Quote from: lele on 06/04/2014 04:07 pmSince DC and CST also have up to 7 seats, was it a demand of NASA?No. NASA needed just 4 and 4+ is what it specified.
Since DC and CST also have up to 7 seats, was it a demand of NASA?
Quote from: lele on 06/04/2014 04:07 pmSince DC and CST also have up to 7 seats, was it a demand of NASA?What would NASA do with these additional seats?Bring all Astronauts home in one vehicle in case something happens on the ISS, maybe?
Since DC and CST also have up to 7 seats, was it a demand of NASA?What would NASA do with these additional seats?
Quote from: Elmar Moelzer on 06/04/2014 04:21 pmQuote from: lele on 06/04/2014 04:07 pmSince DC and CST also have up to 7 seats, was it a demand of NASA?What would NASA do with these additional seats?Bring all Astronauts home in one vehicle in case something happens on the ISS, maybe?That seems like the obvious advantage, but it seems likely they wouldn't have those extra three seats in there at the cost of cargo.
Quote from: Nomadd on 06/06/2014 07:10 pmQuote from: Elmar Moelzer on 06/04/2014 04:21 pmQuote from: lele on 06/04/2014 04:07 pmSince DC and CST also have up to 7 seats, was it a demand of NASA?What would NASA do with these additional seats?Bring all Astronauts home in one vehicle in case something happens on the ISS, maybe?That seems like the obvious advantage, but it seems likely they wouldn't have those extra three seats in there at the cost of cargo.On the SpaceX vehicle, at least, the extra seats could easily be taken up once only to stow on the ISS and thereafter the space used for (light) cargo.
I'm surprised nobody has brought up what seems to me the most obvious reason these commercial crew vehicles are designed to seat seven: because the Space Shuttle seated seven, and they were designed to replace the crew-carrying capability of the Shuttle.
Quote from: ChrisWilson68 on 06/08/2014 01:04 amI'm surprised nobody has brought up what seems to me the most obvious reason these commercial crew vehicles are designed to seat seven: because the Space Shuttle seated seven, and they were designed to replace the crew-carrying capability of the Shuttle.This seems realistic.I would also imagine the 7 seat focus, even if NASA only needs 4, is PR/Marketing. Making sure that any new projects (like Bigelow) who are doing pencil math for some commercial space venture can get the cost per person for transport low enough.In the speculative threads about tourism (cis-lunar or to a habitat) there is usually an assumption of a single pilot. My guess, just looking at airlines, and issues of redundancy, is that you will definitely need 2 trained crew, not 1. Not just redundancy incase the pilot is incapacitated, but I imagine there may be procedures that require 2 sets of eyes and you would want to avoid training the tourists to handle anything.With 2 dedicated crew, a 7 seater still only brings up 5 people.
Volume of spacecraft / Volume of standard human tissues = # of people that can fit in spacecraft (assuming perfect flesh/volume packing)Probably pretty cheap that way.
Quote from: RanulfC on 06/03/2014 09:42 pmAt a "guess" I'm suspecting that the majority would be to and from orbit, not any particular "destination" as it were. While he might not expect a great increase in the number of "dedicated" satellite launches hes got to "see" an increased requirement for payload to LEO including space stations, cargo and people to get to the point that something like the MCT is "justified" in operation. Its a simple matter of the scales (of economy and operations) needed to support the activities he sees.<snip>The kicker in the mix is that unlike any other transportation system we've ever dealt with on Earth, space travel doesn't have any "pre-existing" transportation market/system to tap into with the promise of increased "efficiency" over the "old" system in order to fund itself. There are no pre-existing destinations that will be faster or more economic to "get-to," no pre-existing market of goods and materials that can be transported at "reduced" cost, nothing. The ONLY current customer is really NASA for cargo and personnel, and the ONLY current market is commercial satellite launch. Everything and anything beyond those currently is going to require some sort of "bootstrapping" program to PROVIDE the basis for commercial space flight as envisioned by Musk. Its a "do-or-die" situation in that the only way to get there from here is to TRY it and see if it works.Your 2 comments fall together quite neatly. But I don't think he means LEO launches. (edit:… but he was saying 100s of Dragon V2 launches?)
At a "guess" I'm suspecting that the majority would be to and from orbit, not any particular "destination" as it were. While he might not expect a great increase in the number of "dedicated" satellite launches hes got to "see" an increased requirement for payload to LEO including space stations, cargo and people to get to the point that something like the MCT is "justified" in operation. Its a simple matter of the scales (of economy and operations) needed to support the activities he sees.<snip>The kicker in the mix is that unlike any other transportation system we've ever dealt with on Earth, space travel doesn't have any "pre-existing" transportation market/system to tap into with the promise of increased "efficiency" over the "old" system in order to fund itself. There are no pre-existing destinations that will be faster or more economic to "get-to," no pre-existing market of goods and materials that can be transported at "reduced" cost, nothing. The ONLY current customer is really NASA for cargo and personnel, and the ONLY current market is commercial satellite launch. Everything and anything beyond those currently is going to require some sort of "bootstrapping" program to PROVIDE the basis for commercial space flight as envisioned by Musk. Its a "do-or-die" situation in that the only way to get there from here is to TRY it and see if it works.
On a related note, you say "space stationS". The old ideas of space stations had an industrial base (Mars/Moon/Asteroids) as part of their history, but the recent interest has approached them as a first step. ie: Mars comes first, then space stations built with Mars materials.
Of course it was based on the premise that launch from Mars was far cheaper than launch from Earth, but perhaps that assumption will need to be revisited in the near future.