Is a transponder required to be in my aircraft for PowerFLARM to work?
No. PowerFLARM does not require your glider to be transponder equipped. Glider-to-glider collision avoidance is best handled with the FLARM-to-FLARM collision avoidance technology which is superior to the transponder generated information for use by PowerFLARM. Obviously, the PowerFLARM is not providing any collision avoidance information to GA aircraft.
