Progress Deorbit & Misc

> Date: Fri, 23 Nov 2001 12:12:30 -0500
>
>...The point is that keeping
>more objects (materials) on ISS will cause more drag (unless what is added
>goes inside something already there) and that will cost more in fuel to
>boost it, to keep it at the assigned altitude.

Minor point - adding concentrated masses like a Progress would increase the
ballistic coef. (making ISS fly more like a bullet than a parachute) and
reduce the effect of drag.. slightly. It's those big area, low mass parts
like solar panels that really slow it down. (This will be something MirCorp
will need to worry about if they try to stay co-orbiting with ISS with
their little Mini Station 1 - they will need to brake as well as boost.)

The real reason to get rid of Progress, from the point of view of Mission
Control, is the risk of collision or interference with other vehicles. Just
like you wouldn't want a bunch of empty sailboats drifting around in front
of your harbor. The rules on other vehicles operating near ISS are very
strict - so any storage solution would need to move salvaged vehicles to a
higher orbit. Maybe boosting up by only 100 km would be acceptable (and
this might already be within the capability of the current deorbit burns).
Or maybe you could send it over to MirCorp's Mini Station for the needed
adjustments. I think the real value in a salvaged Progress would be the
pressure vessel. But you would still want to deal with trash the station
packs into it before disposal.

- Eric Dahlstrom

Progress vehicle (current M1 type)
http://www.astronautix.com/craft/proessm1.htm

MirCorp Mini Station 1 design image..
http://www.mirstation.com/images/frontpage.jpg
..and press release
http://www.mirstation.com/pressrelease_4.html

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