What happened
During a takeoff maneuver, a helicopter experienced a sudden, momentary partial loss of engine power. The pilot reported that all instruments initially indicated normal operations, and the aircraft departed with a normal rate of climb. However, the loss of power caused the aircraft to descend rapidly toward a parking lot containing several vehicles.
Because the aircraft was at an insufficient altitude to adjust the collective to minimize power applications, the pilot was unable to avoid an impact. The helicopter struck both the terrain and vehicles in the parking lot, resulting in substantial damage to the aircraft. The pilot and two passengers sustained minor injuries during the event.
A witness on the ground observed the pilot nosed the helicopter over to gain forward momentum and altitude, noting a distinct change in the sound of the engine during the departure.
The investigation
As part of the investigation, the engine was subjected to a test run. The testing confirmed that the engine produced its full rated power.