In Episode 7 of The Secret of Skinwalker Ranch, a suspicious helicopter is spotted flying over the ranch. Despite having binoculars they failed to identify it, and said it did not show up on the ADS-B scanner.
[Update] I contacted Corporate Helicopters. Ivor Shier, the director of operations, called me back and confirmed it was their helicopter and that they were just doing a LIDAR powerline survey. This is looking for things like defects in insulators and encroaching vegetation – anything that might be a fire hazard. He said that’s all it was. He said they don’t turn off the ADS-B ... Read even more