LAX00LA312 · Cable-Breigler BG-12BD
Cable-Breigler BG-12BD · Accident: airframe, component or system failure on approach
From Mountain Valley Airport (L94) to an unrecorded destination
Event
- NTSB case
- LAX00LA312
- 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
- Visual Meteorological Cond
Cable-Breigler BG-12BD
- Aircraft type
- Cable Breigler BG-12
- Category
- Glider
- 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
- N4458
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Mountain Valley Airport (L94), Tehachapi, CATo not recorded
- 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
- Approach
- 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
- Destroyed
Cause areas
- Flight control, flap attachment › Overload
- Flight control, flap attachment › Separation
- Pilot in command › Airspeed, excessive
- Wing › Overload
- Wing › Separation
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The glider was returning to the airport when the left wing and flap separated; the glider entered an uncontrolled descent into terrain. It was about 1 mile north of the airport and about 2,000 feet above the ground. It appeared to be preparing to enter downwind for the landing pattern for runway 27. The altitude was higher than normal for this approach, and the glider's speed was very fast. This glider did not have speed brakes; the flaps were used to slow it down. The flaps appeared to be activated when the left flap and wing separated. A section of the rear spar fractured and separated from the wing. The left wing spar fracture surface exhibited twisting characteristics.
Probable cause
The pilot exceeded the airspeed limit for operation of the flaps resulting in flap and wing overload and separation.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record LAX00LA312
- Event ID
- 20001212X21782
- Case number
- LAX00LA312
- 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: 8c0f1d449c22c737c5dded3a90a73b273a93d5f820794fb60f0226fe4b0d3245; retrieved 2026-09-20T20:54:34.300Z.