Today I was doing a few long range tests with my P3S with and without windsurfer. 1st(Normal antenna): 7800 feet. Signal lost and RTH triggered. Signal was completely lost during RTH. I was worrying for a few minutes until it reconnect when it was 2400 feet away during the RTH. I turned the phantom around and sent it away for another range test. This time with Windsurfer on. 2nd(Windsurfer): I initiated RTH when it fit 9700 feet because of the low battery level. This time again, right after the phantom turn around, Signal was completely lost again until around 2400 feet again. HealthyDrones.com - Innovative flight data analysis that matters 3rd(Windsurfer): I changed the battery and send it out for another test with windsurfer on. This time I let it keep going until 12580 feet when RTH triggered. Signal was completely lost on the way back until 6000 feet away this time. HealthyDrones.com - Innovative flight data analysis that matters IMG_8484 by finalfantasyfan posted Feb 27, 2016 at 11:30 PM Can someone explain why signal was lost in all these long range test during RTH? BTW, video signal was very good without any drop during the outbound flight.