Enstrom F28 N5691Y accident near Bridgeville, Delaware

Probable cause

The pilot's mismanagement of collective pitch control during takeoff from an area with numerous obstacles, which resulted in the helicopter entering a low rotor rpm state and a forced hard landing.

NTSB analysis

The commercial pilot had performed numerous local sightseeing helicopter flights the day of the accident. During the accident flight lift off from the field with power lines and farm equipment nearby, the pilot increased the throttle to the maximum engine and rotor rpm and began a climbing left turn toward power lines, during which he noticed the rotor rpm slowing. He slightly decreased collective pitch and further increased the throttle, but the rotor rpm did not increase. The pilot then increased collective pitch even farther as the helicopter cleared the power lines, which exacerbated the low rotor rpm state and was contrary to guidance published in the helicopter's pilot's operating handbook. The pilot's power management allowed the rotor rpm to decay below a point at which sustained flight was possible. Subsequently, the helicopter descended and impacted an open field hard, which resulted in substantial damage to the tailboom and tail rotor. The pilot did not report any preimpact mechanical malfunctions or failures with the helicopter, which was confirmed by a postaccident examination and test run of the helicopter's engine. The pilot's mismanagement of collective pitch control led to the helicopter entering a low rotor rpm state and its subsequent inability to maintain flight.

Text from the NTSB. Open the NTSB docket for ERA19TA005 for the full record.