IRIS first gen with gimbal dropped twice last week

Hey all, I am hoping to get some log analysis help. I have spent some time looking at it but am not sure what to make of the data.

Normally I do not have any problems with my copter and have been very happy. I am working a weekly dam job and the thing has dropped twice on me now. Once in autopilot and once in manual flight mode.

1st drop: I had already completed a successful mission. Put in new battery and new mission to get the second run needed for the job. It flew for about 5 or 6 minutes and followed its path perfectly. At a certain point, it seems to stop and hover in between waypoints. We noticed the change in behavior and then it appeared to get back on course. Shortly after that it just lost elevation and stuck in the trees. I have been having some issues with my controller beeping at long distances, but I don’t see a failsafe enabled.

2nd drop: 3 days later after some minor prop repairs etc from the 1st crash, it did the same thing. I was flying for about 5 or 6 minutes manually and then for no reason I know of, it just started loosing altitude until it hit the ground. I pushed throttle all the way up but it did not respond to my command.

Both times i tested the battery afterward and they were never even below 50% capacity. All fairly new batteries.

It would be greatly appreciated if someone could look at my log and help me understand what happened or what I should look for. I read the faq for this forum but I am still at a loss. The barometer seems to get wonky. It does not drop like a rock, it simply stops responding and descends to the ground.

Link to the BIN file: drive.google.com/open?id=0B0Icy … kZDVkFQX0k

Many thanks,
Charles