rip wrote in message ...
Unless the blockage rattling around was after the ASI and before the VSI
and ALT. Interesteing idea.


I'm sure that ASI did not have oblivious oscillation like the VSI or
ALT's big needle movement. I guess the reason behind it was because
of the fraction. (if not because of place of blockage)

What I mean by fraction is that it might take more air pressure to
move the ASI needle than to move VSI and ALT needles. In that case,
ASI needle oscillation will be not that obivious to observe.

BTW, one of my instructors told me today that he guesses the
oscillation might be caused by the water plus the engine vibration
(that makes the blockage on and off).

-cpu