Timberline Beech B100 accident
Beech B100 · Accident: on ground/water collision with terrain/water during landing
From Billings Logan International Airport (BIL) to Miles City Airport - Frank Wiley Field (MLS)
Event
- NTSB case
- SEA96LA038
- 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
- Charter & commuter
- 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
Beech B100
- Aircraft type
- Beechcraft 100
- 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
- N924WS
- Operator
- Timberline
- Onboard fatalities
- Unknown
- Route
- From Billings Logan International Airport (BIL), Billings, MTTo Miles City Airport - Frank Wiley Field (MLS)
- 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 135: Air Taxi & Commuter
- 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
- Landing · landing roll
- 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
- On ground/water collision with terrain/water
- 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
- Airport personnel › Airport snow removal, inadequate
- Airport personnel › Notams, not issued
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilots obtained a complete weather briefing for their IFR flight. Before landing at their destination, they attempted to obtain an airport advisory on Unicom, but received no response. They landed on the runway in low visibility with the runway lights visible. After touchdown, the left main landing gear contacted a berm or snowbank on the left side of the plowed area, and the pilots were unable to maintain directional control. The aircraft drifted off the left side of the runway and came to rest on a reverse heading. The runway, which was 100 feet in width, had been plowed to about 45.5 feet width along the centerline. No notams had been filed concerning the partially plowed condition of the runway. The second officer (commercial pilot) noted that during the weather briefing, the pilot-in-comand had been advised of thin, loose snow on the runway.
Probable cause
Failure of airport personnel to properly remove snow from the runway or issue an appropriate notam concerning the runway condition. Factors relating to the accident were: the low light condition at dawn, and the snowbank or berm that was left on the runway.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record SEA96LA038
- Event ID
- 20001208X05200
- Case number
- SEA96LA038
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (5)
- 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: 3934764bc0e4acb9e91fec379cfc2189ce7ea0ba6b35f0aab803a07606f5aa76; retrieved 2026-09-18T17:54:54.018Z.
- The NTSB's operator name is blank for N924WS; the operator shown is the name the NTSB records it doing business as.