LAX00FA306 · Robinson R22 BETA
Robinson R22 BETA · Accident: rotor failure/malfunction
From Watsonville Municipal Airport (WVI) to Watsonville Municipal Airport (WVI)
Event
- NTSB case
- LAX00FA306
- 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
- 2 · all aircraft and ground
- Ground fatalities
- 0
- 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
Robinson R22 BETA
- Aircraft type
- Robinson R22
- 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
- N8313Z
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Watsonville Municipal Airport (WVI), Watsonville, CATo Watsonville Municipal Airport (WVI), CA
- 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
- Unknown
- 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
- Rotor failure/malfunction
- 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
- Rotor system, main rotor › Diverged
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The flight instructor was cruising or maneuvering the helicopter during an introductory flight with a new student. Witnesses in the area reported observing the helicopter in what appeared to be normal flight, heard a loud bang, and then saw the helicopter abruptly pitch nose down while the main rotor blades separated from the helicopter. One of the witnesses observed the helicopter turn and climb moments before the accident sequence initiated; two of the witnesses reported that just prior to the accident the helicopter was flying in level cruise flight. At the time of the accident, the sky was clear, the visibility was at least 10 miles, a light breeze existed, and no other aircraft were flying in the immediate area. The on-scene examination of the accident site revealed Plexiglas fragments and left door components about 400 feet from where the main wreckage fell into an open dirt field. Additional items, including sunglasses, a left skid tube-mounted component and the main rotor blade assembly, were found 140 to 330 feet from the main wreckage. An examination of the rotor hub revealed the teetering stops were cracked and both of the rotor blade spindles had broken their respective (droop stop) tusks. The physical evidence indicates the main rotor diverged from its normal plane of rotation, resulting in mast bumping, main rotor blade contact with the fuselage, and separation of the main rotor assembly. No evidence of any preimpact mechanical malfunction was found with the helicopter. The initiating event that produced the main rotor divergence could not be determined.
Probable cause
The divergence of the main rotor from its normal plane of rotation for an undetermined reason, which resulted in mast bumping and rotor contact with the fuselage.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record LAX00FA306
- Event ID
- 20001212X21753
- Case number
- LAX00FA306
- 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: local date, investigation status, coordinates. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 2000-08-19.
- API snapshot SHA-256: 049ad6e3ca2b310bd16c7ede5f447674ee47adb5061d46db2c8c9c0a2324c403; retrieved 2026-09-20T20:55:12.194Z.