No airspeed and/or altimeter training is essential. From personal
experience (2000+ glider hours in both rental and private gliders) you
WILL eventually lose the use of either of these instruments inflight -
and it should be absolutely no big deal!

Altimeter first - this is a plain old no-brainer. This is probably the
least valuable (after the compass) instrument in the glider for safe
flight. And it has NO serious business in the pilot's crosscheck once
the decision to land has been made - which could be at 1000' agl at the
IP, or 20 miles out on a final glide to a field you have never been to.
Any student who refers to the altimeter in the pattern should be
immediatly deprived of the use of that instrument until he understands
how to visually judge his pattern, from both high and low initial
points. I cringe when I find the altimeters in the club two-seat ships
I fly set to zero (QFE) instead of field elevation - because the
implication is that our club instructors and students are using the
altimeter as a crutch in the pattern.

Now, the airspeed indicator. Nice to have, but again, not necessary
for safe flight once the concept of angle-of-attack is thouroughly
understood. While I would probably fly my own ship knowing the
altimeter wasn't working (and wouldn't hesitate with a working GPS), I
wouldn't take off with a known bad airspeed indicator. But once
airborne, it really isn't a big deal - especially with some practice
and familiarity with the glider.

Kirk
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