Is the glider pilot flying off of an altimeter set at zero, or is he
flying GPS altitude, and if he is flying with his altimeter set at
29.92,

Come on Snoop you should know the answers to these. The pilot is
instrument rated and as a result has been trained to fly in IFR
airspace. He will set it to 29.92 as he is supposed to.


how far out of tune is his old altimeter that may not have seen
the bench since it was new?

IF flying in Class A airspace (diffenent from Cloud Flying) he will
have a Mode C Transponder that has been checked with in the last 24
months.

Don't know, food for thought, I hope. What
I do know is that altimeters that have not been bench checked in a
while can be waaay off.


Also as is standard procedure the Controll will confirm that
Transponder and the Altimeter coorsponde within a reasonable tolerance.




Brian
CFIIG/ASEL