Overview
On a dark early morning departure from Dallas Love Field, a pilot-rated passenger occupied the left seat while the pilot-in-command (PIC) managed the flight. During climb out, the PIC realized the aircraft was not gaining altitude and applied 1/4 flaps in an attempt to climb. The airspeed at that time was about 105 knots. After retracting the flaps due to airspeed deterioration to about 90 knots, the aircraft still failed to gain altitude.
Sequence of Events
Both engines appeared to be developing power, with RPM at 2,300 and manifold pressure at 26 inches with fuel flow. However, the PIC thought the right engine acted as if it were operating on only one magneto. The pilot-rated passenger did not notice any engine problems until after the airplane struck the first power line, at which point the right engine began making sounds like it was 'cutting out.'
Aircraft Examination
Examination of the aircraft wreckage revealed that both main landing gear were down, and the nose landing gear was within the aircraft's crushed nose. The right main landing gear up lock was fractured. The landing gear control lever was found halfway between the up and down position. The flap control lever was in the full down position, and the throttle, propeller, and mixture control levers were full forward. Examination of the flap actuator revealed it was fully extended with the exposed actuating rod measured at 3 inches. According to the aircraft manufacturer, this would equate to the flaps being fully extended.
Examination of the right engine revealed that the right magneto's ignition lead cover plate was separated from the magneto. The magneto on the right engine had been changed by the pilot the day prior at Tulsa, Oklahoma. Cracks were found in cylinders #1 and #4 of the right engine in the vicinity of their intake ports. The cracks were 2 inches in length with black deposits. It appeared that the intake ports had been modified.
Performance Data
Performance data indicates the airplane's single-engine rate of climb was approximately 289 feet per minute with an indicated airspeed of 108 miles per hour. To attain this rate of climb, the aircraft's flight manual states that one must 'use maximum continuous power on operating engine (full throttle, 2,575 RPM) leaned to best power fuel flow, cowl flaps as required to control engine temperature within limits, landing gear up, flaps up. Inoperative engine feathered, cowl flaps closed. Climb at best rate of climb speed.'