Describe the correct sequence for a pre takeoff contamination check.

• A. All critical surfaces are checked before main cabin door is closed; wings checked no later than 5 minutes before takeoff; flight control check completed
• B. Wings only are checked
• C. Flight controls are checked after takeoff
• D. No contamination check is required

Answer: (A)

The sequence centers on verifying cleanliness and control integrity of surfaces that affect aerodynamics right before takeoff, in a way that catches any contamination early and confirms controls are functioning after deicing if needed.

First, inspect all critical surfaces while the main cabin door is still open. This accessibility allows you to visually and physically check wing leading edges, control surfaces, fuselage, and other surfaces for frost, ice, snow, or slush. Catching contamination at this stage ensures you can address it before sealing the cabin and proceeding with the rest of the checks.

Next, verify the wings and other surfaces no later than five minutes before takeoff. This timing window ensures any last-minute contamination is detected and that deicing or remediation can be completed while still providing a safe interval before departure.

Finally, perform the flight controls check. This confirms that the control surfaces move freely and respond correctly after any contamination removal or deicing, ensuring there is no binding or interference that could affect control authority during takeoff.

This order—first a comprehensive surface check with access, then a timely final surface check, then a controls check—provides the proper safeguards to detect and address contamination and confirm control functionality before flight.