Bulgaria Tests C4ISR Capabilities in NATO’s Largest Interoperability Drill

Bulgarian military personnel took part in NATO's "Coalition Warrior Interoperability Exercise" (CWIX) 2025, held from June 2 to 20 in Bydgoszcz, Poland. The large-scale exercise brought together experts and systems from NATO member states and partner countries, aiming to enhance the technical and operational interoperability of command and control structures across the alliance. Bulgaria was among the active participants, showcasing capabilities through a combined effort by the Ministry of Defense and the Armed Forces.

CWIX is a recurring exercise coordinated by NATO’s Allied Command Transformation and sanctioned by the NATO Military Committee. Its purpose is to test and refine C4ISR systems – command, control, communications, computers, intelligence, surveillance, and reconnaissance – in a secure environment that mirrors the complexities of modern multi-domain operations. These include systems supporting NATO Response Force and Combined Joint Task Force missions. This year’s edition emphasized interoperability in the context of digital transformation and the integration of operations across land, air, sea, cyber, and space.

The Bulgarian contingent was led by Colonel Krasimir Yordanov from the CIS Directorate at the Defense Headquarters. Information security responsibilities were handled by a representative of the Ministry of Defense’s Information Security Directorate. Bulgaria’s participation was organized and technically supported by Joint Forces Command, Mobile CIS, and the Communication and Information Support and Cyber Defense Command. Their teams deployed communication and information systems in support of NATO’s Federated Mission Networking – FMN CS – and carried out successful validations of services and applications within that framework.

Bulgarian Land Forces contributed with both personnel and equipment, focusing on the deployment and testing of their Harris C2 system in operational scenarios under the "LAND" and "MIP" (Multilateral Interoperability Program) domains. Their activities revolved around command and control operations at the tactical level, ensuring systems could function in concert with allied structures. Representatives from the Air Force and Navy were also embedded in the exercise’s analytical group, where they validated tests in key domains such as air operations, maritime activities, tactical data links (TDL), and cyber defense.

On June 18, the CWIX 2025 exercise hosted its High-Level Guest Day, attended by senior officials from participating nations. Representing Bulgaria was Lieutenant General Yavor Mateev, Military Representative of the Chief of Defense at the country’s NATO delegation. During the visit, guests were shown demonstrations of how various NATO and national command and control systems can effectively interoperate in federated network environments and multi-domain settings.

CWIX 2025 once again served as a practical platform for the Alliance to fine-tune its digital infrastructure and operational cohesion. Bulgaria's role underscored its commitment to NATO’s collective readiness and its growing capability to contribute to joint operations across the full spectrum of defense domains.