Summary
On June 16, 2017, a Boeing 737-800 operated by Enter Air experienced a flap system malfunction during departure from Palermo Airport (LICJ). The crew executed the non-normal checklist and continued to Toulouse Airport (LFBO), where a safe landing was performed with flaps extended to 15 degrees. Post-flight maintenance identified and replaced a defective outboard left flap proximity sensor.
Event Details
After retracting the flaps following takeoff, the left flaps in transit indicator (LE FLAPS IN TRANSIT) remained illuminated. The flight crew performed the corresponding non-normal checklist procedure and decided to proceed to the planned destination, Toulouse Airport in France. The aircraft landed with flaps set to 15 degrees in accordance with the checklist. The captain made an entry in the technical log and notified the maintenance control center (MCC).
Investigation Findings
Ground technicians inspected the aircraft and traced the anomaly to the outboard left flap proximity sensor. The sensor was replaced, and operational tests were successfully completed. The aircraft was subsequently returned to service. The incident was recorded in the operator's SMS database and classified according to company criteria. It was also included in safety performance indicators monitored under the SMS manual.
Cause
The incident was caused by a malfunction of the left outboard flap proximity sensor.