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CEV combined with upper stage?
I have just been wondering if there would be any sense in combining the
CEV, (whatever that may be), with an upper stage propulsion system. This might give you a flexible and reusable upper stage and perhaps save some weight over a separate system approach. In addition to negating the need for a separate upper stage, this might enable a larger effective CEV on smaller effective launchers. It might also entail a fluffier effective capsule design, easing reentry requirements. With refueling this might also directly open up the earth-moon system, though it is a one size fits all approach. Would there be any useful advantage to such an approach? Is the added complexity prohibitive? Pete. |
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September 21, 2004
"Pete Lynn" wrote in message : I have just been wondering if there would be any sense in combining the CEV, (whatever that may be), with an upper stage propulsion system. This might give you a flexible and reusable upper stage and perhaps save some weight over a separate system approach. In addition to negating the need for a separate upper stage, this might enable a larger effective CEV on smaller effective launchers. It might also entail a fluffier effective capsule design, easing reentry requirements. With refueling this might also directly open up the earth-moon system, though it is a one size fits all approach. Would there be any useful advantage to such an approach? Is the added complexity prohibitive? Put a capsule on the Delta IV Medium, and lunar circumnavigation is possible, using the upper stage as your service module. In LEO, you could retrofit the upper stage into space station modules. You get three Delta IV Mediums for the price of a single heavy. Thomas Lee Elifritz http://elifritz.members.atlantic.net |
#3
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Thomas Lee Elifritz wrote:
September 21, 2004 Put a capsule on the Delta IV Medium, and lunar circumnavigation is possible, using the upper stage as your service module. In LEO, you could retrofit the upper stage into space station modules. You get three Delta IV Mediums for the price of a single heavy. Only if your service module, and all of the life support and guidance propulsion requirements, have a mass that is less than 4 metric tons for Delta IV-M or no more than about 6 metric tons for Delta IV-M+(5,4). The Apollo Command Module mass was about 6 metric tons, but its 24.5 metric ton Service Module carried 1.2 metric tons of equipment and fuel to produce electricity, water, and oxygen. It also carried a ton or more of RCS fuel and hardware needed to keep the vehicle under control. The latter masses would have to be added to the Delta IV second stage, which would directly reduce payload capability. - Ed Kyle |
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Thomas Lee Elifritz wrote in message ...
September 21, 2004 wrote: Put a capsule on the Delta IV Medium, and lunar circumnavigation is possible, using the upper stage as your service module. Only if your (command) module, and all of the life support and guidance propulsion requirements, have a mass that is less than 4 metric tons for Delta IV-M or no more than about 6 metric tons for Delta IV-M+(5,4). My group is not interested in SRB propulsion, so we are focusing on a 3 ton limit for manned lunar circumnavigation. Sounds like a slimmed-down Lunar Gemini type effort. Engineering reviews of the time called Lunar Gemini, possible, but marginal. Earth orbit Geminis weighed in at more than 3.8 metric tons. As I stated, we are focusing on a manned lunar circumnavigation for the purposes of space advocacy and IMAX and film production, solar power and hydrogen energy conversion technology promotion, hydrogen propulsion promotion, and of course, Boeing Delta IV Medium promotion. The mass fractions are tight for this mission, but should be doable with modern design criteria, techniques and equipment. To us, it makes very little sense to actually orbit and land on the moon at this point in the process. Why not do a privately funded unmanned mission(s) instead? Wouldn't that accomplish most of these goals? And might it not be possible to use a cheaper launch vehicle than Delta IV-M (Delta II, Rokot, Falcon) to actually put an unmanned spacecraft in lunar orbit? - Ed Kyle |
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September 21, 2004
ed kyle wrote: Why not do a privately funded unmanned mission(s) instead? Because the world won't be glued to their TV sets and radios for a week straight, and then go straight to the theatres to see the movie, in droves. It's all about excitement and drama. Remember what's his name .... Lindbergh? Imagine if he had a digital video recorder with him, and made a movie of his flight. We are talking about a week of intense worldwide space advocacy here. Wouldn't that accomplish most of these goals? And might it not be possible to use a cheaper launch vehicle than Delta IV-M (Delta II, Rokot, Falcon) to actually put an unmanned spacecraft in lunar orbit? But then it wouldn't be hydrogen powered, and believe me, that is the point. Thomas Lee Elifritz http://elifritz.members.atlantic.net |
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