What can you do when this critical system conks out during flight?
Vacuum pumps are what power flight instruments in most light aircraft. Typically, an overhauled pump will last about 500 hours and a new one about 1,000 hours.
It would be great if we had a wear meter or some other indicator that would tell us when to expect the pump to fail, but we don't. And as Murphy's Law would have it, it quits when we need it the most. If that should happen when the airplane is in the clouds, statistically, many pilots won't survive the failure.
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