What emergency transponder code is specifically used for indicating a hijacking?

The specific emergency transponder code designated for indicating a hijacking is 7500. This code alerts air traffic control that the aircraft is under unlawful interference, allowing for appropriate emergency actions to be taken. When pilots set their transponder to this code, it signals the situation without needing to communicate verbally, which may not be feasible in a hijacking scenario.

This code is part of a system where different transponder codes are used for various emergencies, such as 7600 for lost communications and 7700 for general emergencies. Each code serves a distinct purpose, with 7500 uniquely associated with hijacking to ensure that authorities respond quickly and correctly to the serious and potentially life-threatening situation.