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major_clangerLast week the US National Reconnaissance Office released a considerable amount of information about two of the second generation of US spy satellites: the high-resolution KH-7/KH-8 GAMBIT and the massive KH-9 HEXAGON. Among the materials placed online (although right now the relevant site seems down) was a programme history of GAMBIT; reading through it, I found the following remarkable snippet on page 81:
"On 20 May 1972*, ground stations lost contact with GAMBIT-3 No. 35 (which showed pneumatic-regulator failure) during ascent. As usual, an attempt was made to predict the impact point and a zone over South Africa was indicated. Five months later, Dr. Water F. Leverton, an Aerospace Corporation employee who had worked on GAMBIT-3, was visiting the London office of his company, where he heard that some "space material" had been found on a farm 75 miles to the north. He arranged a visit to the Royal Aircraft Establishment at Farnborough, where debris was displayed on a laboratory bench. He found three classes of objects: a spherical titanium pressure vessel, some circuit boards of US manufacture, and several chunks of glass which could be arranged into a pie-shape. The glass had the characteristic [REDACTED] used by Eastman Kodak and [REDACTED]** was convinced he was looking at GAMBIT debris. Eyewitness accounts also strengthened his belief: the objects had been seen falling to earth on 20 May. Discreet arrangements were made for the transfer of these materials to the United States, where they could take their place with the debris from CORONA No. 77 - another "errant bird" which had landed in Venezuela in 1964."
* The original text says 1976 but this is clearly a typo as a table in the same document says 1972 and other sources agree this date for one of the reported Titan-3B launch failures.
** An odd redaction as from context it must be Dr Leverton who is being referred to.
So what happened? GAMBIT-3 #35 must have very nearly made it into orbit to have got from Vandenberg, near Los Angeles, to England. Evidently an upper stage problem left it in such a low orbit that it rapidly re-entered, certainly before ground controllers could use its on-board orbit adjustment thrusters to stabilise the orbit as happened with one or two other such flights. Launched into a polar orbit, the ground track of GAMBIT-3 #35 would have been very similar to this plot of a more recent launch. Indeed, that shows that a Vandenberg launch into polar orbit flies over north-west Europe on the second revolution.
It sounds as if the NRO were aware that GAMBIT-3 #35 had limped into a very low orbit but that it had quickly re-entered. From that ground track, a guess of re-entry over southern Africa was reasonable, but evidently it lasted a dozen or so minutes more and actually must have re-entered over France, passing over the English Channel to break up and disintegrate over the Home Counties. Indeed, it must have narrowly missed hitting London itself.
The report is vague as to exactly where the debris was found. '75 miles north of London' covers an arc roughly from Corby round through Peterborough towards Downham Market. It would be interesting to search local newspapers for reports of satellite debris - or UFOs. I'm also wondering if an FOI request to the MOD might turn up any references to findings of satellite debris, or even a request from the Americans to return some bits of a rather sensitive project...
"On 20 May 1972*, ground stations lost contact with GAMBIT-3 No. 35 (which showed pneumatic-regulator failure) during ascent. As usual, an attempt was made to predict the impact point and a zone over South Africa was indicated. Five months later, Dr. Water F. Leverton, an Aerospace Corporation employee who had worked on GAMBIT-3, was visiting the London office of his company, where he heard that some "space material" had been found on a farm 75 miles to the north. He arranged a visit to the Royal Aircraft Establishment at Farnborough, where debris was displayed on a laboratory bench. He found three classes of objects: a spherical titanium pressure vessel, some circuit boards of US manufacture, and several chunks of glass which could be arranged into a pie-shape. The glass had the characteristic [REDACTED] used by Eastman Kodak and [REDACTED]** was convinced he was looking at GAMBIT debris. Eyewitness accounts also strengthened his belief: the objects had been seen falling to earth on 20 May. Discreet arrangements were made for the transfer of these materials to the United States, where they could take their place with the debris from CORONA No. 77 - another "errant bird" which had landed in Venezuela in 1964."
* The original text says 1976 but this is clearly a typo as a table in the same document says 1972 and other sources agree this date for one of the reported Titan-3B launch failures.
** An odd redaction as from context it must be Dr Leverton who is being referred to.
So what happened? GAMBIT-3 #35 must have very nearly made it into orbit to have got from Vandenberg, near Los Angeles, to England. Evidently an upper stage problem left it in such a low orbit that it rapidly re-entered, certainly before ground controllers could use its on-board orbit adjustment thrusters to stabilise the orbit as happened with one or two other such flights. Launched into a polar orbit, the ground track of GAMBIT-3 #35 would have been very similar to this plot of a more recent launch. Indeed, that shows that a Vandenberg launch into polar orbit flies over north-west Europe on the second revolution.
It sounds as if the NRO were aware that GAMBIT-3 #35 had limped into a very low orbit but that it had quickly re-entered. From that ground track, a guess of re-entry over southern Africa was reasonable, but evidently it lasted a dozen or so minutes more and actually must have re-entered over France, passing over the English Channel to break up and disintegrate over the Home Counties. Indeed, it must have narrowly missed hitting London itself.
The report is vague as to exactly where the debris was found. '75 miles north of London' covers an arc roughly from Corby round through Peterborough towards Downham Market. It would be interesting to search local newspapers for reports of satellite debris - or UFOs. I'm also wondering if an FOI request to the MOD might turn up any references to findings of satellite debris, or even a request from the Americans to return some bits of a rather sensitive project...
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no subject
Date: 2011-09-21 10:03 pm (UTC)Shame we'll have to wait 20 years before we hear what happened to the KH11 replacements, cos thats a real hall of mirrors.
(I forget, you'll have a... different perspective on such matters)