(Mark James Boyd) wrote in message news:4095c4f4$1@darkstar...
I pulled a swivelling tailwheel off a G-103 today and was (gratefully)
reminded to not hit the long TE probe when standing up.

Why are these things so long? If they were 2" instead of
a foot long would it really matter that much? Is the airflow
really disturbed enough to make a difference?

The pitot on many power planes is maybe 2-4" long.
What's the deal here?

Has anyone tried a shorter TE probe? What's the difference
in error? Can it be compensated?


Reply: There is a measurable pressure change which varies with speed
and angle of attack in front of every surface flowing through the air.
Experience has shown that TE sensors need to be at least 1/2 chord
length in front of the fin to avoid negative effects.
Easier to learn not to bend probe than try to make TE system work with
stubby probe.
Good Luck UH