I have 2 P3P batteries. Last week after installing clip-on prop guards, I was flying at 5 feet and walking behind the bird slowly going forward, when all the sudden the power went off and it flipped upside down. No damage. I've been very careful with charging - always a cool battery, have not let it get below 45 percent. 68% at crash time. Today, same thing happened again with 65% left, only from about 25 feet up while hovering in place - no stick input - when all the sudden it stopped, flipped forward and landed upside down in 4 inch grass. The video in both incidents just stopped - the last frame showed the shot I had been going for, then nothing. No crash footage. One prop guard broken, otherwise no damage - powered back up fine and camera reset correctly. This was the same battery that was in the previous incident. It had a pink gaffer tape identifying it as Batt #1. I've always been careful to listen and feel for a full click when snapping in the battery - even more so after the first failure. Any history of this kind of stuff happening with Phantom batteries? I won't be using #1 again until we figure this thing out.