What happened
On June 15, 2015, a Cessna 152 was performing circuit training at the Depułtycze Królewskie (EPCD) aerodrome. The flight consisted of a series of landings on runway 19L, all of which were initially completed without incident. Prior to the final landing of the sequence, the pilot had utilized a 30-degree flap setting.
Following the landing, the pilot prepared for a subsequent takeoff by turning off the carburetor heat, adjusting the flaps to 10 degrees, and setting the throttle to takeoff power. During the initial climb, the pilot noticed an irregular climb performance. Upon reaching approximately 100 feet AGL, the pilot identified that the flaps were not in the intended configuration.
After reaching 350 feet AGL and increasing airspeed, the pilot executed two left-hand turns to stabilize the aircraft. Upon reaching 1500 feet AGL, the pilot reduced power and maintained a speed of 70 knots to troubleshoot the issue. The pilot verified that the flap circuit breaker was correctly engaged and reported the situation via radio. The flight concluded with a successful landing on runway 19L.
The investigation
Following the event, maintenance personnel inspected the aircraft's electrical system responsible for flap operation. The inspection focused on the flap control motor and its electrical components to determine why the flaps failed to retract as commanded.
Findings
Technical analysis revealed that the stuck commutator brushes in the electric flap control motor prevented the mechanism from functioning correctly. Maintenance crews cleaned the brushes, cleaned the commutator and rotor with technical spirit, and lubricated the rotor bushings. Following these repairs, the flap system was tested and confirmed to be fully operational, and the aircraft was returned to service.