WPR11LA352 · Eurocopter AS 350 B3
Air Methods Eurocopter AS 350 B3 · Accident: part(s) separation from aircraft en route
From Aurora State Airport (UAO) to DLS · Dallesport, WA
Event
- NTSB case
- WPR11LA352
- 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
Eurocopter AS 350 B3
- Aircraft type
- Eurocopter AS-350
- 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
- N808LF
- Operator
- Air Methods
- Onboard fatalities
- Unknown
- Route
- From Aurora State Airport (UAO), Aurora, ORTo DLS · Dallesport, 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
- 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
- Part(s) separation from aircraft
- 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
- Aircraft › Aircraft structures
- Personnel issues › Action/decision
- Personnel issues › Task performance
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot reported that, about 12 minutes into a repositioning flight following a maintenance task performed by a company mechanic, he felt something that he described as similar to a bird strike. The pilot subsequently elected to make a precautionary landing in order to assess the situation. During an examination of the helicopter after the uneventful landing, the pilot discovered that a portion of the tail rotor drive shaft cover was missing and that one main rotor blade and two tail rotor blades had been damaged. Postaccident discussions with the company’s director of maintenance determined that the maintenance staff (who had recently performed a maintenance inspection) and the pilot likely looked at the tail rotor drive shaft cover prior to the accident flight and presumed that it was secure or had been secured by someone else; however, it was not secure and came off during flight. Following the accident, the company implemented a primary mechanic position into its Field Mechanic Procedures in order to mitigate a similar occurrence.
Probable cause
The in-flight separation of the tail rotor drive shaft cover as a result of maintenance personnel not ensuring that it was secured after a maintenance inspection; also causal was the pilot’s inadequate preflight inspection of the helicopter.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR11LA352
- Event ID
- 20110729X63202
- Case number
- WPR11LA352
- 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: 8b875e8a110c9cda25f5d7a2fbdc6e9889234b515e43aa4bed84b54787d66712; retrieved 2026-09-15T16:32:02.056Z.