Considering the sheer complexity of the KH-9 film system it would have been one hell of a headache to work on it while in-orbit.
In fact, the length of the shuttle’s payload bay had been dictated by the requirement to carry the HEXAGON
Quote In fact, the length of the shuttle’s payload bay had been dictated by the requirement to carry the HEXAGONThere had been a lot of discussion about this precise point over the last decade. Is this the final story ? Or is there some unknown NRO (or military) satellite still classified that mandated, by itself, the shuttle payload bay length ?
Quote from: Archibald on 02/14/2017 10:27 AMConsidering the sheer complexity of the KH-9 film system it would have been one hell of a headache to work on it while in-orbit. Yeah. I have a hard time understanding how they would have threaded the film through the camera in orbit. Even if they left a bit of film in the camera sticking out either end, it would have had to be spliced to a leader coming out of the last reentry vehicle, and also spliced onto the new film supply. Then it would have to be pulled through the camera. All that in zero-g, with no way for a human to visibly monitor it.Add to that replacing the consumables. Not only the fuel supply, but they used pressurized nitrogen in the film path. Which makes me wonder how they would then seal up the system and repressurize it after bringing up the new film and SRVs. It would have been a very complex on-orbit resupply job.
Articles are now appearing that are based upon my ZEUS article. They link to my original article, but don't give me name credit for writing it:https://www.thesun.co.uk/news/2825430/us-spooks-planned-to-turn-the-space-shuttle-into-a-huge-spy-ship-to-snoop-out-soviets-cold-war-nukes/http://www.popularmechanics.com/military/research/a25133/zeus-space-shuttle-spy-plan/
Both Corona and Hexagon produced enormous volumes of photos. One can wonder if KH-11 -era digital memory storage could have handled such volume.
So ZEUS was studied from around 1978-1979 (I'll try to get exact dates). According to a declassified interview with a former congressional staffer who was involved in NRO oversight, ZEUS was really Director of National Reconnaissance Office Hans Mark's pet project. But it would have required up to four shuttle missions per year. That would have been expensive. This person claims that it was possible to upgrade the KH-11 KENNEN to increase its bandwidth and that would solve the area search requirement--so ZEUS was not necessary.There are some holes in this story, and I'd treat it all as tentative until I can get better info. One of the problems is that during the 1991 Gulf War there were complaints that the KENNEN coverage (by then it was named CRYSTAL) was "like looking at the battlefield through a soda straw." So clearly upgrades to KENNEN did not solve the area search requirement. I suspect that the upgrades increased the coverage a bit compared to the early KH-11s, but not enough to truly replace the HEXAGON's coverage.
The fate of the wide-area search role is indeed quite a mystery. It's possible it was taken over by the KH-11 for strategic search: imaging all of the USSR every year (the KH-9 spec) could be doable even with a limited field of view. For instance, Worldview 4 has a 13km field of view but still manages to image 0.6 Mkm2 per day, so napkin math says it can image the 22 M km2 of the former USSR in 36 days. Of course in reality it's going to take longer. Taken the other way around, imaging 22M km2 in 1 year means only 4 000km2 need to be imaged per satellite pass on average. That sounds feasible even with a field of view a few km wide, by acquiring long, thin strips. The same limited field of view may not have satisfied GW1 commanders who wanted to see the whole battlefield every day. So tactical wide area surveillance may not be feasible with the KH-11. That would explain the debates about 8X and other wide-area systems after the Gulf War.Another theory is that the wide area search role was filled by the Lacrosse radar sats. The last Hexagon launch is in 1986, the first Lacrosse launch is in 1988. So the dates seem to fit. Since radar allows to see at night and through cloud, and can give wide swath and high resolution (but not at the same time), it would make sense that Lacrosse was intended for tactical wide-area search, to hunt for Soviet mobiles launchers for instance. Under that theory, Lacrosse is a strategic asset to be used for nuclear conflict and was very recent in 1991, so its imagery would not have been provided to GW1 commanders. It would have been reserved to the Strategic Air Command.
Remember that much of the USSR was roadless tundra or desert where no military installation could be built without massive preliminary construction. These areas don't have to be checked very often.
Quote from: Arch Admiral on 02/16/2017 07:24 AMRemember that much of the USSR was roadless tundra or desert where no military installation could be built without massive preliminary construction. These areas don't have to be checked very often.That was actually taken into account into the specification for the Hexagon: if I recall correctly, it had to do yearly coverage of the whole USSR, and quarterly coverage of built-up areas close to the main communication axis.
Quote from: gosnold on 02/16/2017 07:09 PMQuote from: Arch Admiral on 02/16/2017 07:24 AMRemember that much of the USSR was roadless tundra or desert where no military installation could be built without massive preliminary construction. These areas don't have to be checked very often.That was actually taken into account into the specification for the Hexagon: if I recall correctly, it had to do yearly coverage of the whole USSR, and quarterly coverage of built-up areas close to the main communication axis.In fact, there's a lot of stuff about the operations of the satellites over this time (1960s into the 1980s) that we still don't know. A lot has been declassified, but nobody has really put it all together. I know a guy who had the job of turning the requirements into specific commands for the spacecraft for a little while. He said that it involved taking the requirements, then pulling out paper maps and figuring out grid coordinates, then figuring out the overhead path of the satellite and putting in pointing commands and camera commands (on/off) that was all entered into computers and then sent up to the satellites during their flights over a ground station. Lots of work.