Phantom Down! Video Analysis: At 10:00 I received a low-battery alert and paused to assess the situation. Battery level indicated 58%. I normally receive the first low battery warning ~15 minutes into a flight. I noticed she was beginning to descend and applied full throttle to maintain altitude. This slowed the descent rate but did not halt it completely. Unfortunately the vantage point from my house is surrounded by trees and I need altitude to maintain line of sight, particularly to the south where the bird was located. I was barely above the treeline when this situation occurred and, as she slipped out of sight, I also lost FPV. I initially engaged Home Lock and started bringing her home but, as she slipped out of sight @ 11:00, I was flying blind and just guessing how she was responding. At around 12:00 I finally concluded it was best to let her auto-land straight down. At least I would have a location fix where I could mount a recovery operation, rather than her coming down along the way where I would have no idea where to begin a search.
She settles gracefully atop the forest canopy @ 14:22, and the motors continue to run until the battery expires @ 19:35. This is when she must have rolled over and nestled in among the branches. Not sure why the motors continued to run after she touched down unless she was attempting to return home? No way to tell as In the video the rear LEDs are drowned out by the red navigation LEDs up front. Too bad the motors didn't shut down. She may have remained powered on for another 30 minutes or more with only the electronics drawing power. I may have arrived in time to spot the LEDs in the trees. Watching the gentle landing its easy to see why she suffered no physical damage.
In retrospect it was over 4 minutes from the low battery alert until she settled into the treetops. From my vantage point, her rate of descent appeared to be much faster. I probably could have made it back if only I could have maintained visual or FPV! :roll:
Phantom Down! Video - Full Flight
[youtube]https://www.youtube.com/watch?v=6rtMe_RvNck[/youtube]