There is little strap showing at the top of the unit, so the angle is greater than 90*... very easy to overload a strap in that case. Not good considering plenty of picks I have been on have used questionable rigging (you know, those red telltales showing at the looped end of the strap).
Crane was way too short, but that isn't the cause of the unit falling down.
Poor rigging. With that kind of angle on the straps at least one of them had to be pulling on the safety catch on the hook. Bet the catch failed and every thing else failed. The operator shoud have never raised that in the air. If OSHA was to investigate that the crane company would loose. All so there is no tag line ties to the unit that is another no no.
wholy mackeral what a calamity did any one get hurt besides the embarrasment of the rigger?? Reminds me of the time i was being lazy while doing a 30 hp cast iron compressor changeout using a crane and just screwing in 2 'I' bolts in the top of the compressor with a short choker. Gave the operator the go ahead & turned around to hoof it up to the roof and heard a kid yelling to get out of the way , well that .comp. took a kamakazee dive right where i was standing. It smashed the concrete square and its oil pump and almost my little bald head!!!!!!! Turns out the lifting hooks were cast metal rated at 3 times the weight of the pump BUT , could not stand to be pulled any way but straight up. Should have used forged steel bolts and a safety choker , Lesson learned the hard way. Boss didn't bat an eye , ordered a replacement , finished the job & all that was said was next time use the right bolts & bought lunch & never heard about it again because i was hard enough on myself . , Jack
Last edited by rojacman; 05-11-2008 at 10:45 PM.
Reason: added thought