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Old May 1st 04, 02:42 PM
Nicholas Fitzpatrick
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In article ,
Doug... wrote:
In article , says...
In article ,
Bill wrote:
Were all the Apollo flights made in a one-gas (pure oxygen)
environment? It seems that the thin skin of the LM made it necessary
to limit the cabin pressure to 3.5 psi and required a one-gas system.

Post-fire, Apollo used 60% oxygen 40% nitrogen as the *cabin* atmosphere
on the pad, but the crew always breathed pure oxygen, and the cabin
shifted to pure oxygen during ascent.

Pre-Fire, of course, the cabin was pressurized to roughly 17 psia of
pure oxygen. They also overpressurized the cabin at times during post-
Fire operations, but as Henry says, the air was 40% nitrogen.

I'm sure I'm not the only one who had to look this up, not knowing
what a psi is equivalent to. I'm sure everyone knows that 1 atmosphere
= 101.3 kPA ... but many of us forget that this equals 14.7 psi

So they pressurised to 1.16 atmospheres (117.2 kPa) and then dropped
to 0.24 atm (24.1 kPa).