CEN13LA321 · Bell 206-L4
T & M Aviation Bell 206-L4 · Accident: part(s) separation from aircraft while maneuvering
From Abbeville Chris Crusta Memorial Airport (KIYA) to Abbeville Chris Crusta Memorial Airport (KIYA)
Event
- NTSB case
- CEN13LA321
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Bell 206-L4
- Aircraft type
- Bell 206
- Category
- Helicopter
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N720RL
- Operator
- T&M Aviation
- Onboard fatalities
- Unknown
- Route
- From Abbeville Chris Crusta Memorial Airport (KIYA), Abbeville, LATo Abbeville Chris Crusta Memorial Airport (KIYA), Abbeville, LA
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Maneuvering · hover
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Part(s) separation from aircraft
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Personnel issues › Task performance
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The helicopter was on its first flight after extensive maintenance. As the pilot approached a canal at an altitude of about 20 feet, he heard a noise and then a loud "pop." The helicopter then started to spin to the right and the pilot was unable to stop the spin. After about two revolutions, the pilot reduced engine power to idle, and the helicopter collided with terrain and water.
Examination of the helicopter revealed that the connection between the tail rotor drive shaft and the tail rotor gear box was partially separated. Of the two bolts that connected the drive shaft to the coupling on the gear box, one remained secured by its associated nut; however, the other bolt had backed out of the drive shaft, but remained in the coupling, and its corresponding nut was missing. The helicopter had accrued about 0.7 flight hours since its most recent maintenance, which included removing and reinstalling the tail rotor gear box. It is likely that the maintenance personnel did not ensure adequate torque of a tailrotor drive shaft coupling bolt, which allowed it to be back out of the drive shaft.
Probable cause
Failure of maintenance personnel to ensure adequate torque of a tailrotor drive shaft coupling bolt, which resulted in the partial disconnection of the drive shaft.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CEN13LA321
- Event ID
- 20130606X65516
- Case number
- CEN13LA321
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: d1bfd21b5a5832747bcbc5aa127f6606fd40470a45fc56bc78bbe38214300f06; retrieved 2026-09-15T21:48:10.540Z.