WPR10LA336 · Johnson HELICYCLE
Johnson HELICYCLE · Accident: hard landing during autorotation
From Arlington Municipal Airport (AWO) to Arlington Municipal Airport (AWO)
Event
- NTSB case
- WPR10LA336
- 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
Johnson HELICYCLE
- Aircraft type
- Johnson HELICYCLE
- 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
- N62AJ
- Operator
- Johnson Alden B
- Onboard fatalities
- Unknown
- Route
- From Arlington Municipal Airport (AWO), Arlington, WATo Arlington Municipal Airport (AWO), Arlington, WA
- 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
- Autorotation
- 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
- Hard landing
- 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
- Not determined › Not determined
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot reported that after an uneventful flight, he entered a left downwind traffic pattern for his intended landing area. As he lowered the collective to initiate a descent, he immediately experienced a severe vibration. The pilot stated that the vibration was so violent that it was impossible to read the cockpit instruments. He raised and lowered the collective and noted no change in the vibration. The pilot then initiated an autorotation to an open field adjacent to his intended landing area. The helicopter landed hard and came to rest upright. A postaccident examination of the helicopter revealed that the tail rotor was separated from the tail boom with additional damage observed to the fuselage and main rotor blades. Flight control continuity was established throughout the helicopter's flight control system. The source of the vibration could not be determined.
Probable cause
An undetermined airframe vibration which led to precautionary autorotation and hard landing.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR10LA336
- Event ID
- 20100708X70842
- Case number
- WPR10LA336
- 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: 4f7a5fc182ad148b667c5c1e097492110ec45c0e6a17aa062d337c47092cf6fb; retrieved 2026-09-15T14:39:39.486Z.