This one time-lol, when I was cleaning right aways about 10 yrs ago or more I was limping a skinny birch tree and I knew my chain was getting a little loose but I didn't wanna stop and tighten it, only a few trees left for the day, well I got a little twist in the blade, and if you've operated a saw much you know exactly what's gonna happen, I had the saw a little over chest height, and when it spit the chain it slapped me in the chest....however when they derail they usually get caught on the saw somehow and are not rotating, lucky me I just had a couple little scratches. Another time I was working next to the lead faller, he was still wasted from the half gallon the night before, he dropped a poplar on to a power line, it was super sketch, he said don't move! Let it burn through that line before you take one foot off the ground! It was crazy watching the tree trunk arc to the ground for what seemed like forever until it burned through the line.