Bell 206 N106PD accident near Blair, Nebraska

Probable cause

The loss of main rotor rpm for reasons that could not be determined based on the available evidence, which resulted in a hard landing.

NTSB analysis

The pilot-in-command (PIC), who is also a flight instructor and was stationed in the right seat of the helicopter, decided to conduct emergency procedure training with a simulated governor failure of the turboshaft engine before returning to the airport to land. The co-pilot, who is not a flight instructor, was stationed in the left seat. The intent was to recover from the simulated governor failure at a safe airspeed and altitude. The PIC initiated a simulated governor failure by rolling the throttle down just enough to take the governor offline but still maintain the main rotor rpm in the green (normal) range. The helicopter descended while maintaining airspeed until over the runway. About 40 ft above ground level and about 45 knots, the PIC announced his intention to complete the training maneuver and rolled the throttle back to the full open position. The PIC verbally confirmed the main rotor rpm indication in the green range. All other indications in the helicopter appeared to be normal to the PIC.

As the helicopter was in normal operating conditions, the PIC applied aft cyclic to slow down and begin air taxiing to the parking pad to the east (right) of their current position. At that moment, he heard the low main rotor rpm audible horn. The PIC confirmed a loss of engine power by referencing indications in the cockpit. The helicopter descended very rapidly toward the ground and the PIC surmised the engine was unable to produce power. The PIC reduced the collective briefly to regain main rotor energy then applied collective to cushion the landing. The helicopter impacted the runway and came to rest on its left side, which resulted in substantial damage.

A postaccident examination of the airframe and engine revealed no preimpact mechanical malfunctions or failures that would have precluded normal operation. Based on the available evidence, the loss of main rotor rpm could not be determined.

Text from the NTSB. Open the NTSB docket for CEN19LA269 for the full record.