airspeed indicator problem after TT2 transponder install

But wouldn't a leak in the system cause the airspeed to read lower?


My guess is the new static line that you plumbed in for the
transponder introduced a leak into the static system. *It should've
been leak tested when the transponder check was completed. Do you know
if that was done?

On Mar 3, 8:07*am, GARY BOGGS wrote:
But wouldn't a leak in the system cause the airspeed to read lower?



My guess is the new static line that you plumbed in for the
transponder introduced a leak into the static system. *It should've
been leak tested when the transponder check was completed. Do you know
if that was done?- Hide quoted text -

- Show quoted text -

That depends on whether his cabin pressure is higher or lower than
static. Easy to check with a manometer connected to static on one side
and nothing (cabin) on the other. My fancy manometer is some acrylic
tube in a 'U' shape, and some water.

Perhaps the curse I put on CP for abandoning his Canadian club (not
the whiskey!) for warmer climes (and climbs!) has had a spill-over
effect to Frank's ASI? I wouldn't have thought the sacrifice of a
PW-5 could be so powerful.

It also depends upon whether the ships static system shows true
static or not. If you read through Richard Johnson's tests you'll see
that many gliders have static systems with significant errors built in
to them. If there is more than one static source the manual will
usually specify which one to connect to as that is the one which was
used for certification testing and the placard speeds will take any
error into account.

I would reconnect everything the way it's supposed to be and then get
the pitot-static system checked out with a test set.

But wouldn't a leak in the system cause the airspeed to read lower?


That depends on whether his cabin pressure is higher or lower than
static.