kraisee - 15/12/2007 3:17 AM
5) Orion mass at 22.4mT is low. Current Orion mass is 23.6mT at docking to LSAM.
Was that number ever mentioned in any NASA document? Why it doesn't appear on any Cx document?
Based on CxP ISTIM Outbrief to JSC Engineering Mgmt from end of Nov 2007
The Orion Target 607 Mass (predicted) is 46,263 (20,084 kg) for lunar mission.
And controlled mass including Orion management reserves is 21.9mt
Cx management holds another 1.4mt reserve and Ares 1 holds 1.3mt reserve.
So if architecture and Ares reserve is allocated to Orion it could weight up to 24.5mt at the time of injection (the document still mentions -11x100nmi injection orbit).
So 24.5mt is absolute maximum hypothetical current weight of Orion. It's including payload adaptor (0.5mt) and propellant required for circularisation to 100nmi orbit where EDS+LSAM is waiting.
However, Orion weighting 24.5mt would expend all managerial reserves which wouldn't be a good practice at this design stage.
It's is quite possible that after some upgrades to Ares and Orion the real Lunar Orion in 2018 will weight 23.6mt at TLI but the current Ares V allocates just 20.2mt.