In the context of takeoff clearance, what should the phrase following "Cancel takeoff clearance" contain?

When a takeoff clearance is canceled, it is essential that the phrase includes the reason for the cancellation. This information is crucial for pilots to understand the specific circumstances that led to the cancellation, which can help them assess their situation and decide on the next steps. Providing a reason not only enhances communication clarity but also maintains situational awareness for both the pilot and air traffic control.

In this scenario, while other aspects such as runway numbers or wind direction are important in various contexts, they do not directly pertain to the necessity of understanding why a takeoff clearance has been canceled. The focus should always be on ensuring that all parties are aware of the underlying reason to prevent confusion and ensure safety in operations.