NYC01LA059 · Aerospatiale SA365-N1
Corporate Jets Aerospatiale SA365-N1 · Accident: airframe, component or system failure en route
From Allegheny County Airport (AGC) to Pittsburgh, PA
Event
- NTSB case
- NYC01LA059
- 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
Aerospatiale SA365-N1
- Aircraft type
- Aerospatiale SA365
- 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
- N89SM
- Operator
- Corporate Jets
- Onboard fatalities
- Unknown
- Route
- From Allegheny County Airport (AGC), Pittsburgh, PATo Pittsburgh, PA
- 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
- 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
- Airframe, component or system failure
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Cause areas
- Company maintenance personnel › Maintenance, lubrication, low
- Pilot in command › Airspeed, not maintained
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The pilot stated he that performed a pre-flight inspection, checked the fluids, and ensured that the cowlings were closed and secured prior to conducting the helicopter's post-maintenance track and balance flight. In flight, after conducting several maneuvers, and while the helicopter was flying straight and level at 120 knots, the pilot noticed he had no anti-torque pedal control. He declared an emergency, and attempted numerous approaches to two different runways. Every time the helicopter slowed to 80-100 knots, the nose would swing to the left. During the final approach, while nearing touchdown on the runway, the pilot added collective, and the helicopter climbed while spinning to the left. The pilot reduced power, and the helicopter descended to, and impacted the ground while still in a left spin. Post-accident examination revealed that the bellcrank fitting at the tail servo input was broken, and there was very little oil in the tail rotor gearbox. There was no evidence of oil leakage at the seals or the filler cap. A small amount of oil was recovered, which was black in appearance. The oil level sight gage was marked with a black line, 6 to 7 mm below the minimum fill level. The output drive shaft duplex bearing displayed no evidence of lubrication. The inner races of the duplex bearing were removed and one displayed signs of wear and heat damage. The outer races contained metal transfers similar to the bearing cage, and the duplex bearing was seized. The flight manual did not contain any emergency procedures for a stuck (fixed pitch) tail rotor.
Probable cause
Insufficient lubrication within the tail rotor gearbox, which resulted in the seizure of the duplex ball bearing and a fixed pitch setting of the tail rotor. Also causal, was the pilot's loss of control, which was the result of a relative low speed/high power combination during a go-around attempt. A factor was the manufacturer's lack of procedures for fixed tail rotor pitch settings.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record NYC01LA059
- Event ID
- 20010105X00048
- Case number
- NYC01LA059
- 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: 4842d6379a75ad06382855eea35a16bb61351d1fc263be526c99363a21834372; retrieved 2026-09-21T10:17:45.754Z.