On Thursday, September 28, 2017 at 9:51:13 AM UTC-7, Ramy wrote:
Now that the TN72 is available and relatively low cost, is there a reason for those of us with TT21/TT22 in experimental gliders to wait till 2020 to install the TN72 vs installing now to become more visible to more aircrafts?

None at all. And there is nothing magic about 2020 that should affect your decision here. Please get started and go do it. We are talking the incremental costs of a few long aerotows.

(since I know you fly near SFO Class B at times) keep in mind doing that will not give you access to those areas where the glider exemption does not remove ADS-B Out requirements after 2020 (Class B and C and related, read the regs for details). For that you would need a TN70 based install.

I am curious to hear from folks who already done that.

Ramy