Ad 2012-08-06

I've used the gps method per para (g)( and found my Alon's airspeed indicator error almost identical to that shown in the "Flight Manual" from Univair (that is a copy of what Alon provided to the British). There are several spreadsheets available online, requiring flying either a triangular or rectangular course at different airspeeds and noting the ground speed on each leg, i.e. @ 50, 65,80, 95,110, 125 indicated. Pro tip-still air helps.

How did you do the 4yr airspeed certification required by this AD?