Well, disaster was averted today thank God! I went out to Letchworth State Park in NY to get some video - was a beautiful day. Did all my preflight checks, calibrated compass and flew for a few minutes over land to make sure everything was working well. I started out using Litchi on my TabS2. After a few minutes the app crashed so I just restarted it and it connected again and flew fine - This has happened once in a while so I didnt give it to much concern. After the 2nd time I decided to bring it in. I landed, turned everything off and started over with DJI Go. I brought it over the middle of the falls and flew around taking some video. At this point Im around 350' above the water below the falls - I started bringing it toward me then everything went black. All of a sudden I was loosing control - I was able to get if flying toward me in manual control then she just dropped. I thought for sure she was gone and ran over to the stone wall. I looked over and saw her resting on her side on around a 1' ledge of grass. I cleaned her off and did a test flight over grass and everything seems fine I have no idea what happened but cant believe I have her home. Any incite or help would be greatly appreciated - FYI - Up till today I have never had any issues. Last week I did a cold IMU calibration and have flown since without issue. All lights were good, signal was good, compass was good - absolutely no signs of issues. I had the TabS2 on wifi and mobile data but there wasnt much cell coverage. I was connected to 16 satellites but in Healthydrones it showed my GPS signal as fair. Its one thing to have it fall and be able to send it back for repair but I was about an inch away from never seeing it again If/when a phantom drops from sky with no apparent reason is there anyway to diagnose?