The pilot is sat considerably forward of the mast and therefore "enjoys" a ride on a centrifuge. Thrown forward and sideways, with a G loading dependent on the rate of spin and the arm, he may not have been conscious after the initial contact between head / airframe.
As to what to do: would it be possible to use the fire truck to soak the engines and cause a flameout? Likely to be difficult enough with the machine stationary but would have the side effect of reducing fire risk.