Which of the following is NOT a mode of the UPX-29 IFF?

The UPX-29 Identification Friend or Foe (IFF) system is designed to enhance situational awareness by categorizing and identifying aircraft and other entities in the vicinity. The modes of UPX-29 include various operational parameters for tracking and identifying targets.

The key modes of UPX-29 encompass platform identification, which helps distinguish between different types of aircraft or vessels, and commercial air traffic identification, which specifically concerns civilian aircraft to prevent any potential friendly fire incidents. Altitude is often tracked as part of the system to provide additional context for the identified targets, particularly in distinguishing between the operational levels of various aircraft.

Speed, however, is not a mode of the UPX-29 IFF system. While speed can be an important characteristic in many military applications, it does not serve as a mode in the context of IFF operations. Instead, the focus of the IFF system is on identity and intents rather than the velocity of the aircraft. Thus, speed does not fall under the operational functions of UPX-29, making it the correct response to the question.