Synopsis
A pilot experienced a loss of power during the initial climb after takeoff. A witness observed the airplane depart and stated "the engine didn't sound right," and the airplane just barely cleared the trees at the end of the runway. During a turn back toward the airport, the airplane pitched down and impacted trees.
Sequence of Events
The pilot reported the power loss shortly after takeoff while climbing. After the turn, the airplane lost altitude and struck trees.
Examination Findings
Post-accident examination of the wreckage did not disclose any pre-impact mechanical malfunctions of the airframe or engine. The airplane was equipped with a manual 3-point primer system. Spark plugs removed from the three cylinders that contained primer lines revealed a "heavy coat of black sooty material" present on the electrodes. The spark plug removed from the cylinder that did not contain a primer line was "clean." Additionally, the primer control in the cockpit was observed in a forward, but unlocked position. Review of the airplane's operating handbook revealed that part of the "Normal Procedures, Before Takeoff" checklist included the item "Primer...locked."
Pilot Background
The pilot had logged 270 hours of flight experience since August 1996, all in turbine-powered airplanes, except for a 1.8-hour checkout in the accident airplane.