Transponder TT21 versus TT22 - Considerations

Just send off this question to Trig's North American Support. After having a telcon with him today regarding these issues, he stated that Trig has verbally told him that the TT21 would NOT be compliant for the ADS-B out mandate in 2020. This was based on some recent conversation with the FAA dealing with the ADS-B out program. He recommended that the question be passed on to Trig so they can give their formal reply:


Bruce Grammon
TRIG Support North America
Mid-Continent Instruments and Avionics

Bruce,

I'm a pilot with plans on installing the outstanding Trig transponder in my sailplane for flying in the Western United States where altitudes 15,000 to 18,000 frequently occur. But, I'm uncertain which model I should buy. My considerations:

1) I fly above 15K msl frequently; Is there any regulatory or practical reason to use the higher power TT22?

2) Cost is a consideration. Gliders are not mandated to use transponder below Class A airspace (excepting Class B and C). Nonetheless, I consider it a safety issue and morally correct to avoid mid air collisions with airliners.

3) Power consumption is a factor. What is the average power use increase using the TT22 versus the TT21?

4) Should the FAA change their mind regarding ADS-B out compliance and require it for gliders, can the TT21 be used for ADS-B out in the future?

Please forward these questions to Trig to help me and fellow glider pilots make the right decision on selecting Trig transponders.

Walter Rogers "WX"