SEA98FA105 · Cessna 340
Cessna 340 · Accident: in flight encounter with weather en route
From Bozeman Yellowstone International Airport (BZN) to Glacier Park International Airport (FCA)
Event
- NTSB case
- SEA98FA105
- 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
- 1 · 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
Cessna 340
- Aircraft type
- Cessna 340
- 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
- N88JH
- Operator
- Curtis M. Moeller · private individual
- Onboard fatalities
- Unknown
- Route
- From Bozeman Yellowstone International Airport (BZN), Bozeman, MTTo Glacier Park International Airport (FCA), Kalispell, 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
- 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 › Weather radar, improper use of
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
During preflight weather briefing, the pilot was briefed to expect rain showers and thunderstorms up to Level 6 (extreme) intensity along his route of flight. The pilot, whose aircraft was equipped with radar and Stormscope equipment, filed an instrument flight rules (IFR) flight plan and departed under IFR. Upon radar contact, ATC cleared the pilot direct to his destination. 21 minutes later, while flying on the direct (northwesterly) track to the destination, the aircraft entered a Level 4 thunderstorm cell. The pilot told air traffic control (ATC), '...[I] hit a pretty heavy cell here [I've] got lightning all around and picking up some hard ice.' The crew of another aircraft deviating to the north of the storm suggested the aircraft turn north to exit the weather. ATC relayed this suggestion, and the pilot replied he was turning to the north. The aircraft then entered a right turn; radar contact was lost after approximately 90 degrees of turn. 6 seconds after the time at the last radar position, the pilot radioed, '...[I'm] in a tremendous downdraft [I'm] losing altitude six thousand'. This was the last transmission received from the accident aircraft. A search for the aircraft was initiated; the aircraft wreckage was found approximately 11 1/2 hours later, approximately 1 1/2 miles south of the last radar position. Logbooks recovered from the wreckage indicated the pilot was not current for IFR flight.
Probable cause
The pilot's improper or inadequate use of the aircraft's weather avoidance equipment, resulting in penetration of a Level 4 thunderstorm and subsequent loss of aircraft control from which the pilot did not recover. Factors included a thunderstorm and the pilot's lack of instrument currency.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record SEA98FA105
- Event ID
- 20001211X10419
- Case number
- SEA98FA105
- 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: local date, investigation status. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 1998-06-19.
- API snapshot SHA-256: 8d8b361b3aafd470242828d1e4364ebe91a4a8d019a90b242df33ac3127240de; retrieved 2026-09-20T22:32:17.111Z.