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Old 13-May-2008, 09:29 AM
JonClarke JonClarke is offline
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Quote:
Originally Posted by neilzero View Post
Fast single trip ships can have very high re-entry speeds, so that may not be an argument against cyclers.
There is no reason why non-cycler craft haave to be to be single mission.

Approach velocities for Earth and Mars can be extremely high with cyclers, of the order of 12 km/s at Mars and 11 km/s at Earth over and above minimum energy transfer approach speeds. Include these and martian escape velocity means that total approach velocities for Mars and Earth would be of the order of 19 and 22 km/s in the worst case scenario. This is the price of using the intrinscially inefficient orbits required by cyclers. http://www.troymcconaghy.com/storage/AIAA_2002-4420.pdf

Jon
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