FTW04LA067 · Bell 206-L4
Bell 206-L4 · Accident: in flight collision with object en route
From SP-10, GM (no airport) to Harry P Williams Memorial Airport (PTN)
Event
- NTSB case
- FTW04LA067
- 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
- Charter & commuter
- 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
- N207RT
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From SP-10, GM (no airport)To Harry P Williams Memorial Airport (PTN), Patterson, 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 135: Air Taxi & Commuter
- 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
- En route · cruise
- First occurrenceThe 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
- In flight collision with object
- 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
- Loss of tail rotor effectiveness
- Pilot in command › Autorotation, performed
- Pilot in command › Directional control, not possible
- Wing, winglet › Cracked
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The 10,300-hour pilot reported that while in cruise flight at an altitude of 500 feet and 110 knots, he heard a "loud" bang followed by "severe" and constant vibration. He stated that the pedal inputs "seemed" to have no effect in correcting the yawing of the aircraft. It was apparent to the pilot that continued flight would be impossible, and he elected to perform a forced landing. The pilot began a 180-degree autorotation to the left. While in the turn, the pilot made a "mayday" call, and reduced the throttle, which had no effect. Once the pilot closed the throttle, the "pounding and vibration" lessened. After the aircraft rolled out, and was level at 100 to 150 feet, the pilot realized they were going to hit the levee of the pond. He pulled a little collective to clear the levee, performed a cyclic turn to the right, and cushioned the landing. When the helicopter landed, the main rotor blade contacted the tailboom. Examination of the wreckage by the operator and a FAA inspector, who responded to the accident site, revealed structural damage to the tailboom. Strike marks on the tailboom, corresponding to the main rotor blade top path plane, were found adjacent to the #7 tail rotor drive shaft segment. Additionally, the left horizontal stabilizer winglet device was not found. Further examination revealed a ten-inch crack in the fixture securing the left winglet to the horizontal stabilizer. The right winglet, which was found, also had a pre-existing crack in the same area. The cracks were not visible during a visual inspection, and the crack area is under a line of structural adhesive used during manufacture of the horizontal stabilizer, and can only be seen when the winglet is removed. According to the operator, the 10-inch crack that was discovered on the left winglet appeared to have existed for some time. The operator stated that the winglet could have separated from helicopter in-flight, and struck the tail rotor, resulting in the "loud bang" that was heard by the pilot, and subsequent loss of directional control.Other than the winglet, examination of the helicopter, and its drive and flight control components did not reveal any pre-existing anomalies that could have contributed to the accident.
Probable cause
The in-flight separation of the helicopter's left winglet due to pre-existing cracks resulting in the winglet striking the tail rotor in-flight, and subsequent loss of directional control.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record FTW04LA067
- Event ID
- 20040203X00148
- Case number
- FTW04LA067
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
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, coordinates. 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: 7bc3e8141649da8d258aae0d1e63511e303a1cc59ee61f6e2ebf9e4edc36f4e3; retrieved 2026-09-18T15:30:48.916Z.