grumman aa-5 stall warning delay

On Jan 5, 11:45*pm, wrote:
H@mst3r wrote:
no, it moves freely and has just been rebuilt by our AMO.

Brand new case for someone to investigate

The stall warning on Grummans is a spring loaded vane screwed to a switch..

When the airflow where the vane is mounted starts flowing up, the
switch closes and the alarm sounds.

It is impossible for there to be a delay between the switch closing
and the alarm sounding.

That leaves either the vane being bent, positioned incorrectly or a
too stiff of a spring, thus requiring being deeper into the stall before
the switch closes.

I would question how the switch could be "rebuilt" locally as the switch
is proprietary and not generally available as a part.

--
Jim Pennino

Remove .spam.sux to reply.

Most likely it's the buzzer. Some of those were a small
electromechanical horn, which uses a small coil, a diaphragm and a
switch on the diaphragm that opens the coil's supply when it's
displaced. The resulting oscillation makes lots of noise. When that
switch gets dirty, it might be a few seconds before the diaphragm gets
around to moving enough to start the oscillation. Probably need a new
horn. The other possibility is a bad connection somewhere in the
circuit, most likely the ground connection at the horn.

Dan