SEA92LA110 · Piper PA-28-140
Piper PA-28-140 · Accident: in flight encounter with weather en route
From Priest River Municipal Airport (1S6) to Lewistown Municipal Airport (LWT)
Event
- NTSB case
- SEA92LA110
- 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
- Instrument Meteorological Cond
Piper PA-28-140
- Aircraft type
- Piper PA-28
- 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
- N6434R
- Operator
- Chamberlain, Dwight N. · private individual
- Onboard fatalities
- Unknown
- Route
- From Priest River Municipal Airport (1S6), Priest River, IDTo Lewistown Municipal Airport (LWT), Lewistown, 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
- In flight encounter with weather
- 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
- Pilot in command › Clearance, not maintained
- Pilot in command › Weather forecast, disregarded
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
AFTER RECEIVING A WEATHER BRIEFING DURING WHICH VFR FLIGHT WAS NOT RECOMMENDED, THE NON-INSTRUMENT RATED PILOT DEPARTED PRIEST RIVER, EN ROUTE TO LEWISTOWN. APPROXIMATELY 50 NAUTICAL MILES SHORT OF HIS DESTINATION, OVER HILLY/MOUNTAINOUS TERRAIN, THE AIRCRAFT COLLIDED WITH TREES NEAR THE TOP OF A 7650 FOOT RIDGELINE AND CRASHED. THE PILOT REPORTED LOW CEILINGS AND 1.5 MILES VISIBILITY RESTRICTED BY MODERATE RAIN AND CLOUDS AT THE TIME OF THE ACCIDENT. HE ALSO REPORTED A LOSS OF ALTITUDE AT FULL POWER APPROACHING THE RIDGELINE THAT WAS NOT ATTRIBUTED TO ANY AIRCRAFT MALFUNCTION.
Probable cause
THE PILOT IN COMMAND'S DISREGARD OF THE WEATHER FORECAST AND FAILURE TO MAINTAIN CLEARANCE WITH TREES/TERRAIN. FACTORS CONTRIBUTING TO THE ACCIDENT WERE: HILLY/MOUNTAINOUS TERRAIN, WEATHER CONDITIONS: RAIN, LOW CEILINGS AND DOWNDRAFTS, TREES AND THE PILOT IN COMMAND'S CONTINUED FLIGHT INTO KNOWN ADVERSE WEATHER.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record SEA92LA110
- Event ID
- 20001211X14740
- Case number
- SEA92LA110
- 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: 2198310595275b7e42ab415c1d7738dc2c26cdbd05c0d4ae42f641b94adf5df0; retrieved 2026-09-21T23:16:29.230Z.