Accident Overview
On October 5, 2011, at 1730 central daylight time, an amateur-built Johnston Kolb Mark III, registration N9144E, collided with terrain during an off-airport forced landing following a loss of engine power on takeoff from a private airstrip in Versailles, Missouri. The student pilot, who was also the registered owner and operator, was seriously injured. The aircraft sustained substantial damage. The personal flight was conducted under 14 Code of Federal Regulations Part 91 in visual meteorological conditions; no flight plan was filed.
Pilot Account
The pilot reported that the accident occurred on his sixth flight in the airplane. Following a normal engine run-up, he decided to fly the traffic pattern at the private airstrip. Shortly after takeoff, while over a wooded area, the over temperature warning light illuminated. He banked to return to the airstrip and reduced power to approximately 1,190 rpm to manage engine temperatures. However, he later increased engine power and pitch attitude to clear trees along his flightpath. While over a bean field, the engine stopped producing power. During the subsequent landing in the field, the landing gear was torn off, and the pilot, restrained in a sling-type seat, was dragged across the terrain, resulting in serious back injuries.
Aircraft History and Modifications
The pilot purchased the already-built airplane in May 2010. After acquisition, he installed a new engine, a ballistic recovery parachute, a new fuel tank, and new fuel lines. He reported that the aircraft was taken to the Kolb factory for inspection.
Pilot reports indicated issues with the number 2 cylinder exhaust gas temperature (EGT) running high, as well as elevated number 1 cylinder head temperatures and static run rpm. The maximum allowable rpm was 6,200, but he was achieving 6,280 rpm. Advised by the repair station where he purchased the engine that the static jets might be the cause, he replaced both static jets.
He also installed an engine information system (EIS). On the first flight after the EIS installation, the number 2 cylinder EGT again indicated high. Following advice from the repair station, he tuned and synchronized the carburetors. After subsequent flights with similar issues, he replaced the heat probes and the EIS.
Due to the extent of his injuries, the pilot was unable to complete the NTSB Pilot/Operator Aircraft Accident/Incident Report.
Postaccident Examination
A postaccident examination of the engine revealed several discrepancies:
- Both the magneto-side and power takeoff-side carburetor piston slides were not adjusted properly and protruded past the carburetor body, causing the jet needles to be too low and restricting fuel flow, resulting in higher EGT.
- The main jets in both carburetors were number 170, which would produce a richer mixture compared to the standard 165 jets.
- The fuel filter was positioned between the fuel pump and fuel tank, rather than between the fuel pump and carburetors as specified in the Rotax installation manual.
- Small air deflectors were attached to the radiators to direct airflow for cooling; the left radiator was partially blocked by the oil injection tank, and the ballistic recovery chute was mounted directly in front of the engine. It is unknown how these items affected engine airflow.
- The coolant water temperature probe was mounted in the outlet socket after the thermostat, not in the center of the cylinder head as recommended, preventing proper temperature sensing.
- The injection oil tank was approximately half full.
- Pistons and cylinders showed no evidence of damage or lack of lubrication.
- With propeller blades removed due to damage, the propeller hub was reinstalled for an engine test run. With both magneto switches on, the engine started and ran for a few seconds after raw fuel was sprayed into both carburetor intakes; a second start ran for approximately 10 seconds before fuel was exhausted.
No probable cause was determined.