Text 13237, 41 rader
Skriven 2010-12-16 11:25:37 av Michiel van der Vlist (2:280/5555)
     Kommentar till en text av Ward Dossche (2:292/854)
Ärende: Do Reindeer fly ?
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Hello Ward,

 RW>> But, to be more specific, the orbital maneuvering system provides
 RW>> the thrust for orbit insertion, orbit circularization, orbit
 RW>> transfer, rendezvous, deorbit, abort to orbit and abort once
 RW>> around and can provide up to 1,000 pounds of propellant to the aft
 RW>> reaction control system.



On Wednesday December 15 2010 11:54, you wrote to Roy Witt:

 WD> That propellant however is used only outside the Earth's atmosphere.
 WD> Hydrazine is not something that can be burned in the booster engine
 WD> plus any surplus hydrazine is ejected in space prior to re-entry.

Hydrazine is dangerous stuff. Poisonous and highly inflamable. That is why it
is ejected before re-entry.

But that the Orbital Manouvering System is never used in the atmosphere does
not mean that it is not possible.

 WD>> To achieve sustained flight, it needs to be able to become airborne,
 WD>> which it can't.

Part of ther OMS consist of two rocket engines mounted left and right of the
top main engine. It can provide 6000 pounds of trust for just over 5 minutes.
Good for a delta vee of 300 m/s.

http://spaceflight.nasa.gov/shuttle/reference/index.html

I think that should be enough to get it off the ground. As far as I can see
such a take-off does not violate the laws of physics. Of course, it is not
recommended. You may get airborne, but then you will find yourself at low
altitude without fuel and the runway behind you...


Cheers, Michiel

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