SEA98LA120 · Beech D35
Beech D35 · Accident: loss of engine power en route
From Pocatello Regional Airport (PIH) to an unrecorded destination
Event
- NTSB case
- SEA98LA120
- 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
Beech D35
- Aircraft type
- Beechcraft 35
- 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
- N3469B
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Pocatello Regional Airport (PIH), Pocatello, IDTo not recorded
- 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 · 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
- Loss of engine power
- 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 control › Pressure excessive
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot reported that while preparing for landing, he turned on to the base leg and reset the mixture, propeller and throttle controls to full forward. At this time the engine experienced a complete loss of power. The pilot attempted to restart the engine with no success. Due to the low altitude, the pilot felt that he could not make it to the runway and opted to land on a dirt road. During the landing roll, the left wing collided with a fence post. Post-crash inspection of the engine found that the spark plugs for two of the cylinders were 'fouled,' and that the piston heads for these cylinders were black and displayed excessive carbon build-up. The fuel metering unit was bench tested. During the test, it was found that at the high RPM setting, both the fuel pump pressure and the fuel flow pressure were excessively out of limits. It was also noted that contamination that appeared to be 'rubber' or a 'gasket-like' material was found on the fuel control valve, and the manifold valve screens. This substance was also found under and around the seat area on the fuel pump. Large amounts of 'particles' were also found inside the pump return fitting.
Probable cause
Excessive pressure in the fuel control unit. A foreign material/substance found on the fuel system screens was a factor.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record SEA98LA120
- Event ID
- 20001211X10703
- Case number
- SEA98LA120
- 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: e3af0997c30f259c7f1384a00f1eebbfcf39bbbe7394ab5b51b0d1ca0d368d56; retrieved 2026-09-22T17:34:38.835Z.