What is the phraseology to authorize an aircraft to take off?

• A. Aircraft Runway Clearance
• B. Runway Clearance Granted
• C. (ACID) RUNWAY 28R, CLEARED FOR TAKEOFF
• D. Takeoff Approved

Answer: (C)

The phraseology to authorize an aircraft to take off is specific and standardized to ensure clarity and safety in communication between controllers and pilots. The correct choice states, "(ACID) RUNWAY 28R, CLEARED FOR TAKEOFF," where ACID stands for the aircraft's call sign. This phraseology clearly conveys that the aircraft is authorized to take off from the designated runway, which in this case is 28R.

Using the term "CLEARED FOR TAKEOFF" is critical as it indicates that the aircraft has been given permission to proceed with the takeoff, while specifying the runway ensures that there is no confusion about the location. Air traffic control uses these standardized phrases to maintain safety and efficiency in operations, and this particular phrase is recognized and understood universally among pilots and controllers.

Other options do not meet the precision required for takeoff authorization. For instance, simply using "Aircraft Runway Clearance" or "Runway Clearance Granted" lacks the essential detail of the specific runway and does not include the required phrase "CLEARED FOR TAKEOFF." Similarly, "Takeoff Approved" does not follow the established phraseology and could lead to ambiguity in communication.