I had a very different experience, however I also was using an X8R with
PCB antennas (not the whisker ones). FrSky claims they provide an additional 20% range increase (or 20% stronger signal, if you like) over the standard antennas. I think your experience with the X6R compared to mine on the X8R tends to validate this.
I DID happen to log the whole flight, and it is quite interesting, in the nerdiest of ways. I also had an airspeed-sensor on board, and coupled with my wife's ground-video (where you can hear the announcer), I was able to graph RSSI and KIAS, and label the different portions of the flight.
During the pre-launch phase RSSI levels are normal; ~84dB. When Flight-4 launches there's nothing really dramatic, but there is a slight down-trend when Flight-3 launches; ~80dB. As F2 and F1 go up the downward trend increases; ~75dB after F2, ~70dB after F1. It stays right around that level during the "Official Minute", ~73dB. Inversely, you can see the levels come back up slightly as the flights land when the minute is over.
Science FTW!
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