[rotorwrench]

Density altitude make sense. It must have been hot and humid that day. It's always that way down here so a person can't forget about it. In airplanes you need a longer runway. In helicopters you have to get moving into the wind and avoid downwind slow flying or hovering. Sometimes a pilot has to drag the skids for a while to get it up depending on how much power is available and how much lift the rotor can generate. The old Bell 47G with the early Franklin engine was that way.