What happened
On November 18, 2015, an Embraert 175 operated by PLL LOT was taxiing for takeoff at Warsaw Chopin Airport (WAW) when a TAT1 FAIL alert appeared on the Engine Indication and Crew Alerting System (EICAS). In response to the alert, the flight crew halted the taxiing process to attempt a system reset.
Following the unsuccessful attempt to clear the indication through a reset, maintenance personnel were summoned to the aircraft. Technicians applied ADD 490 in accordance with the Minimum Equipment List (MEL) 34-15-03/B, which allowed the aircraft to proceed with its flight operations.
The investigation
The PKBWL investigation focused on the origin of the EICAS alert and the effectiveness of the crew's response. The investigation established that the technical malfunction was localized to the temperature sensing equipment and that the aircraft was properly managed under the applicable MEL provisions.
Findings
- The primary cause of the incident was a malfunctioning Total Air Temperature Sensor.
- The fault did not recur following the replacement of the faulty component.