Back in the 80's we were setting large HVAC units on top of a new building with the use of a helicopter. One unit was too heavy and we brought in a huge crane from out of town. He set up the unit in the mud ( it was pouring rain ) and began to lift the unit. My partner and I were just walking up to the unit to spin it around to match up with the platform it would sit on. The unit was still about 5 feet above our heads when the crane began to settle in the mud and the operator released the cable and the load to save the crane. It dropped right in front of our eyes within a few feet of us. The operator told us afterwards he had to make a decision of letting the crane fall on our heads or the HVAC unit. My opinion, the operator failed to consider the conditions he was settling the crane up in (mud) and was totally at fault. I never trusted another crane operator after thet. We have had numerous crane accidents within a few miles of this town, it happens way too often! gj
Below is a picture of HVAC units being lifted by a helicopter which by the way is no more safer than the cranes I don't trust!!!