Primary finding
Probable cause
The pilot's failure to properly monitor power required versus power available to maintain rotor revolutions per minute (rpm), resulting in rotor rpm decay and a forced landing. Factors related to the accident were: the pilot's change of the tour route without notifying the company, which delayed rescue, and the location of the arm and fire switches for the flotation equipment, which required the pilot to remove his hand from the collective control to activate that equipment.