I should have more carefully heeded Comrade Johnson-Laird's admonitions. When I configured my mx-20, I assigned Carefree mode to a switch on the transmitter. I haven't used it yet, as I'm actually quite a bit better at controlling my Cinestar 8 than I thought I would be. I guess all that time with my Xpro Heli XP2 quad paid off! Today I put together my FPV rig and took it out to do some testing. I left an LCD monitor in the back of my car with a GoPro pointing at it, ostensibly to "watch" the display for any dropouts, etc. I just wanted to get a sense of the range, etc. I was flying around my regular park, where I have about 400 meters of open space, bounded by large (100+ foot) Eucalyptus trees. The FPV tests appeared to be going well, based on a few peeks I made back at the display whilst flying about, and when I turned on GPS position/altitude hold. But on about my 5th or 6th sortie, something went horribly wrong. I started out flying normally, but then I seemed to lose control of the bird in a very trivial situation...just hovering 30-40 feet above where I was standing. The sticks seemed to be all confused. And before I knew it, I was flying backwards at a high rate of speed into a stand of the aforementioned Eucalyptus trees. Suffice it to say I had to drive back to my studio and fetch my 40' extension ladder to fetch the bird out of the tree. I tied it to a rope and lowered it down to the ground. Remarkably, its only damage was a broken propellor. And the little LiPo that was powering the FPV rig was completely dead by the time I got up there. The mains LiPo was fine. And the landing gears were tweaked, but I keep them loose, so they just rotated back into position. I was reviewing the flights over and over in my mind as I was shooting a gig tonight, and it finally dawned on me: I must have accidentally engaged Carefree mode. When I got home I looked over the telemetry, and that's exactly what happened. I must have bumped the switch and even though I was using voice telemetry, when I have "REPEAT" turned on, it misses some of the messages. Sigh. Guess what I'm doing tomorrow morning after I replace the broken prop? And my underwear?