ANC99LA114 · Cessna 206A
Alaska Expedition Cessna 206A · Accident: total loss of engine power (mechanical failure) during initial climb
From an unrecorded airport to Merle K (Mudhole) Smith Airport (PACV)
Event
- NTSB case
- ANC99LA114
- 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
- 0
- 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
Cessna 206A
- Aircraft type
- Cessna 206
- Category
- Airplane
- 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
- N4605F
- Operator
- Alaska Expedition
- Onboard fatalities
- Unknown
- Route
- From not recordedTo Merle K (Mudhole) Smith Airport (PACV), 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 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
- Initial climb
- 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
- Fuel system, fuel flow divider/distributor › Corroded
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The commercial certificated pilot departed from his company's fishing lodge to begin a cross-country business flight. About 300 feet above the ground, the engine suddenly quit. The pilot switched fuel tanks, activated the engine boost pump, and began a turn into the wind. The engine did not restart. The pilot selected an open area of marsh for an emergency landing area. When the airplane touched down, the nose wheel separated from the nose wheel strut, and the airplane nosed down in the soft terrain. The airplane received damage to the engine, propeller, and the left wing. A postaccident examination of the engine by a mechanic found corrosion, and blockage of the vent hole of the engine manifold valve housing. The manifold valve is comprised of a fuel inlet, a diaphragm chamber, and outlet ports for fuel lines to each cylinder. The spring loaded diaphragm operates a valve in the central bore of the lower chamber of the valve body. Fuel pressure below the diaphragm opens the valve to allow fuel to flow to each cylinder. A spring above the diaphragm retains the valve in the closed position, absent any fuel pressure. The upper chamber of the valve housing, containing the spring, is vented to the atmosphere.
Probable cause
A loss of engine power due to corrosion/blockage of the fuel flow divider vent hole. A factor was unsuitable terrain for a forced landing.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ANC99LA114
- Event ID
- 20001212X19402
- Case number
- ANC99LA114
- 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. 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: 825ff00fdfaa028436cbbd9cb770cc3323ed117966ba97ad1b05f1fac31dd9de; retrieved 2026-09-22T14:17:41.842Z.