On February 1, 1995, a Bell 47G-4A (registration N6SR) was involved in an aviation accident near EL Indio, TX. Investigators recorded the probable cause as: A right quartering tailwind gust caused the helicopter to lose tail rotor effectiveness. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A helicopter at 25 feet above ground lost tail rotor effectiveness due to a right quartering tailwind gust while chasing a bobcat. The helicopter spun right, pilot inputs led to main rotor RPM droop, and it impacted terrain.
Introduction
A helicopter engaged in predator control operations experienced a loss of control at low altitude. The aircraft was flying at approximately 25 feet above ground level while pursuing a bobcat.
Sequence of Events
According to the pilot, a right quartering tailwind gust caused the helicopter to lose tail rotor effectiveness. This resulted in the helicopter beginning to spin to the right. In an attempt to regain airspeed, the pilot increased collective and throttle. However, this action caused the main rotor RPM to droop. The altitude was insufficient to allow the helicopter to regain airspeed by lowering the nose. The pilot then reduced collective to regain RPM, but the helicopter continued to spin and subsequently impacted the terrain.
Outcome
The helicopter impacted the terrain following the loss of control. No further details on injuries or damage are available from the source.
Probable cause
A right quartering tailwind gust caused the helicopter to lose tail rotor effectiveness.