SEA04FA003 · Cessna 177B
Cessna 177B · Accident: loss of engine power en route
From Great Falls International Airport (GTF) to 42S · Poplar, MT
Event
- NTSB case
- SEA04FA003
- 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
- 2 · 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
Cessna 177B
- Aircraft type
- Cessna 177
- 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
- N30921
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Great Falls International Airport (GTF), Great Falls, MTTo 42S · Poplar, 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
- Also codedOther events the NTSB coded in the sequence, such as a wire strike after a loss of power. Flight Findings uses them for its kinds of event. Glossary
- Tree(s)
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Cause areas
- Fuel system, carburetor › Separation
- Pilot in command › Compensation for wind conditions, inadequate
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
While in cruise flight the aircraft suddenly lost all engine power, and after unsuccessfully attempting to get the engine restarted, the pilot attempted a forced landing on a nearby gravel road. During that attempt, the pilot failed to adequately compensate for strong crosswinds, and therefore inadvertently clipped the top of a tree that was located immediately adjacent to the approach end of the section of road he was trying to land upon. A post-accident inspection of the engine determined that the carburetor had separated from the engine in cruise flight, due to the fact that there were no longer any nuts on any of the four carburetor mount retaining lug bolts. The carburetor mounting flange holes all remained intact, and none of the four mounting bolts showed any signs of damaged or distorted threads. Recent use of Marihuana was determined to have impaired the pilot's judgment at the time he was attempting the forced landing.
Probable cause
The total loss of engine power in cruise flight due to the separation of the carburetor from its mounting bolts, and the pilot's failure to adequately compensate for strong crosswinds while attempting the subsequent forced landing. Additional factors include strong crosswinds, a tree immediately adjacent to the gravel road that the pilot chose to land on, and the pilot's impairment due to recent use of Marihuana.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record SEA04FA003
- Event ID
- 20031017X01769
- Case number
- SEA04FA003
- 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: a700240d470419a1b9dcf2f24f768a7feed2f2b7dfeb99695700199f14b62778; retrieved 2026-09-20T18:54:34.675Z.