Thread: CEV PDQ
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Old May 9th 05, 07:36 PM
Pat Flannery
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Ed Kyle wrote:

Ed Kyle wrote:


So to get the costs for a shuttle-derived system down
to something reasonable - say $400 million per flight
at four launches per year - NASA would have to establish
a program that only employed around 6,500 (total, for
everything from factory to control center to parking
lot security, etc). This is only about one-third of the
total currently involved in the space shuttle program.
(Or it could employ the same number of workers at 1/3rd
the pay.)



Or NASA could do something remarkable and design
CEV to fly atop existing EELV assets. If four
launches were to occur each year, then the EELV
production rate would be increased from 8 to 12
annually and the per-flight launch services cost
would drop from about $120 million to $80 million
(a bit of guessing).

The problem here is that you need a minimum of four EELV launches to
land a man on the Moon if the LockMart design is chosen:
Launch one carries the CEV, launch two carries the TEI stage and living
area/docking module (as shown in the LockMart "Lunar Train" drawing),
launch three carries the lunar descent/ascent module, and launch four
carries the TLI/Lunar orbital braking module.
If these are using cryogenic propellants, you've got to get them all
into LEO in fairly short order to prevent excessive propellant boil-off.
If there is a launch failure of any of the components, or a failure to
assemble them in LEO, then the whole mission is off.
I can see assembling two components in LEO- but _four_ (and that's a
minimum; it could end up being five or six)?!
Compared to Apollo's single Saturn V launch, this sucks.
With the unmanned shuttle cargo variant, you could send up everything
except the CEV in one launch, and then launch it separately with the
crew. Since you would be using two separate pads, this would save the
money on building more pads for the EELV only option's need for four or
more rapid turnaround launches to accomplish this mission.

Pat