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Re: AO40: status

> >It's just that when I hear "leak" I picture fluids moving *away* from
> >the spin axis. 
> Unless the leak is in or near the engine, which is mounted in the center.

Whoaa, how about this!  Doesnt matter where the leak is.  If we have a 500
Kg spacecraft spinning at X RPM, and then release say 250Kg of its mass
(lost propellant) then conservation of angular momentum will require the
satellite to spin up (double its speed all else being equal (its not),
but close enough)...  

Its not that the mass had to move to the center like a spinning skater
which is a change in moment of inertia, but a loss of mass with no loss in
angular momentum.  Thus it must spin up.

How much was the mass of the propellant?
Once it was all gone, and angular moementum is conserved, then it should
be easy to calculate the change in RPM from the loss of mass alone.

How it vented, then, could add or subtract from that number too...

de WB4APR, Bob

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