Event Summary
The pilot reported that the airplane experienced an electrical malfunction 2-3 minutes after takeoff. After multiple unsuccessful attempts to reset the electrical system, the pilot attempted to manually lower the landing gear in preparation for a landing. He reported that he was able to actuate the manual gear extension handle; however, the landing gear would not fully extend and lock. After multiple additional attempts to fully lower the gear, the pilot initiated a landing with the main landing gear in the midrange position.
Examination Findings
Examination of the landing gear system by representatives from the NTSB and FAA revealed that the landing gear actuator housing fractured and separated from the gearbox. Damage was also noted to the actuator drive coupling. Representatives from the FAA and the manufacturer of the gear assembly conducted the teardown and examination of the electric landing gear actuator motor. During the examination, 14 volts was applied to the actuator motor in an attempt to functionally test the DC motor. The electric motor did not respond or draw current. Further examination of the motor revealed that the two brushes in the motor were of dissimilar type and design and showed signs of arcing. Additionally, the motor's armature showed signs of severe wear.
Maintenance History
Logbook records indicated that the electric landing gear motor was serviced on February 1, 2001, approximately 39 flight hours prior to the accident. The log entry indicated that the armature shaft and brushes were replaced and that the gear motor was returned to service.