Soloy Helicopters Hughes 500D incident
Hughes 500D · Incident: loss of engine power (partial) en route
From McGrath Airport (PAMC) to McGrath Airport (PAMC)
Event
- NTSB case
- ANC11IA059
- 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
- Charter & commuter
- 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
Hughes 500D
- Aircraft type
- Hughes 500
- 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
- N315SH
- Operator
- Soloy Helicopters
- Onboard fatalities
- Unknown
- Route
- From McGrath Airport (PAMC), McGrath, AKTo McGrath Airport (PAMC), McGrath, AK
- 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 135: Air Taxi & Commuter
- 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 · descent
- 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
- Loss of engine power (partial)
- Also codedOther events the NTSB coded in the sequence, such as a wire strike after a loss of power. Flight Findings uses them for its kinds of event. Glossary
- Tree(s)
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Minor
Cause areas
- Aircraft › Aircraft power plant
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot reported that during a descent, the helicopter's engine sound changed abruptly and was immediately followed by the engine-out audio horn, and a red engine-out annunciator light. She entered an emergency autorotation, and then selected a mostly open area that contained some trees as an emergency landing site. During the emergency landing, the main rotor blades struck several small trees as the helicopter touched down on the uneven, tundra-covered terrain. A postincident inspection revealed a fatigue fracture in the engine Pc line that provided compressed air to operate the engine governor and fuel control units. The Pc line met the metallurgical material specifications, but there was a bend in a normally straight portion of the line, which would have placed stress on the Pc line when installed. The additional stress likely resulted in the eventual fatigue failure of the line. It could not be determined how or when the bend occurred.
Probable cause
A fatigue fracture of the governor-to-fuel control Pc line, which resulted in a partial loss of engine power.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ANC11IA059
- Event ID
- 20110708X15545
- Case number
- ANC11IA059
- 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: local date, investigation status. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 2011-07-05.
- API snapshot SHA-256: 99c84e9767957047130a515054cf4878ba900a2de72f21aa28a69568e16ced37; retrieved 2026-09-15T16:25:38.178Z.