What transponder code is designated for military use only?

The transponder code designated for military use only is 7777. This specific code is reserved for military aircraft operations and is used to identify military flights in controlled airspace. The use of a dedicated transponder code helps air traffic control distinguish military aircraft from civilian traffic, enabling better situational awareness and management of airspace.

In the context of air traffic management, different codes are allocated for various purposes, including search and rescue, emergencies, and military operations. While other codes exist for different functions or general air traffic, 7777 explicitly stands out as the code for military utilization, ensuring that military aircraft receive the necessary attention and clearance in busy airspace. This dedicated classification supports operational security and efficiency for military engagements.