Ukrainian officials have shared details on plans to deepen interoperability between the country’s integrated air defence system and NATO’s air and missile defence infrastructure.
The air defence architecture for the alliance’s European membership is built around NATO’s Air Command and Control System (ACCS). ACCS is a common Command and Control (C2) system which can be tailored to the specific requirements of European alliance members. Each national replication of the ACCS architecture is responsible for providing the C2 of air operations, and the defence of national airspace and air approaches for European NATO members.
Each European NATO member using the ACCS architecture employs this to create a national Recognised Air Picture (RAP) generated by their accompanying ground-based air surveillance and fire control/ground-controlled interception radars, and other sensors. The Air Command and Control System is also responsible for providing the C2 backbone for NATO’s Integrated Air and Missile Defence System (NATINAMDS). A key difference between the ACCS and NATINAMDS is that the latter encompasses all the alliance sensors, effectors and connectivity used to perform the air and missile defence missions. The ACCS, on the other hand, is the overarching C2 system.
National RAPs are shared with one, or more, of three NATO Combined Air Operations Centres (CAOC). The CAOC at Torréjon airbase, northwest of Madrid, is responsible for the safeguarding of the airspace and air approaches of NATO European members south of the Alps. The CAOC at Uedem airbase, western Germany, performs a similar function for NATO airspace and air approaches north of the Alps. A third CAOC was opened at Bodø airbase, northern Norway, in October 2025 and is responsible for air operations in the high north. NATO has a Deployable ACCS (DACCS) architecture for out-of-area operations based at Poggio Renatico airbase, northern Italy. The DACCS performs CAOC functions and is joined by the Deployable Air Reporting System (DARS), also based at Poggio Renatico. The DARS supports air defence performing similar functions to an IADS control and reporting centre. The CAOCs, DCAOC and DARS are all subordinate to NATO’s Allied Air Command headquartered at Rammstein airbase, western Germany.
Links
Connectivity is at the heart of NATO’s air command and control system, and is indispensable for sharing the RAP, C2 data and federating the disparate national IADS and their accompanying ACCS replications. Standard datalinks used to exchange track, tactical data and voice traffic include NATO’s Link-11/22 (two megahertz/MHz to 29.9MHz, 225MHz to 399.975MHz) and Link-16 (960MHz to 1.215 gigahertz/GHz) encrypted Tactical Datalinks (TDLs). Secure Satellite Communications (SATCOM) networks are employed including France’s Syracuse X-band (7.9GHz to 8.4GHz uplink/7.25GHz to 7.75GHz downlink) and Ka-band (14GHz uplink/10.9GHz to 12.75GHz downlink), and Italy’s SICRAL (Sistema Italiano per Comunicazioni Riservate ed Allarmi/Italian System for Confidential Communications and Warning) constellations. SICRAL provides Ultra High Frequency (399MHz to 470MHz), X-band and Ka-band links. NATO’s Federated Mission Networking (FMN) framework lets alliance members configure their local military communications systems such as local area networks to meet alliance stipulations. Domestic networks meeting FMN standards can also be employed for ACCS networking. Other conduits include national, secure telecommunications infrastructure. This multiplicity of links ensures no single point of failure exists for ACCS networking, helping to build resilience.
Enter Ukraine
Armada understands that Ukrainian air defence officials are contemplating how the country’s IADS could be networked into the wider ACCS and NATINAMDS ensembles. Ukrainian officials have shared that Link-16 would play a key role in federating the Ukrainian IADS into the alliance air defence infrastructure. Ukraine already has access to Link-16 connectivity, so much of the groundwork has already been performed therein. However, as noted above, ACCS does not rely solely on one conduit. Ukrainian officials shared that they would also exploit secure SATCOM connectivity and secure digital channels using conventional communications. Other important steps being taken by Ukrainian air defenders include the adoption of NATO air defence standards and protocols which will greatly ease the intermeshing of ACCS and Ukraine’s IADS in the future. For example, another aspect of this integration focuses on Ukraine’s adoption of NATO identification friend or foe protocols like Mode-5. Mode-5 is the militarised, secure version of the civilian Mode-S secondary surveillance radar interrogation and response system.
Ukraine is not yet a NATO member, but this should not stop the integration of the country’s IADS with its alliance counterpart. For example, the Swiss Air Force’s FLORAKO (Florida Radarersatz Andockbares Kommunikationsoptimiertes System/Radarluftlagesystem Kommunikationssystem/FLORIDA Radar Replacement Dockable Communication-Optimised System/Radar Air Situation System Communication System) links into ACCS. Florida was the name of the IADS that FLORAKO replaced and was chosen by the Hughes Aircraft Corporation which provided the system. FLORAKO connects into the ACCS architecture using conduits like Link-16 enabling the Swiss Air Force to share relevant tactical data and RAP imagery with NATO.
The FLORAKO arrangement provides a useful template at the policy level for Ukraine’s approach. Moreover, NATO and Switzerland can enjoy a level of air defence synergy and interoperability despite the latter being outside the alliance. Ukraine arguably still has some way to go until she becomes a NATO member, but this need not impede the integration of the country’s IADS within NATO’s larger air defence posture. The integration will be a major benefit to safeguarding alliance skies and providing advanced warning of air threats crossing Ukrainian territory potentially threatening alliance members.
by Dr. Thomas Withington
