This happened when one of our new guys took too many wraps and locked the rope up. The intial shockload did what you see. The pulleys side plates are rated at 16,000lbs, just to give you an idea of the force behind it.
I finally saw the photo that someone posted on the Treebuzz and I agree with them that the gear (pulley) was not rated for the load that it was carrying. Also the metal-link was not closed properly. I think they called that one \"operator error\". Luckly nobody was injured. Select the proper gear next time. This is probably better posted in the \"Professional Workers Area\".