd not seen the XB-70 (and it's big enough it would be hard to miss), so I asked at a help desk. 'Oh, that's in the annex, you need to take a bus over. The last bus left 15 minutes ago....:uhoh:...

eckhard
28th Nov 2020, 10:08
https://cimg7.ibsrv.net/gimg/pprune.org-vbulletin/2000x1504/55255ba4_1c38_465e_ac8d_6b51f473788c_342b580999491021f832bf4 f25f32378604caa89.jpeg
Here she is

TURIN
28th Nov 2020, 10:12
Good to hear - it's been about 10 years since I was there, I knew they were planning an expansion of the main buildings but didn't know the status.
However the first time I visited (around 2000), I spend a couple hours looking around the main museum buildings, but realized I'd not seen the XB-70 (and it's big enough it would be hard to miss), so I asked at a help desk. 'Oh, that's in the annex, you need to take a bus over. The last bus left 15 minutes ago....:uhoh:...
Same thing happened to me when I went to Kennedy Space Centre. I was absolutely gutted not to see the Saturn 5, as we spent so much time in the new Atlantis exhibit. I went back a few years later. Not disappointed.

Less Hair
28th Nov 2020, 11:34
Interesting how much they thought about dropping or launching stuff in supersonic flight as early as back then. The SR-71 even tested it.
Strange that those plans never seem to have materialized, say to launch ramjet-drones into contested airspace, at least it got never admitted.
Now extrapolate the same spirit and think what might be possible and done today?

Coltishall. loved it
28th Nov 2020, 12:33
Lovely aircraft. It was outside when I saw it mid 1980's

ORAC
30th Nov 2020, 09:06
Interesting how much they thought about dropping or launching stuff in supersonic flight as early as back then. The SR-71 even tested it.
Strange that those plans never seem to have materialized, say to launch ramjet-drones into contested airspace, at least it got never admitted.


Lockheed D-21......

https://en.wikipedia.org/wiki/Lockheed_D-21

.....The fourth and final launch from an M-21 on 30 July ended in disaster. Unlike the three previous launches this one was performed straight and level, not in an outside loop (https://en.wikipedia.org/wiki/Outside_loop) to assist in the separation of the drone from the aircraft. The D-21 suffered engine problems and struck the M-21's tail after separation, leading to the destruction of both aircraft. The two crew ejected and landed at sea. The pilot, Bill Park, survived, but the Launch Control Officer, Ray Torrick, drowned.[10] (https://en.wikipedia.org/wiki/Lockheed_D-21#cite_note-gg_p108-10)[11] (https://en.wikipedia.org/wiki/Lockheed_D-21#cite_note-Landis_p24-5-11)

Following the accident, Johnson suggested launching the D-21 from the Boeing B-52 Stratofortress (https://en.wikipedia.org/wiki/Boeing_B-52_Stratofortress) bomber and adding a solid rocket booster to get it up to speed.[12] (https://en.wikipedia.org/wiki/Lockheed_D-21#cite_note-Landis_p25-6-12) ......

Four operational missions with the D-21B took place under the codename of Senior Bowl. These were conducted over the People's Republic of China (https://en.wikipedia.org/wiki/People%27s_Republic_of_China) from 9 November 1969 to 20 March 1971 to spy on the Lop Nor nuclear test site (https://en.wikipedia.org/wiki/Lop_Nor#Nuclear_Weapons_Test_Base). The USAF's 4200th Support Squadron, based at Beale Air Force Base (https://en.wikipedia.org/wiki/Beale_Air_Force_Base), California, flew the missions, usually from Andersen Air Force Base (https://en.wikipedia.org/wiki/Andersen_Air_Force_Base) in Guam (https://en.wikipedia.org/wiki/Guam).[19] (https://en.wikipedia.org/wiki/Lockheed_D-21#cite_note-19)

The Chinese government never reported spotting the D-21B in flight. The first one failed to turn around and continued straight on, crashing in the Soviet Union.[20] (https://en.wikipedia.org/wiki/Lockheed_D-21#cite_note-CIA_513A-20) Another test flight was conducted on 20 February 1970 in a successful attempt to correct any problems. The second operational mission, however, was not until 16 December 1970. The D-21B reached Lop Nor and returned to the recovery point, but the hatch had a partial parachute failure and was lost at sea with its photographs.[17] (https://en.wikipedia.org/wiki/Lockheed_D-21#cite_note-gg_p118-17)

During the third operational mission, on 4 March 1971, the D-21B flew to Lop Nor and returned, and released the hatch, which deployed its parachute, but the midair recovery (https://en.wikipedia.org/wiki/Mid-air_retrieval) failed and the hatch fell into the water. The destroyer (https://en.wikipedia.org/wiki/Destroyer)that tried to retrieve the hatch ran it down and it sank. The fourth, and last, operational flight of the D-21B was on 20 March 1971. It was lost over China on the final segment of the route over China's Yunnan province (https://en.wikipedia.org/wiki/Yunnan_province);[21] (https://en.wikipedia.org/wiki/Lockheed_D-21#cite_note-21) wreckage was found by local authorities. In 2010, after being in the junkyard of the China Aviation Museum (https://en.wikipedia.org/wiki/China_Aviation_Museum) for years, the wreckage was moved to the exhibition area.[22] (https://en.wikipedia.org/wiki/Lockheed_D-21#cite_note-22)

On 23 July 1971, the D-21B program was canceled due to its poor success rate, the introduction of a new generation of photo reconnaissance satellites (https://en.wikipedia.org/wiki/Satellite), and President Richard Nixon (https://en.wikipedia.org/wiki/Richard_Nixon)'s rapprochement with China.[23] (https://en.wikipedia.org/wiki/Lockheed_D-21#cite_note-23) .....