In article ,
Paul Mennen wrote:
I can understand why pressurized aircraft need static ports,
but why do unpressurized airplanes have them?

The venturi effect makes the pressure in the cabin lower than
the outside pressure. The same thing must affect the static ports
but instruments can be calibrated for the effect.

Look up the procedures for activating alternate static in an
airplane equipped with it. That is opening the static system to
the cabin pressure which causes airspeed and altitude to misread
(the POH will have an estimate of how much).

--
Ben Jackson

http://www.ben.com/