BAE Systems to equip KAI’s KF-21 with Friend or Foe system

Image courtesy BAE Systems

The latest Identification Friend or Foe (IFF) system enables enhanced decision-making capabilities to distinguish between allied forces and potential threats in contested scenarios.

Made for tactical aircraft, the CIT design ensures ongoing versatility to meet current and future mission requirements and support the warfighter in the evolving battlespace. Its open-system architecture allows for software upgrades, reducing the risk and cost associated with hardware modifications. It provides advanced, multifunction capabilities while supporting the latest crypto, anti-jam and cybersecurity resilience requirements.

“The APX-127 Combined Interrogator Transponder will equip the KF-21 aircraft with state-of-the art IFF to help bolster the Republic of Korea’s national defence strategy,” said Seth Guanu, Combat Identification Products programme area director at BAE Systems. “This new system gives fifth-generation fighter pilots an edge in air superiority missions and allows them to maintain interoperability with US and coalition partners.”

With the same form factor, the AN/APX-127(V)1 is a drop-in replacement for the AN/APX-126(V) CIT currently fielded on the KF-21. It is Mark XIIB IFF certified with Mode S and Mode 5 for secure and encrypted data exchange. The upgraded system enhances situational awareness for warfighters with additional receive channels for passive acquisition of Mode 5 Level 2 and Automatic Dependent Surveillance – Broadcast In to detect and identify friendly aircraft in complex and dynamic environments. 

Leveraging advanced technology and architecture, BAE Systems’ next-generation IFF solutions address obsolescence and increase processing capacity to enable future capability needs. With more than 80 years of experience, the company has delivered over 1,500 interrogators, 6,000 combined interrogator transponder systems and 16,000 transponders. IFF products are available for all service branches and support the US and coalition forces in air defense, weapon systems, air traffic control and range instrumentation. 

Work on the AN/APX-127(V)1 CIT is performed at BAE Systems’ facilities in Greenlawn, New York and Austin, Texas. The KF-21 CIT units are expected to be delivered to KAI for integration and certification in 2026.