SEA03LA187 · Cessna 172RG
Cessna 172RG · Accident: airframe, component or system failure en route
From Felts Field (SFF) to Boundary County Airport (65S)
Event
- NTSB case
- SEA03LA187
- 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
Cessna 172RG
- Aircraft type
- Cessna 172
- 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
- N6368R
- Operator
- Pierce, David A. · private individual
- Onboard fatalities
- Unknown
- Route
- From Felts Field (SFF), Spokane, WATo Boundary County Airport (65S), Bonners Ferry, ID
- 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 · climb to 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
- Airframe, component or system 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
- Fluid, oil › Dumped
- Other maintenance personnel › Maintenance, installation, inadequate
- Other maintenance personnel › Maintenance, installation, not performed
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The pilot reported that while climbing there was a loud bang and simultaneously a spray of oil across the front windscreen. Several seconds later smoke began to develop within the cockpit and the pilot secured the engine and executed an off airport landing. The aircraft encountered rough, deeply furrowed terrain on rollout during which the landing gear collapsed. Post crash examination of the aircraft's engine revealed that the three-quarter inch hex head plug at the front of the engine, which retains the propeller governor idler gear shaft, had backed out of its threaded insert. The plug, which was found in the bottom of the engine had no safety wire attached and no safety wire was observed on the tie down point on the engine. The propeller governor idler gear shaft setscrew was loose and the gear shaft itself was missing. With the hex head plug and propeller governor idler gear shaft released, engine oil, under pressure could exit the engine. The engine had been overhauled 248.2 hours prior to the accident and then subsequently repaired for a propeller strike. It could not be determined whether any action related to the safety wiring of the hex plug or any adjustment to the set screw had been conducted at the overhaul or prop strike repair.
Probable cause
The loss of engine oil as a result of the inadequate installation of the idler gear shaft set screw and the lack of a safety wire on the hex head (oil) plug. A contributing factor was the rough and uneven terrain.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record SEA03LA187
- Event ID
- 20030922X01568
- Case number
- SEA03LA187
- 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: 912c6ddc483af038a1ea85c9e7d2d6df5d8874234a1881ce422adbe33c747c3f; retrieved 2026-09-22T08:35:51.111Z.