CEN12LA008 · Johnston William Alfred JR KOLB MARK III
Johnston William Alfred JR KOLB MARK III · Accident: loss of engine power (partial) during initial climb
From Versailles, MO to Versailles, MO
Event
- NTSB case
- CEN12LA008
- 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
Johnston William Alfred JR KOLB MARK III
- Aircraft type
- Johnston William Alfred JR KOLB MARK
- 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
- N9144E
- Operator
- Everett Gregory A
- Onboard fatalities
- Unknown
- Route
- From Versailles, MOTo Versailles, MO
- 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
- 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 engine power (partial)
- 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
- Personnel issues › Task performance
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot stated that the accident occurred on his sixth flight in the airplane. The engine run-up for the accident flight was normal, and just after takeoff, the engine over-temperature warning light illuminated. He banked the airplane to return to the airstrip. He said he decreased the engine power to keep the temperatures down but then had to increase engine power and pitch in order to clear trees along the flight path. The engine subsequently stopped producing power. The landing gear was ripped off during the forced landing in a field and the pilot was dragged across the terrain while still in the sling-type seat, which resulted in the pilot sustaining serious back injuries.
After purchasing the airplane, the pilot installed a new engine, a ballistic recovery chute, a new fuel tank, and new fuel lines. However, he stated that he had continuing problems with high engine temperatures and a high static engine rpm. In response to these problems, the pilot replaced the static jets in both carburetors, tuned and synchronized both carburetors, and replaced the heat probes. He also installed an engine information system.
A postaccident examination of the engine and airplane revealed that both carburetors were not adjusted properly, thus restricting fuel flow; improper fuel jets were installed, which produced a richer fuel/air mixture; and the coolant water temperature probe was in the wrong location, which would have prevented accurate temperature sensing. In addition, the positions of the air deflectors, the ballistic recovery chute, and the oil injection reservoir may have affected the amount of cooling air to the engine. No evidence of internal damage was noted to the pistons and cylinders. The engine demonstrated the ability to run normally during postaccident testing. Although the exact cause of the loss of engine power was not determined, it is likely that a combination of the modifications that were made to the airplane and engine that resulted in the loss of engine power.
Probable cause
A loss of engine power due to adjustments and modifications that the pilot made to the engine and airplane.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CEN12LA008
- Event ID
- 20111006X12722
- Case number
- CEN12LA008
- 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: f1f16e8f65192683ba84963f3a9d1f8cee2f3907912ddd1734b978e519d022ba; retrieved 2026-09-15T16:48:49.183Z.