On August 1, 1990, a Bell 47G-3B-1 (registration N34691) was involved in an aviation accident near Hanson, MA. Investigators recorded the probable cause as: The loss of tail rotor control due to the shearing of the tail rotor drive shaft between the number 5 and number 6 bearings. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A helicopter lost tail rotor control while flying at 100 feet during aerial application, resulting in a slow spin and ground impact due to a sheared drive shaft.
What happened
The pilot was conducting aerial application activities when the incident occurred. At the time of the event, the helicopter was operating approximately 100 feet above the ground. During this phase of flight, there was a sudden loss of tail rotor control. Following this mechanical failure, the aircraft entered a slow spin and subsequently descended into the ground.
The investigation
A post-accident examination of the wreckage revealed significant mechanical damage to the tail rotor system. The inspection determined that the tail rotor drive shaft had been sheared off. This structural failure occurred specifically between the number 5 and number 6 bearings within the assembly.
Probable cause
The loss of tail rotor control due to the shearing of the tail rotor drive shaft between the number 5 and number 6 bearings.
Frequently asked questions
What happened in the 1 Aug 1990 Bell 47G-3B-1 accident near Hanson, MA?
A helicopter lost tail rotor control while flying at 100 feet during aerial application, resulting in a slow spin and ground impact due to a sheared drive shaft.
What aircraft was involved and where did it happen?
The accident on 1 Aug 1990 involved a Bell 47G-3B-1, registration N34691, at Hanson, MA.
What was the probable cause of the accident?
The loss of tail rotor control due to the shearing of the tail rotor drive shaft between the number 5 and number 6 bearings.
A SkyWalk Join't 3 paraglider crashed into the ground near Las Vizcachas, Chile, on September 1, 2024. The pilot and passenger sustained serious spinal…
PARAPENTE (ULTRALIVIANO NO MOTORIZADO)·2024-09-01DGAC Chile
A Cessna 172N struck electrical cables while on final approach to land at Aucó Aerodrome in Chile. The pilot was uninjured, but the aircraft sustained damage…
A Bombardier DHC-8-402 suffered a tail strike during landing at Puerto Williams on September 9, 2024. All 76 occupants were unharmed, but the aircraft…
A MYD JS-MD 3 glider veered off the runway and struck a wall at Vitacura Aerodrome on January 6, 2025. The pilot was uninjured, but the aircraft sustained…
A recreational paraglider flight in Puchuncaví, Chile, ended with the pilot sustaining serious injuries after a rapid descent and impact with a hillside on…
PARAPENTE (ULTRALIVIANO NO MOTORIZADO)·2025-03-29DGAC Chile
A Tecnam P2006T landed on its belly at an aerodrome in Poland after the crew failed to confirm landing gear deployment. The incident resulted in no injuries…