Sensitivity of the gyroscopic instruments if below or above green arc

Question

What will happen to the gyroscopic instruments (heading indicator and attitude indicator) if the vacuum pressure from the engine driven vacuum pump is too high or too low?

Will the indications be sensitive or less sensitive if below the green arc on the suction gauge?

Rigidity in space principle tells us that the faster rotation of the gyros will result to being more stable. Will the indications be less sensitive then?

The housing (aircraft) moves around the gyro. The faster the gyro, the more stable it is. Therefor "readings" (changes in aircraft orientation) would be more reliable with a faster gyro. — Robert DiGiovanni, Sep 23 '23 at 17:21

niels nielsen · Answer 1 · 2023-09-21T16:47:05.727

1

The vacuum source for spinning the gyroscope inside the indicator must remain within the green arc. If it is too slow, accuracy is lost. If it is too fast, accuracy gets better but the support bearings for the gyro rotor will experience excessive wear.

edited Sep 21 '23 at 16:47

answered Sep 21 '23 at 04:34

niels nielsen

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This is exactly correct, I would just add to the answer that gyros spinning above spec will function even better as gyroscopes, up until the moment when they don't (due to bearing failure). – Kenn Sebesta Sep 21 '23 at 12:50
@KennSebesta, thanks, will edit. -NN – niels nielsen Sep 21 '23 at 16:46

Sensitivity of the gyroscopic instruments if below or above green arc

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