SEA03LA021 · Hughes 369D
Pathfinder Helicopters Hughes 369D · Accident: total loss of engine power (mechanical failure) en route
From Boise Air Terminal/Gowen Field (BOI) to Boise Air Terminal/Gowen Field (BOI)
Narrative check · The NTSB narrative appears to contradict this record's flight rules. Values are shown as recorded, not corrected; compare with the narrative.
Event
- NTSB case
- SEA03LA021
- 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
Hughes 369D
- Aircraft type
- Hughes 369
- 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
- N8366F
- Operator
- Pathfinder Helicopters
- Onboard fatalities
- Unknown
- Route
- From Boise Air Terminal/Gowen Field (BOI), Boise, IDTo Boise Air Terminal/Gowen Field (BOI)
- 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 Possible conflict
- 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
- 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
- Total loss of engine power (mechanical failure)
- 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
- Check pilot › Flare, premature
- Company maintenance personnel › Maintenance, alignment, improper
- Pilot in command › Flight manuals, disregarded
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The commercial pilot, who had 900 hours PIC flight time in the make/model, and an FAA check pilot, who had 40 hours PIC flight time in the make/model, departed on a Part 135 check flight in the McDonnell Douglas (Hughes) 369D rotorcraft. After returning to the Boise airport, the commercial pilot (examinee in the left seat) transferred control of the aircraft to the check pilot (right seat) who then demonstrated a simulated 180-degree autorotation. After the check pilot rolled off power, the GEN OUT caution light illuminated followed by the ENG OUT warning light. The check pilot noted rotor RPM in the green but decelerating engine RPM, and the commercial pilot reported that he felt the check pilot's flare was premature. The rotorcraft landed hard during which time the main rotor blades flexed down impacting and severing the tailboom. Post-crash examination revealed that the left and right seat throttle/collective controls to the engine fuel control unit had been misrigged, and a test run of the engine confirmed a flameout condition when the right seat throttle was retarded to the idle position. A review of the rotorcraft's maintenance log showed that the right seat controls had been installed two days previous and signed off as "all rigging found to be within limits." The McDonnell Douglas MD500D Rotorcraft Flight Manual discusses throttle rigging in the Normal Procedures Section noting that a throttle rigging check must be performed prior to autorotation training, and the check must be performed on both left and right seat throttle controls if dual controls are installed. The Rotorcraft Flight Manual also provided a warning that "Misrigging of the throttle control may result in inadvertent flameout during rapid closing of the twistgrip to the ground idle position."
Probable cause
The failure of the operator's maintenance personnel to properly rig the left/right seat twistgrip throttles to the engine fuel control, the pilot in command's failure to adhere to the rotorcraft flight manual, and the check pilot's premature flare during the autorotation resulting in a hard landing.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record SEA03LA021
- Event ID
- 20021231X05648
- Case number
- SEA03LA021
- 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: investigation status, coordinates. 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: 2af4af598833581f394b3380e69972456bfec30da269026e69320e612b33f0f6; retrieved 2026-09-22T09:46:56.258Z.