Pitch Trim Switch Failure During Takeoff Roll at EPWA

Incident Overview and Aircraft Details On 7 February 2016, an incident occurred involving an Embraer ERJ-175 operated by PLL LOT SA at Port lotniczy EPWA. The aircraft was piloted by a professional line pilot. The event was classified as an incident, and no fatalities, serious injuries, or minor injuries were reported. ## Sequence of Events During the initial phase of the takeoff roll, after the thrust lever was moved but below the auto-throttle engagement level, a PITCH TRIM SWITCH1 FAIL indication appeared. The flight crew aborted the takeoff and returned the aircraft to the parking stand. An ASR report was filed, and the aircraft was handed over to technical services. ## Maintenance and Return to Service Technical services checked the systems and replaced the Horizontal Stabilizer Actuator Control Electronics (HS ACE) assembly in accordance with AMM 2743-01-000-801-A. An operational test of the system was conducted with a positive result, and the aircraft was returned to service. ## Investigation and Probable Cause The investigation was supervised by Tomasz Makowski and concluded on 3 March 2016. The most probable cause of the incident was identified as damage to the Horizontal Stabilizer Actuator Control Electronics (HS ACE) assembly of undetermined origin. The operator registered the event in its SMS database and classified it according to PLL LOT SA criteria. No safety recommendations were issued.