SEA03LA156 · Hughes 269C
Hughes 269C · Accident: partial loss of engine power (mechanical failure) while taxiing
From Skagit Regional Airport (BVS) to Marblemount, WA
Event
- NTSB case
- SEA03LA156
- 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 269C
- Aircraft type
- Hughes 269
- 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
- N500HS
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Skagit Regional Airport (BVS), Skagit Regional, WATo Marblemount, 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
- Taxi · aerial
- 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
- Partial 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
- Ignition system, magneto › Failure, partial
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
Once he arrived in the area of the lake where he was planning on camping, the pilot made two high reconnaissance passes in order to look the area over before descending to a lower level so he could take a closer look at possible camping sites along the lake's edge. The pilot completed a systems flow check prior to initiating a hover taxi over the lake, and then once the hover was established, the oil pressure and oil temperature was rechecked. The pilot then began "hovering down the middle of the lake," looking at possible landing sites, but ultimately, when he reached the far end of the lake, he decided that the best spot was at the other end where he had first passed over the shoreline. Just about the time he was getting ready to turn back, he noticed a gradual drop in engine rpm's, and the aircraft began to slowly descend toward the surface of the lake. Although he increased the throttle, he was unable to increase or stabilize the rpm, and the helicopter eventually settled into the water in a level and upright position. The rpm had initially been 3,200, but by the time the aircraft touched the surface of the water it had dropped to 2,400. Ultimately the aircraft came to rest upright on its skids in about six to eight feet of water, but the main rotor blades were damaged when they contacted the water's surface. As part of the investigative process, the older left magneto was removed from the aircraft and tested at various rpm’s (the right magneto was newly installed, and not removed for testing). During the subject testing, the left magneto performed erratically, and did not produce a consistent continuous spark at high rpm's. After the testing was terminated, the magneto was disassembled and inspected, but the specific reason for its inconsistent performance was not able to be determined.
Probable cause
The partial failure of a magneto during hover taxi over water, leading to a forced landing in shallow water near the shoreline. Factors include the aircraft being over a lake at the time that the partial loss of power made it impossible to keep it airborne.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record SEA03LA156
- Event ID
- 20030730X01226
- Case number
- SEA03LA156
- 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: local date, investigation status, coordinates. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 2003-07-25.
- API snapshot SHA-256: 2723a2983df399f7be24830f1727d32787f37e15b2454f3780d813255a057b24; retrieved 2026-09-22T08:53:41.695Z.