On September 26, 1984, a Bell 206L-1 (registration N5013F) operated by Commercial Helicopters was involved in an aviation accident near West Delta 105. Investigators recorded the probable cause as: Frictional overheating and subsequent failure of the turbine inner shaft due to carbon buildup between the turbine-to-compressor coupling and the turbine inner shaft. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive; 1 related events involving the same aircraft type or operator are linked below.
A total power loss during cruise forced a pilot to execute an autorotative water landing with emergency floats. The aircraft rolled inverted because the right float failed to fully inflate upon impact.
What happened
During a cruise phase of flight, the aircraft experienced a complete loss of power. The pilot initiated procedures for an autorotative water landing and deployed the emergency flotation system. Upon touchdown on the water, the right float did not fully inflate. This failure caused the aircraft to roll to the right, resulting in an inverted position.
The investigation
A teardown of the engine was conducted to determine the root cause of the power loss. Examination revealed significant carbon buildup located between the turbine-to-compressor coupling and the turbine inner shaft. This accumulation caused frictional overheating, which ultimately led to the failure of the shaft.
Probable cause
Frictional overheating and subsequent failure of the turbine inner shaft due to carbon buildup between the turbine-to-compressor coupling and the turbine inner shaft.
What happened in the 26 Sept 1984 Bell 206L-1 accident near West Delta 105?
A total power loss during cruise forced a pilot to execute an autorotative water landing with emergency floats. The aircraft rolled inverted because the right float failed to fully inflate upon impact.
What aircraft was involved and where did it happen?
The accident on 26 Sept 1984 involved a Bell 206L-1, registration N5013F, operated by Commercial Helicopters, at West Delta 105.
What was the probable cause of the accident?
Frictional overheating and subsequent failure of the turbine inner shaft due to carbon buildup between the turbine-to-compressor coupling and the turbine inner shaft.
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…