West Air Cessna 208B accident
Cessna 208B · Accident: loss of control on ground while taxiing
From Ontario International Airport (ONT) to Meadows Field (BFL)
Event
- NTSB case
- WPR11FA158
- 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
Cessna 208B
- Aircraft type
- Cessna 208
- 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
- N930FE
- Operator
- West Air
- Onboard fatalities
- Unknown
- Route
- From Ontario International Airport (ONT), Ontario, CATo Meadows Field (BFL), Bakersfield, CA
- Aircraft age
- About 24 years (built 1987)
- 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
- Taxi · from runway
- Defining eventThe 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
- Loss of control on ground
- 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
- Aircraft › Aircraft oper/perf/capability
- Aircraft › Aircraft systems
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot of the cargo flight reported that, after landing at the destination airport, he taxied about 1.9 miles using the customary route toward the assigned cargo unloading area. The airplane turned right and then left without experiencing any anomalies. The pilot then applied full right rudder and brake pressure to negotiate the last 90-degree turn; however, the airplane did not turn as expected and subsequently impacted two trucks and a van. A witness reported that the airplane's taxi speed appeared normal throughout its approach and final turn.
The examination of the accident master brake cylinders and the cylinders from two other airplanes that had reportedly failed revealed several anomalies that could have caused or contributed to the airplane's failure to turn as expected. The examination revealed that the right pedal assembly may interfere with the adjacent floorboard when the brake pedal is compressed to or near the full-internal cylinder travel stop, which may cause an additional stop and limit the overall travel of the cylinder. The examination also revealed that numerous components or items may prevent the master brake cylinders from fully extending after the brakes are released and adequate travel (reduced pressure) when the brakes are subsequently actuated. Additionally, the examination revealed that the brake fluid may bypass the piston O-ring or Stat-O-Seal if parts are damaged or excessively worn. The cylinder manufacturer, in conjunction with the FAA, published Service Bulletin CAB-32-01, Revision 1, to address the noted mechanical anomalies.
Probable cause
The malfunction of a master brake cylinder, which resulted in a loss of braking action and subsequent loss of directional control and collision with three vehicles during taxi. Contributing to the accident was the inappropriate design and manufacture of the master brake cylinders.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR11FA158
- Event ID
- 20110310X55313
- Case number
- WPR11FA158
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
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: a256405f10be72307a97a33e79434111eb7840c23c6aa087b0241199d3b2e871; retrieved 2026-09-15T15:53:50.556Z.