Home / Military / Air Force / US and UK Airforce deploying Next Generation Identification Friend or Foe (IFF) technology for rapid engagement of enemy aircraft, and reduce risk to friendly aircraft.

US and UK Airforce deploying Next Generation Identification Friend or Foe (IFF) technology for rapid engagement of enemy aircraft, and reduce risk to friendly aircraft.

IFF (Identification Friend or Foe) is the military designation of the Air Traffic Control (ATC) System that is used to identify and track military aircraft. It enables military and civilian air traffic control interrogation systems to identify aircraft, vehicles or forces as friendly and to determine their bearing and range from the interrogator.

Identification Friend or Foe is an identification system designed for command and control. It is particularly important in the age of supersonic aircraft and missiles that make it impossible to rely on visual identification methods; and without such systems modern command and control would almost be impossible. Ensuring the capability in an ever more complex battlespace is crucial.

As threats of military conflict continue unabated from its northern neighbor, South Korea’s military officials have signaled the need to upgrade their nation’s ability to quickly determine whether incoming aircraft are friend or foe.

In a procurement package announced Wednesday, South Korea’s Defense Acquisition Program Administration revealed that has launched an Identification Friend or Foe (IFF) program that implements homegrown research and design assets, as well as overseas software and firmware technology purchases, according to Yonhap News.

The IFF system consists of an airborne transponder and a ground (or airborne) interrogator. The system measures the distance and heading to the aircraft, and the transponder encodes identification and position information into the response.

The 1994 shooting down of 2 US Black Hawk choppers by USAF F-15’s over the enforced Iraqi No-Fly Zone, is an example of what happens in case the codes are set wrong or not detected properly.

Identification Friend or Foe [IFF] procedures are the primary positive means of aircraft identification in Air Defense operations. Proper use of IFF procedures facilitates rapid engagement of enemy aircraft, conserves Air Defense assets, and reduces risk to friendly aircraft. Any time a plane flies, pilots put a code into their IFF system which others can identify as a friendly aircraft.

Combat Identification is the process of attaining an accurate characterization of detected objects in the battle space to the extent that a high confidence, timely application of tactical options, and weapons resources can occur. Depending on the situation and the tactical decisions that must be made, this characterization will be at least, but may not be limited to, “friend,” “enemy,” or “neutral.” Combat identification functions encompass cooperative and non-cooperative identification capabilities.

Reliable and secure positive identification (ID) systems are essential elements of battle management in the naval environment. In addition to distinguishing friend from foe for weapons employment, the Navy requires secure, jam resistant Identification Friend or Foe (IFF) systems for battle group air defense management and air traffic control. Identification is multifaceted and includes information received from several sensors (both cooperative and non-cooperative systems).

The cooperative combat identification capability in surface ships is provided by the Mark XIIA Interrogation Friend of Foe (IFF) system, a challenge and reply (or “Q and A”) system. The current inventory of IFF interrogators and transponders are antiquated, and the procurement of new Digital Interrogators (AN/UPX-37) and Digital Transponders is underway.


IFF Mode 5

IFF Mode 5 is the most recent implementation of the system. Mode 5 IFF is the next-generation encrypted data link between interrogators and transponders to confirm an aircraft is friendly, and provides information assurance for MK XIIA IFF interrogators and transponders using Mode 4 and Mode 5.

The Mode 5 waveform uses modern modulation, coding, and cryptographic techniques to overcome performance and security limitations in the current Mark XII waveform. Additionally, Mode 5 systems provide expanded data handling capabilities to securely pass GPS position and other extended data. The new system uses interference reducing spread spectrum techniques which allow the additional data transmissions to be overlaid on the existing ATC system frequencies without increased interference. All legacy modes and Mode 4 operational capability will be retained in order to facilitate an orderly transition to the new Mode 5 IFF waveform.

The new Mode 5 interrogators and transponders have been in development for the last six years with companies including BAE, Raytheon, and Telephonics, all producing Mode 5 systems for use on military aircraft (e.g., AN/APX-119 and AN/APX-123). BAE and Raytheon also produce Mode 5 cryptographic appliqus that store the secret keys and will be used to support flight-line testing of the aircraft systems. BAE is manufacturing a KIV 78 crypto appliqu and Raytheon is manufacturing a KIV 77 crypto appliqu. The Mode 5 interrogators, transponders, and test support equipment are now entering pilot production and the U.S. military is now in the system integration and technical evaluation stage for the new systems and test support equipment.


Raytheon’s KIV 77

The spoofing or mimicking of IFF technology by more sophisticated potential opponents was identified as a concern by the US Air Force as far back as the 1990s. The potentially disastrous consequences of a near peer competitor being able to spoof the then generation of IFF transponders was acknowledged, and advanced cryptography was seen as the best solution.

Devices such as the KIV-77 – which in essence allows the user to input a secure cryptographic key that is transmitted as part of the wider IFF transponder signal ensuring its authenticity to other users – were designed to overcome those concerns. Raytheon made the first deliveries of the device in 2010.

