Reasonable Minimal Size for a 2-Man Capsule?

Hey all,
Just wanted to pop in for a second to get people's opinions on a
technical question. I've been doing some high-level number crunching
for lunar missions in my spare time again, and was trying to come up
with a reasonable size for a 2-man crew capsule.

Basically, this crew capsule wouldn't be performing any of the major
burns, just providing enough propulsion capabilities to handle post-TEI
mid course corrections and reentry. It would need to have (obviously)
a heat shield and a landing system (parachutes or otherwise). The
capsule would need to support the two-man crew for up to 8 days (ie a
1-2 day lunar stay), and include a hatch, and room for two spacesuits.
The idea would be to have it just roomy enough to be workable for 8
days, but otherwise as small as reasonably possible.

Anyhow, what do you guys think a reasonable weight target for such a
design would be? The 3-man Apollo CM was about 5800kg, and the 2-man
Gemini was about 3800kg. t/Space was talking about 4000kg for a 4-man
reusable orbital capsule, and SpaceX is looking at 7 people for less
than 9000kg including the escape tower. I know that George Herbert has
suggested that a 1-person capsule could be doable in the 300-400kg
range, though that seems a bit sporty.

I guess I'm having a hard time coming up with a realistic number
because most of the previous manned capsules were done with 60s era
manufacturing, electronics, and power systems. And most modern designs
have different design goals in mind.

Anyone have any thoughts? Henry? Derek? Rand? John?

~Jon

.

Relevant Pages

  • Re: Reasonable Minimal Size for a 2-Man Capsule?
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