On November 15, 1993, a Bell 47G3B1 (registration N1181W) was involved in an aviation accident near Mesa, WA. Investigators recorded the probable cause as: The pilot's failure to maintain proper airspeed during the final approach and an improper flare technique, which resulted in the tail rotor hoop contacting the ground and a subsequent hard landing that damaged the main rotor blades and tail boom. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A helicopter pilot maintained excessive airspeed while approaching the runway, leading to an improper flare and a hard landing that damaged the tail boom.
What happened
The incident occurred while the aircraft was on final approach for landing. The pilot allowed the airspeed to remain excessively high as the helicopter neared the ground. During the attempt to land with this surplus speed, the pilot executed an improper flare maneuver. This error caused the tail rotor hoop to strike the ground first, followed immediately by a hard landing of the main fuselage.
The investigation
The physical damage sustained by the aircraft was consistent with the described impact sequence. The force of the hard landing caused the main rotor blades to flex downward. As a result of this flexing, the blades cut through the top tubes of the tail boom structure.
Probable cause
The pilot's failure to maintain proper airspeed during the final approach and an improper flare technique, which resulted in the tail rotor hoop contacting the ground and a subsequent hard landing that damaged the main rotor blades and tail boom.