Originally Posted by Tolka
When I side slip a Cessna 172 for a cross wind landing I notice that the indicated airspeed reduces. This is not surprising. I have been wondering how much of this is due to the extra drag in the configuration and how much, if any, is due to instrument error due to the change in the airflow around the pitot tube and static ports. Any thoughts?
Tolka
I've never flown a 172 - does it have multiple static ports, or like a 152 only on one side?
If so, it's most probably because the static port is measuring a component of the dynamic pressure and the pitot will be measuring only a component of the total dynamic pressure, thus the pressure differential is lower => lowered IAS.
If you sideslip the other direction the indicated airspeed should increase (if it's only got one static port on one side).
A