SEA96LA203 · Forney F-1
Forney F-1 · Accident: loss of engine power en route
From Townsend Airport (8U8) to Bozeman Yellowstone International Airport (BZN)
Event
- NTSB case
- SEA96LA203
- 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
Forney F-1
- Aircraft type
- Forney F-1
- 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
- N7551C
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Townsend Airport (8U8), Townsend, MTTo Bozeman Yellowstone International Airport (BZN), MT
- 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 · cruise
- 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
- Pilot in command › Maintenance, service of aircraft/equipment, inadequate
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot shut down the engine and made a forced landing on a dirt road after losing oil pressure in cruise flight. The airplane sustained substantial damage when it contacted sage brush, which forced it off the right side of the road and down an embankment. According to the pilot, the dip stick indicated the airplane had 2.3 quarts of oil remaining after the forced landing. The pilot noted that after the airplane was recovered, the dip stick indicated 1.5 quarts. He had departed on the flight with the dip stick indicating 2.4 quarts of oil in a system that he believed to have 4.25 quarts capacity. Type Certificate Data Sheet information stated that the oil capacity was 5 quarts on this installation. Two quarts was considered to be minimum operating oil supply.
Probable cause
the pilot's failure to adequately service the engine with oil before flight, which resulted in a loss of oil pressure and a subsequent forced landing. The high vegetation and embankment at the forced landing site were related factors.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record SEA96LA203
- Event ID
- 20001208X06638
- Case number
- SEA96LA203
- 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: 808d6b174ec6e58df35fe3f44e2f450fae6d7483357bbdcf195898cd914f9d2f; retrieved 2026-09-22T21:20:49.583Z.