On Sat, 6 Dec 2003 11:15:31 -0000, "Brian Gaff"
wrote:

Re below, it shows the prudence of having two different techniques for
attitude control though, in my view. Good bit of design sense there in the
original design.

anyway, exactly how big are these gyros?

Apparently somewhere in between the size that will pass through a Progress
docking port and that which will pass through a Shuttle docking port.

Could one be sent via some kind of expendable launcher and a cobbled
together manoeuvring system?

I can't imagine they'd send something "cobbled together" anywhere near
the station for a rendevous. Seems to me it would need to be grappled,
and also have an adapter allowing it to be docked to a Shuttle port. They
couldn't just pluck the gyro out of it's cargo hold and stick it in an
airlock, could they? So, you're kinda talking about developing a new
cargo ship, cobbled together or not. And doing it before the Shuttle's
return to flight.

I think the sensible course is to do what they're doing. They still have
3 functioning gyros (2 are required). Giving them a break by utilizing the
Russian thrusters for a while might keep both systems available until a
Shuttle can bring replacement gyros. This doesn't strike me as being a
dire emergency quite yet.

Dale