What does a transponder code of 7600 indicate?

A transponder code of 7600 specifically indicates a loss of communication. When a pilot sets the transponder to this code, it alerts air traffic control that they are not able to communicate with the aircraft, typically due to a radio failure. This code prompts air traffic controllers to take specific actions, such as providing additional visual separation and attempting communication through alternative means.

In contrast, codes such as 7500 signal a hijacking situation, while codes like 7700 are used for general emergency situations. A navigation failure does not have a specific transponder code associated with it and usually must be reported through other means. Thus, knowing that 7600 signifies lost communication is crucial for understanding the protocols and responses necessary in such scenarios.