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Why so few ATVs ?
JF Mezei wrote on Thu, 27 Sep 2018
12:50:46 -0400: On 2018-09-27 07:03, Jeff Findley wrote: The US arrangement with Russia is the glaring exception to the rule. It was first made to keep Russia occupied in space instead of selling missiles to "rogue nations". Initially, the USA were guests on the Russian segment, and reliance was reduced as the USA segment gained ECLSS and eventually a hab module (kitchen, toilet, berths) That 'guest' period was quite short and early crews were small. The original intent was that Zvesda would provide all life support for a crew of six. The US segment gained life support when Destiny was added (as I recall it got 'supplementary' life support in one of the racks because the Russian system kept breaking down). There was no 'hab' module. It was cancelled. Zvesda only has two 'berths'. Everyone else sleeps by pretty much just hooking their sleeping bags up any old place in any old module. Let's look at the dates. The first Expedition (what they call the crew swaps) launched at the end of October in 2000 on a Soyuz and was three people; two Russians and an American. At that time, ISS consisted of Zarya, Unity, Zvezda, and the Z1 Truss. Lots of room in Unity to hang a bag and sleep. While those first three crew were up, they added the P6 Truss and solar arrays, Destiny, ESP-1, and the Canadarm. From that point on, all trips up and down were via Shuttle until near the end of 2002. Permanent crew was three and there was a single Soyuz docked. While Soyuz is supposedly only good for 6 months or so docked to ISS, I don't see another Soyuz launch until November of 2002, which would leave the Soyuz docked to ISS being there for two years unless they were tossing and launching empty Soyuz vehicles every six months. The Shuttle doing US crew exchanges reduced but did not eliminate the need for Soyuz. They still needed "escape pod" seats, they owb seat liners and Sokhol suits and Soyuz training. The Shuttle did ALL crew exchanges for the first two years or so that ISS was manned. The first crew of three came up on a Soyuz, but it was Shuttle all the way from there until November of 2002. I don't believe we were ever set up to be escaping on Soyuz. I think the assumption was that if there was an emergency they would be retrieved by Shuttle. At one point we talked about developing an escape vehicle, but it, like the hab module, was cancelled. HGowever, during that period, providing "escape pod service" to Americans required a Soyuz be empty at the station. But it allowed Russia to use those seats on the up/down trips (such as space tourists, and visiting russian astronauts for 2-3 stays) Except they didn't do that. 'Space tourists' were damned thin on the ground and I simply don't find it credible that the Russians were launching empty Soyuz vehicles and then throwing them away empty after six months or so. So the end of the Shuttle would have had financial impacts since Russia could no longer sell those seats for visiting crews. Not much of an impact, since they didn't sell very many of those seats. BUT, the major cost to Russia was when the USA became ready to increase ISS crew size and needed their own Soyuz as escape pod. (Whether Shuttle worked or not) so it is normal that the USA would have had to pay Russia for ecsape pod service at he very least, and pay more when that Soyuz was used both for transport and escape pod after Shuttle retirement). Why would you have to pay more for transport? It's still a Soyuz launched and reentered, regardless of whether it's done full or empty. According to you, everyone was already being prepped as if they were going to ride Soyuz whether they ever did or not, so no additional cost there, either. So even if Shuttle had not been retired, the USA would have still needed to pay for extra Soyuz that allowed USA to had its own 3 person crew on ISS. I don't believe that's true. Retirememt of Shuttle increased the costs because Russia couldn'tuse those seats during up/down trips for visiting astronauts/tourists. How did these 'space tourists' escape if they were riding up in the 'US' escape pod? Since those seats in this hypothetical 'escape pod' would be filled by Americans and the other Soyuz would be filled by Russians, do you think they would just tell the tourists 'hard cheese' and abandon them? Here is a question: Assuming Dragon starts crew shuttle service and escape pod service in 2019, how "late" is this on an ISS timeline? That's certainly worded as a question, but I don't understand what you're asking. In other words, Was there expectation that the USA would gain escape pod capability by the time the ISS was ready to get 6 crewmembers? Or was there knowledge that 6 crew would happen well before US "escape pod" capability and thus that there would be a need to buy Soyuz for a number of years between ability of 6 crewmembers and abiulity to have escape pod capability ? Those are certainly 'other words', but they don't seem related to your original words. However, to answer THAT question, ISS crew was three or less (with the exception of a week or two overlap, when two crews were present) until 2006 or so. The idea of an ACRV was cancelled in 2002, long before the expansion of the crew beyond three people, and the Commercial Crew effort was never supposed to deliver anything until, well, around now. -- "Some people get lost in thought because it's such unfamiliar territory." --G. Behn |
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