What happened
During an early morning departure from Dallas Love Field, the pilot-in-imand was accompanied by a pilot-rated passenger occupying the left seat. During the initial climb, the pilot noticed the aircraft was failing to gain altitude. In an attempt to increase lift, the pilot applied 1/4 flaps while maintaining an airspeed of approximately 105 knots. However, as the airspeed deteriorated to about 90 knots, the pilot retracted the flaps.
While both engines appeared to be developing power—with 2,300 RPM and 26 inches of manifold pressure—the pilot noted that the right engine behaved as if it were operating on only one magneto. The passenger did not observe any engine irregularities until after the aircraft struck a power line, at which point the right engine began making sounds consistent with cutting out.
The investigation
Examination of the wreckage showed that both main landing gear were in the down position and the nose landing gear was located within the crushed nose of the aircraft. Investigators found the right main landing gear up-lock was fractured. The landing gear control lever was positioned halfway between the up and down positions, the flap control lever was in the full down position, and the throttle, propeller, and mixture control levers were all set to full forward. An examination of the flap actuator showed it was fully extended, with an exposed actuating rod measuring 3 inches, which the manufacturer defines as the flaps being fully extended.
Regarding the right engine, investigators found that the ignition lead cover plate for the right magneto had separated from the magneto. This specific magneto had been replaced by the pilot the previous day in Tulsa, Oklahoma. Additionally, cracks measuring 2 inches in length with black deposits were discovered on cylinders #1 and #4 near the intake ports. It appeared that these intake ports had been modified.
Performance data indicated a single-engine rate of climb of approximately 289 feet per minute at an indicated airspeed of 108 miles per hour. This deviated from the flight manual requirements for maximum continuous power, which specify landing gear and flaps up, and the inoperative engine feathered.