LAX94LA114 · Cessna 150F
Plus One Flyers Cessna 150F · Accident: partial loss of engine power (mechanical failure) during initial climb
From an unrecorded airport to Montgomery-Gibbs Executive Airport (MYF)
Event
- NTSB case
- LAX94LA114
- 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
- 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
Cessna 150F
- Aircraft type
- Cessna 150
- 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
- N8855S
- Operator
- Plus One Flyers
- Onboard fatalities
- Unknown
- Route
- From not recordedTo Montgomery-Gibbs Executive Airport (MYF), San Diego, 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
- Initial climb
- 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
- Partial loss of engine power (mechanical failure)
- Also codedOther events the NTSB coded in the sequence, such as a wire strike after a loss of power. Flight Findings uses them for its kinds of event. Glossary
- Stall/mush
- 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
- Pilot in command › Airspeed(vs), not maintained
- Pilot in command › Operation with known deficiencies in equipment, initiated
- Pilot in command › Stall/mush, inadvertent
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
While in cruise, the pilot noticed that his engine began running roughly. He made a precautionary landing at a nearby airport, but was unable to identify the problem. A second ground run-up developed only 2,100 rpm's at full throttle. He then called the operator. After a discussion, he decided that if the engine performance improved, he would fly back. On the next run-up, the rpm improved in the 2,200-to-2,300 rpm range, and the pilot felt this was fine for takeoff. The takeoff roll seemed slower than normal, so he decided to climb over the airport in case of an emergency. On climbout at 100-to-200 feet agl, the engine again began running roughly. He began a shallow turn back toward the runway, and lost control of the aircraft. The aircraft stalled, impacted the ground, and nosed over. An inspection of the engine showed the rocker arm boss on the No. 1 cylinder had fractured due to fatigue cracking. Lab analysis showed the boss was welded during cylinder overhaul, a procedure not allowed by Continental.
Probable cause
1) the pilot's decision to takeoff in an aircraft with a known, yet unresolved, engine performance deficiency, and 2) the pilot's failure to maintain an adequate airspeed while maneuvering back to the runway. A factor in the accident was the weld repair of the cylinder head rocker arm boss during overhaul, which led to a fatigue failure of the component.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record LAX94LA114
- Event ID
- 20001206X00761
- Case number
- LAX94LA114
- 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: e1e54f37d6275047c794cb322c7e1544b2f99d0c477abfb6ac5560e960b10d5d; retrieved 2026-09-21T14:04:52.596Z.