ERA11IA320 · Robinson Helicopter Company R22 MARINER
Robinson Helicopter Company R22 MARINER · Incident: system/component malfunction/failure (non-power) en route
From Kingston-Ulster Airport (20N) to Martha's Vineyard Airport (MVY)
Event
- NTSB case
- ERA11IA320
- 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
- Incident
- 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
Robinson Helicopter Company R22 MARINER
- 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
- N8313E
- Operator
- Shevah Avi
- Onboard fatalities
- Unknown
- Route
- From Kingston-Ulster Airport (20N), Kingston, NYTo Martha's Vineyard Airport (MVY), Vineyard Haven, MA
- 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
- 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
- System/component malfunction/failure (non-power)
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- None
Cause areas
- Aircraft › Aircraft propeller/rotor
- Personnel issues › Task performance
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot stated that he felt an abnormal vibration in the helicopter during cruise flight. He performed a precautionary landing to residential driveway. Postincident examination revealed that the tail rotor teeter hinge bolt had fractured completely due to fatigue and that there was no torque stripe on the bolt to help identify possible movement. The manufacturer’s preflight inspection checklist required the pilot to verify that the tail rotor teeter hinge bolt does not rotate. When asked about preflight inspections, the pilot stated that he does not always use the manufacturer's preflight checklist. Maintenance records show that the most recent annual inspection was performed about 4 weeks before the incident. According to the manufacturer's maintenance procedures, during an annual inspection, a mechanic should verify that the tail rotor teeter hinge bolt remains stationary when teetering the hub. Also, it is recommended that a mechanic applies a torque stripe to the bolt. In addition, the maintenance manual contained an unboxed warning message about the importance of the correct installation of the tail rotor to prevent a failure of the teeter hinge bolt and loss of the tail rotor.
Probable cause
The pilot's inadequate helicopter preflight inspection and the mechanic’s inadequate annual inspection, both of which failed to detect a worn bolt in the tail rotor teeter hinge prior to its fracture due to fatigue.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ERA11IA320
- Event ID
- 20110601X42124
- Case number
- ERA11IA320
- 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, damage. 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: 9888c1a03e1bd101a386c5752c8161e2539e27631fd2d82575a320a53be5f029; retrieved 2026-09-15T16:13:58.167Z.