In today’s environment the major concerns for IFF are electronic interference and key loading (the secure distribution of the correct cryptographic keys). According to Raytheon these two areas are the most challenging issues for secure IFF.

The KIV-77 is Type 1 certified by the National Security Agency and provides information assurance for both legacy Mode 4 and new Mode 5 IFF equipment.

“KIV-77 is NSA certified and incorporates all the new features of the Mode 5 system, providing reduced size, weight, and power consumption (SWaP) over the older Mode 4 system,” Whiston says. In this way Raytheon argues that it futures proofs the system for the next generation of aircraft and missile technology.


The US Air Force has contracted Raytheon to provide secure identification friend-or-foe (IFF) equipment

The US Air Force has contracted Raytheon with a $42.8 million follow on order of secure identification friend-or-foe (IFF) equipment as part of continuing efforts by the service to increase the security and surety of its IFF systems.


“The Identification Friend or Foe system is critical to the warfighter as it positively identifies friendly forces, reduces potential for fratricide and increases situation awareness,” says Frank Whiston, IFF director, Tactical Communications Systems, Raytheon Space and Airborne Systems (SAS).


In this case, the US Air Force contract was let by the Air Force Life Cycle Management Center at Joint-Base San Antonio, Texas and was for the provision of KIV-77 Mode 4/5 cryptographic applique systems by Raytheon SAS in Aberdeen, Maryland.


“The KIV-77 is the Mode 5 Crypto Applique device that provides the security function of the IFF system. This recent contract award was a follow-on IDIQ from USAF to provide KIV-77 Crypto Appliques to international and domestic operators,” explains Whiston.



As forces like the US Air Force prepare to face a return to peer or near-peer adversaries, technologies such as IFF remain a key capability to allow them to dominate the battlefield. With companies such as Raytheon continuing to push the envelope in IFF technologies, the battle is already half won.


UK  £260M job-sustaining contract for advanced identification system

The Ministry of Defence has awarded a £260 million contract to supply the UK’s with the next generation of secure Identify Friend or Foe (IFF) technology. The Mode-5 system will be installed on the Royal Navy’s Type 45 Destroyers.

The system, called Mode-5 and developed for the MOD by UK-based company Leonardo, uses advanced cryptographic techniques and world-leading electronic technology to allow UK land, sea and air units to quickly identify friendly forces and operate safely alongside NATO allies across any battlefield.


Mode-5 IFF has been designed to give UK units a clear and secure view of potential threats and targets, providing a powerful cyber shield against jamming and interference intended to reduce vital situational awareness.


The contract will allow Leonardo to install the system in more than 350 units ranging from Royal Air Force’s Sentry aircraft to the Royal Navy’s Type 45 anti-air destroyers and the British Army’s High Velocity Missile (HVM) multiple launcher system.


Less-advanced IFF systems have been used by nations all over the world since the 1940s. Mode-5 uses the same basic ‘call-and-response’ method as earlier systems, but significantly improves on them. Crucially, the system can easily interface with allied forces, reducing the risk of ‘friendly fire’ incidents between UK units and the units of other allies.


Defence Equipment and Support (DE&S) Chief Executive Officer Tony Douglas said: Advances in digital and cyber warfare mean that it’s never been more important for UK military forces to have the kind of confidence in their situational awareness that Mode-5 IFF instills. The installation of this world-leading system will continue to give our fighting men and women a decisive edge on operations.



Being more cryptographically secure than its predecessors, the Mode 5 system counters exploitation and deception while delivering resistance to Electronic Counter Measures (ECM). As in the US, the UK equipment was fitted with Raytheon SAS KIV-77 Mode 5 Cryptocomputers.


AWACS Next Generation Identification Friend or Foe (NGIFF) Program

Airborne Early warning and control (AWACS) aircraft provides a real-time picture of friendly, neutral, and hostile air and maritime activity under all kinds of weather and above all kinds of terrain. Information collected by AWACS can be transmitted directly from the aircraft to other users on land, at sea or in the air. In air-to-air combat, AWACS systems can communicate with friendly aircraft, extend their sensor range and give them added stealth, since they no longer need their own active radar to detect threats.The US  E3 AWACS  has proved to be a key to victory for the United States in the 1991, 2001, and 2003 campaigns.

The Next Generation Identification Friend or Foe (NGIFF) Program provides AWACS with enhanced IFF interrogator operation to add a more secure Mode 5 capability. NSA declared IFF Mode 4 unsecure and obsolete on 5 Nov 2003. The new Mode 5 interrogation capability extends the effective range of the AWACS interrogator, while helping discriminate against closely spaced cooperative targets.

NGIFF will also integrate Mode S, a civilian air traffic control capability residing in the NGIFF hardware, as funding allows.

Coupled with an IFF interrogation system, the radar will be capable of detecting, identifying and tracking enemy and allied low-flying aircraft even in the presence of ground clutter signals.




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