What code is assigned to an aircraft experiencing a loss of two-way radio communication?

The code assigned to an aircraft experiencing a loss of two-way radio communication is 7600. This specific code is part of the standard transponder codes used in aviation for various situations. When a pilot is unable to communicate with Air Traffic Control (ATC) due to radio failure, they set their transponder to 7600, which alerts ATC to the communication issue.

Setting the transponder to 7600 allows ATC to provide the appropriate support and establish visual separation in case the aircraft needs to divert or make an emergency landing. This code is universally recognized and helps maintain the safety and efficiency of air traffic operations by indicating the specific nature of the problem.

In contrast, other transponder codes serve different purposes: 7700 is designated for general emergencies, 1200 is used for VFR (Visual Flight Rules) operations, and 4000 does not have a specific use in the context of transponder codes. By maintaining a standardized set of transponder codes, the aviation industry can ensure that all pilots and controllers utilize an effective communication system in managing air traffic, especially in emergencies.