What does an emergency squawk of 7600 indicate?

An emergency squawk of 7600 indicates a loss of communication. When pilots encounter a situation where they can no longer communicate with air traffic control—due to radio failure, for instance—they are trained to set their transponder to squawk 7600. This alerts air traffic controllers and other aircraft that the flight is experiencing communication difficulties, enabling them to take appropriate actions to assist.

Setting the transponder to 7600 is a standardized procedure recognized internationally, making it an effective way for pilots to convey their communication loss while continuing with their flight. It signals to controllers that they should attempt to make visual contact or provide any necessary assistance, while also looking for other indications of the aircraft's situation through its flight path or previous communications.