A normal glide slope is about 3 degrees. If you were doing a real steep
decent you might have a glide path of 6 degrees. Then, let's say your nose
is 4 degrees above the horizon giving us an angle of attack for the pitot
tube of 10 degrees. The cosine of 10 degrees is about .985 meaning your
airspeed indication might be 1.5% low. At 65 knots you ain't gonna notice a
half knot.

Rod
"Scott Lowrey" wrote in message
news:35Cmc.33788$TD4.5609844@attbi_s01...
If I'm descending slowly with a relatively nose-high attitude - say, in
preparation for a short field landing - does the high angle of the pitot
tube have any effect on indicated airspeed? (I suppose all designs are
different - say this is a 172.)

If the descent was steep, the relative wind would be coming from below
and forward with respect to the wing, right? Add the pitch angle, and
it seems like the pitot tube would be at a fairly angle with respect to
the direction of air flow. I suppose this is a simple angle of attack
question....

Seems like the air would be passing slightly "over" the pitot tube
opening rather than "into" it, thus reducing the measure air pressure.
Is this correct? Is indicated airspeed affected by high AOA?

-Scott