What check is performed by the flight crew before departure to assess frozen contamination?

The pre-flight check is a critical part of flight operation that involves various inspections, one of which includes assessing the aircraft for any frozen contamination. During this check, the flight crew thoroughly examines the aircraft’s critical surfaces—such as wings, tail, and control surfaces—to ensure that they are free of ice, snow, or frost that could adversely affect the aircraft's performance and safety.

This inspection is essential because any frozen contamination could alter the aerodynamics of the aircraft, especially during takeoff and landing phases. If such contamination exists, the crew must ensure that proper de-icing or anti-icing procedures are employed before the aircraft takes off, safeguarding against potential mishaps during flight.

In contrast, the post-departure check is typically related to procedures and assessments once the aircraft is already airborne, the final inspection is generally more focused on final walk-around confirmations just before taxiing, and the pre-takeoff procedure involves specific checks related to the aircraft’s readiness for takeoff rather than contamination assessments. Therefore, the pre-flight check is the most appropriate context for assessing any frozen contamination on the aircraft.