In the 05.05.01 MMD John A. Tuttle talks about the famed "drop test":

> Since leaving the military some thirty years ago I've only heard the
> term 'drop-check' a few times, but in every case it was said in jest.

I much prefer the term "percussive maintenance."

> The simple fact is, if you have to resort to dropping or hitting
> something to get it to work, face reality: there's a problem!  Don't
> abuse the item -- fix it!

There have been times with electronics where a small amount of
properly applied percussion was indeed the correct action. Usually
this is in connection with reseating circuit boards and connectors,
although there was a famous case of some disk drives that had a
stiction problem on startup. The recommended fix until a replacement
was available was to "gently" tap the drive if it didn't start spinning.

Carl Zwanzig