Alpine Air Beech B-99 accident
Beech B-99 · Accident: airframe, component or system failure en route
From Billings Logan International Airport (BIL) to Glacier Park International Airport (GPI)
Event
- NTSB case
- SEA07LA133
- 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
- Charter & commuter
- 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
Beech B-99
- Aircraft type
- Beechcraft B-99
- 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
- N950AA
- Operator
- Alpine Air
- Onboard fatalities
- Unknown
- Route
- From Billings Logan International Airport (BIL), Billings, MTTo Glacier Park International Airport (GPI), 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 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
- 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
- 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
- Hydraulic system, actuator › Failure, total
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 about 40 nautical miles into the flight, he heard a "clunk" and the red unsafe light in the gear handle came on. He verified that all systems were functioning normally, and he cycled the landing gear up and down to see if that would solve the problem. The unsafe light remained illuminated. The pilot returned to the departure airport and circled for several hours to burn his fuel load down. He said that at one point he flew low over the runway so the company mechanic, with the aid of a light from an airport vehicle, could visually check the nose gear position. It was hanging out of the wheel well at approximately a 45-degree angle. Upon landing, the airplane settled to its nose during landing rollout. Examination of the airplane revealed that the nose gear actuator mount bracket area was bent and wrinkled. The nose gear actuator shaft had fractured just above the clevis bolt, which attaches to the drag brace. The failed actuator had been installed on July 26, 2006. The Beech B-99 maintenance manual states that the hydraulic actuator needs to be overhauled or replaced every 10,000 hours; maintenance records indicate that this one had 231.4 hours on it at the time of the accident. Metallurgist examined the failed actuator and concluded that all of the fractures were overstress, and no preexisting fatigue signatures were evident. The airframe had accumulated 34,613.2 hours of flying time, at the time of the accident.
Probable cause
The total failure of the nose landing gear actuator and the subsequent nose gear collapse during landing.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record SEA07LA133
- Event ID
- 20070703X00870
- Case number
- SEA07LA133
- 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, 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: f5b2cdcb6749040d7ea25a4c45c989eacb358b6a6328a4f15abc883ad04b6962; retrieved 2026-09-18T14:44:24.043Z.
- The NTSB's operator name is blank for N950AA; the operator shown is the name the NTSB records it doing business as.