Which IFF mode is used to identify the mission of a squawking unit?

Mode 1 is specifically designated for identifying the mission of a squawking unit in the Identification Friend or Foe (IFF) system. This mode provides a code that communicates specific information about the mission of the aircraft, such as whether it is engaged in a combat operation or a training exercise.

Understanding the functionality of the different IFF modes is crucial. Mode 1 distinguishes itself by being utilized primarily by military units to relay mission-specific information, offering an insight into operational intentions. Other modes, such as Mode 2, are used for specific identification primarily relating to the aircraft's own identification number, while Mode 3 is used for general air traffic control and civilian identification, typically representing a standard squawk code. Mode 4 is often utilized for secure identification in encrypted systems.

Thus, Mode 1 is directly associated with conveying mission details, making it the correct choice for identifying the mission of a squawking unit.