On Thursday, January 14, 2021 at 8:23:00 AM UTC+1, wrote:
Moshe,

Only TIS-B has position uncertainty from the imprecision of SSR, which varies with the distance from the radar station. Both ADS-R and TIS-B have some position error from delay introduced by the reception-processing-rebroadcast sequence. ADS-B is not designed for close proximity collision warning - it's more a traffic separation tool - 5 miles and 1000 feet. I believe you can get ADS-R/TIS-B traffic alerts at, say, 1 mile, depending on on your display.

Yes. We will try enabling traffic alerts for ADS-R, but I'm a bit reluctant since correctly detecting tow trains may be hard, given the (uncertain) time delay.

Honestly, the dual-ADS-B setup in the US - of which ADS-R/TIS-B is the consequence - is a surprisingly complex beast. We're thus happy to hear your feedback, preferably with IGC log files sent along to .

Thanks
- Urban