On April 15, 2006, a Central Copters LANCAIR IV-P (registration N671) operated by Mark W. Duffy was involved in an aviation accident near Belgrade, MT. Investigators recorded the probable cause as: The quill shaft between the reduction gear box and the power section of the engine decoupled during final approach. 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.
During a night visual approach, the quill shaft between the reduction gearbox and engine power section decoupled, causing loss of propeller drive. The aircraft executed a forced landing on rough terrain, followed by a fire that consumed it.
Event Description
While on final approach for a night visual landing, the quill shaft connecting the reduction gearbox to the power section of the engine decoupled. This failure resulted in a loss of drive input to the propeller, leading to a forced landing off the airfield on rough and uneven terrain.
Landing and Post-Crash Sequence
The initial touchdown was successful; however, during the rollout, the aircraft impacted the terrain. After the aircraft came to a stop, a small fire developed near the engine exhaust. The occupants attempted to extinguish the fire but were unsuccessful. The fire eventually consumed the entire aircraft.
Probable cause
The quill shaft between the reduction gear box and the power section of the engine decoupled during final approach.
What happened in the 15 Apr 2006 Central Copters LANCAIR IV-P accident near Belgrade, MT?
During a night visual approach, the quill shaft between the reduction gearbox and engine power section decoupled, causing loss of propeller drive. The aircraft executed a forced landing on rough terrain, followed by a fire that consumed it.
What aircraft was involved and where did it happen?
The accident on 15 Apr 2006 involved a Central Copters LANCAIR IV-P, registration N671, operated by Mark W. Duffy, at Belgrade, MT.
What was the probable cause of the accident?
The quill shaft between the reduction gear box and the power section of the engine decoupled during final approach.
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…