WPR12LA396 · Beech G35
Beech G35 · Accident: clear air turbulence encounter en route
From Mefford Field (TLR) to Oceano County Airport (L52)
Event
- NTSB case
- WPR12LA396
- 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
- 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
Beech G35
- Aircraft type
- Beechcraft 35
- 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
- N4454D
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Mefford Field (TLR), Tulare, CATo Oceano County Airport (L52), Oceano, CA
- 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 · descent
- 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
- Clear air turbulence encounter
- 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
- Environmental issues › Conditions/weather/phenomena
- Personnel issues › Action/decision
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot reported that, while the airplane was descending to land at an indicated airspeed of about 180 mph, it encountered turbulence for about 2 seconds. The pilot immediately reduced power and slowed the airplane to about 140 mph. The pilot continued the approach and landed the airplane without further incident. After landing, the pilot observed deformities along the fuselage.
A postaccident examination of the airplane revealed structural twisting damage to the aft fuselage, consistent with an overload failure in a tail downward direction. According to the airplane manufacturer, the damage was also consistent with damage seen on other airplanes of the same make and model that had encountered turbulence while descending at speeds higher than the airplane's design maneuvering speed. A review of the Pilot's Operating Handbook showed that the airplane's reported airspeed of 180 mph at the time it encountered the turbulence was within the caution operating range of 176 to 202 mph and was higher than the design maneuvering speed. It is likely that the pilot's exceedance of the design maneuvering speed while the airplane was descending in turbulence resulted in the structural damage to the aft fuselage.
Probable cause
The pilot’s exceedance of the design maneuvering speed during descent in turbulence, which resulted in structural damage to the aft fuselage.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR12LA396
- Event ID
- 20120905X22842
- Case number
- WPR12LA396
- 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: 340e335c1860d2f1e34dc994d5e3a200fb1ccbd94914c9b163c93ab2bade5c8d; retrieved 2026-09-15T19:42:04.986Z.