Space Forum / Space Policy / July 2008

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the (FAST-SLV-like but FOUR months LATER) Direct needs TWO launches
(like in my ArianeX proposal) to accomplish the same goal of just ONE
Ares-5/cargo-Altair

that's NOT so cheap... and NOT so reliable due to the number of
launches, engines and motors that MUST work well:

cargo-Direct: TWO launches, four SRB, six RS-68, two J-2X = "12"

Ares-5: one launch, two SRB, six RS-68, one J-2X = "9"

MY Ares 5+: one launch, three SRBs, three RS-68, one J-2X = "7"

http://www.ghostnasa.com/posts/032ares5srb3.html

please consider, that, in EVERY cargo launch, the two cargo-Direct
rocket MUST work well to avoid the full cargo-mission to FAIL

last... think that ESAS is MAINLY a CARGO landing program (rather than
a crew landing program like Apollo) since it's goal is (or should
be...) to land the hardware for outposts, long stay, scientific
research, etc.

so, have a simple, cheap, reliable, easy and heavy-payload launcher,
is a key feature of the full ESAS program

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from NASA study .pdf the Direct EDS looks have TWO engines... so the
total number of engines/motors in a two-launches cargo missions should
be "13" rather than "9" of the Ares-5 and "7" of the Ares 5+, so, the
Ares-5 is about 50% more reliable than Direct and MY Ares 5+ is about
100% more reliable than Direct!!!

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just consider, that, the ABSOLUTE needs of a SUCCESSFUL rendezvous at
EVERY Direct's (cargo or crew) mission, ADDS so much risks (then a
GIANT LOSS of reliability) that OUTCLASS of ONE ORDER OF MAGNITUDE the
simple (unreliable) fact that EACH cargo-Direct needs TWICE the
engines/motors of MY Ares 5+ or 50% the engines/motors of an Ares-5
that must ALWAYS work well !!!

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