What emergency transponder code is used for a hijacking?

The emergency transponder code used for a hijacking is 7500. This code is specifically designated for scenarios where an aircraft is under unlawful interference, such as a hijacking situation. When a pilot activates this code, it alerts air traffic control and other pilots that the aircraft may need assistance due to a potential threat or emergency.

In contrast, the other codes serve different purposes: 7600 indicates a radio communication failure, which means the aircraft is experiencing issues with its communication equipment; 7700 represents a general emergency, which could refer to any situation that requires immediate assistance that does not fall under more specific codes; and 7200 is used for VFR (Visual Flight Rules) flights that may not be in communication with air traffic control for operational reasons, such as flying outside controlled airspace but still requiring traffic advisories.

Understanding the purpose of these transponder codes is crucial for pilots, as it ensures clear communication with air traffic control and helps coordinate responses to various emergencies effectively.