If a pilot declares an emergency and is not radar identified, which code should be assigned?

When a pilot declares an emergency and is not radar identified, the appropriate transponder code to assign is 7700. This code is specifically reserved for emergency situations. It alerts air traffic controllers that the aircraft needs assistance, enabling them to prioritize and provide the necessary help.

Assigning this code allows controllers to quickly recognize the emergency status of the aircraft, even if it is not under radar identification, facilitating a timely response. This is critical for ensuring the safety of the aircraft and its occupants.

In scenarios where a pilot is experiencing a hijacking, the assigned code would be 7500, which is specifically designated for unlawful interference. If there are communications issues but no emergency situation exists, the code 7600 would be used for lost communications. A transponder code of 1200 is generally used for VFR (Visual Flight Rules) flights, which does not apply in the context of an emergency declaration.