News f2s wrote:
"Jeff" wrote in message
...

BTW, I learned celestial navigation while working on a craft
that used gyros for stabilization. When the gyros failed, the
craft was scuttled!


Did it use the gyros to hold the craft rigid? or did it use them
to drive stabiliser vanes to counter roll?

The gyros were used directly to keep the craft at the correct
attitude. There were six onboard when launched, and they failed one
by one. When they all died, it was abandoned and scuttled. BTW, the
cost of the craft was $250,000,000, 28 years ago.