In this video posted by Truth Tracker in 2017 - 2018 (posted a couple of times by my memory) he narrator demonstrates by using freely available radar data how a helicopter "went dark" just before the 10-1-2017 shooting. Again this is a sloppy way to run an op, not considering that anybody with a laptop could unravel what they have done. But then again aren't they all sloppily run exercises?