Henry Spencer wrote:
In article . com,
Rusty wrote:
NASA has released the ESAS Executive Summary - First Installment, on
Dec. 22...

Some interesting bits of data there, not all of them obvious.

Note, in particular, that in the proposed Mars-mission profile, the
capsule has to go up to meet the MTV (Mars Transfer Vehicle) "in a
circular orbit of 800- to 1200-km altitude". Why so high?!? There's only
one reasonable answer: the MTV uses nuclear propulsion, and must start in
a "nuclear-safe" orbit, high enough that orbital life in the event of a
failure exceeds 10kyr.

The report also tells how the commitee ruled out use of
ET-only-based concepts (like the "Spencer" you discussed
a few weeks ago). They were "briefly considered", but were
ruled out on the basis of schedule and cost.

'Sounds like serious handwaving to me. The concepts were
not detailed in the report, not included in any tables, etc.
Someone might have mentioned an ET-based crew launch
in a meeting, perhaps, but I see no evidence of rigorous
analysis.

- Ed Kyle