What happened
On January 11, 2017, an Embraal 170-200 was operating a scheduled flight from Warsaw (EPWA) to Zurich (LSZH). Due to loading delays in Warsaw, the flight arrived late in Zurich, creating pressure on the crew to prepare the aircraft quickly for its return leg. While the captain inspected the aircraft and supervised refueling, the first officer prepared the flight management computer and reviewed ATIS information.
After receiving clearance for flight "DEGES 3L," the crew departed from runway 32. During the climb, the aircraft encountered turbulence and icing conditions. Following takeoff, Zurich Approach (APP) instructed the crew to turn left toward point KOLUL. However, the aircraft was already established in a right turn. To initiate the required left turn via the navigation system, the pilot flying switched to heading mode and set a left heading to intercept the new course.
At 4,500 feet, as the crew accelerated to 210 knots IAS and retracted the flaps, the controller notified them that the aircraft was still performing a right turn. The controller then issued a new heading of 150 degrees, which the crew executed, effectively continuing the right-hand turn. The aircraft was subsequently transferred to area control, and the remainder of the flight proceeded without further incident.
The investigation
The investigation focused on why the aircraft failed to follow the initial left-turn instruction and why the crew did not recognize the deviation. The investigation established that the crew had programmed a different Standard Instrument Departure (SID) into the flight management computer than the one authorized by Air Traffic Control.
Findings
- The crew programmed an incorrect SID into the flight management computer, which did not match the ATC clearance.
- Although the crew verified the SID settings in the computer, they failed to detect the discrepancy between the programmed procedure and the ATC clearance.
- The crew was unaware of the reason for the vectoring to the left and the subsequent heading changes.
- The air traffic controller did not inform the crew of the specific reason for the vectoring instructions.