On 26-Jun-2004, "Carl Orton" wrote:

Guess the real question is: At what altitude is a pressure suit required?

Was SpaceShip One pressurized? All we saw was Melville with an O2 mask.


It is a certainty that SpaceShip One is "pressurized." Its occupants could
not survive in a vacuum or near-vacuum regardless of available breathing
oxygen. Their blood would literally boil. But the pressurization could not
work like a conventional airplane's, wherein outside air is mechanically
compressed and forced into the cabin. At an altitude of 63 miles there is
virtually no outside air to compress.

I don't know for sure, but I would guess that the SpaceShip One cabin is
maintained at a minimum pressure of maybe 0.4 atmospheres using compressed
gas carried aboard for this purpose. If the gas were pure oxygen, it would
suffice for breathing (as the partial pressure of pure O2 at 0.4 atmospheres
is higher than plain air at sea level). But pure O2 is hazardous, so the
cockpit environment is probably more like regular air, and the occupants
must then use supplemental oxygen.

Anybody know for sure?

--
-Elliott Drucker