When should a pilot request a taxi clearance?

• A. After the aircraft has taken off
• B. Before leaving the terminal
• C. Before moving the aircraft on the ground
• D. After receiving flight instructions

Answer: (C)

A pilot should request a taxi clearance before moving the aircraft on the ground to ensure safety and compliance with air traffic control procedures. This request is essential as it allows the controller to provide critical instructions regarding the taxi route, ensuring the aircraft navigates safely to the active runway while avoiding collisions with other aircraft, vehicles, or obstacles on the airfield.

Taxi clearances help maintain an organized flow of traffic on the ground, directing aircraft to use designated taxiways and holding positions. This process is particularly important in busy airports with multiple arrivals and departures concurrently. By requesting the clearance prior to movement, pilots can confirm that the air traffic control is aware of their intentions and can manage the airspace appropriately, reducing the risk of misunderstandings or accidents.

The other options would either not necessitate a taxi clearance or occur at inappropriate times. For instance, requesting clearance after takeoff would be irrelevant, as the aircraft would already be airborne. Similarly, asking for a taxi clearance after receiving flight instructions or before leaving the terminal does not align with the proper protocol since clearance is specifically needed for movement on the ground.