[FPSPACE] ISS/Alpha reboost

[Geert Sassen]

Hi All,

does anyone know how ISS/Alpha is going to do a reboost when there isn't a
Shuttle docked ( for instance a manoeuvre to avoid space debris) with Soyuz
TM31 docked to Zvezda's rear port and a Progress docked to Zarya's nadir
port?

With its rear port occupied I suppose Zvezda's main engines can't be used,
while the Soyuz fuel reserves aren't big enough to provide much capacity.
During Mir missions the Progress engines were often used for reboosts, but
if the Progress is docked to the nadir port I don't know if it's engine
vector would be anywhere near the centre or gravity (in other words firing
its engine might start a spin instead of a reboost).
It still seems more logical to have the Progress on the rear port and a
Soyuz on the nadir port...

Regards,

Geert Sassen
http://www.inter.nl.net/hcc/Geert