reply to post by Manasseh
Manasseh, lift is created by the MOTION through the air. Bernouuli's Principle.
Continued forward motion through the air will be imparted through various forms of energy....THRUST is one way, GRAVITY is another. Either way, lift
is produced. IF there is no thrust, then Gravity is used, at the expense of using some of your 'potential energy' (altitude) in exhange.
I mentioned the APU only because I was pointing out how useless a regular jet airplane would be, out of its environment...such as in a vacuum.
NOW, here's where it gets real interesting....the Shuttle uses an Auxilary Power Unit....three, I believe....but while APU is the same acronym, they
are very, very different from an jet's APU.
Your typical Boeing has an APU, it uses the Jet fuel and air, to procuce power to run the Electrics and Pneumatics.
The Shuttle's APUs typically provide Electrics....no need for Pneumatics.
AND, the Shuttle's APUs....they operate differently than an airplane's. BUT, they use some combination of chemicals, that when properly combined,
provide electricity. Please don't ask me to name the chemicals, it's not my field of expertise....it's the basic concept that I understand.
Think of them as really powerful batteries, if that helps......




