What item must be checked during the pre-takeoff contamination check?

The item that must be checked during the pre-takeoff contamination check is the wing at the emergency exit. This specific check is crucial because it ensures that the wings, which are critical for lift and overall aircraft performance, are free from ice, snow, or any other contamination that could impair flight safety. Contamination on the wings can alter their aerodynamic properties, leading to increased drag and potentially compromising the aircraft’s ability to gain altitude or maneuver effectively.

In the context of the pre-takeoff process, an accurate assessment of the wing’s condition is essential—especially at emergency exits where immediate egress needs to be considered in the event of an emergency. Ensuring that this area is clear of contaminants contributes to a safe and efficient flight operation.