Japan plans the purchase of four C-2 SOJ electronic warfare aircraft to replace its unique EC-1.

On December 23, 2024, the Japanese Ministry of Defense shared new information about the development of a stand-off electronic warfare (SOJ) variant of the Kawasaki C-2 transport aircraft, designed to replace the EC-1, an unique electronic warfare aircraft in service since 1986. This initiative, which will involve the purchase of four aircraft, aims to enhance the Japan Self-Defense Forces' (JSDF) capabilities with long-range jamming to disrupt enemy systems while ensuring operational safety.

The program plans to procure four C-2 SOJ aircraft, using technologies from previous systems, including the J/ALQ-5 electronic jamming device and advanced radio wave measurement systems. (Picture source: Japan MoD)

The Ministry of Defense (MoD) initiated the C-2 stand-off electronic warfare (SOJ) program in fiscal year 2020. Development is divided into two phases. The first, spanning 2020 to 2026, focuses on establishing data link jamming capabilities and integrating a multi-electronic warfare platform. The second phase, from 2023 to 2032, aims to refine and operationalize these technologies. The program plans to procure four SOJ aircraft, relying on domestic development to address national defense requirements while maintaining operational secrecy. The platform incorporates technology from previous systems, including the J/ALQ-5 electronic jamming device and advanced radio wave measurement systems.

The EC-1, which the C-2 SOJ is intended to replace, is a dedicated electronic warfare platform derived from the Kawasaki C-1. Developed in 1983, the EC-1 is equipped with the J/ALQ-5 electronic countermeasure (ECM) system, later upgraded to the J/ALQ-5 Kai, Toshiba ELINT systems, and supplementary American ECM and ELINT avionics. The aircraft's airframe modifications include a black bulbous nose, tail radome, and antenna fairings for radar and communication jamming equipment.

Testing began in December 1984, and the aircraft entered service in June 1986. Based at Iruma Air Base, the single-unit EC-1 supports training and operational testing for the Japan Air Self-Defense Force (JASDF). It can detect and jam radar and communication signals and deploy chaff pods when required. Although it remains in service, the EC-1 is being phased out as Japan transitions to more advanced systems, mainly based on the newer C-2 aircraft.

Despite being initially designed as a transport aircraft, the C-2 has been adapted for multiple roles, including electronic intelligence gathering as the RC-2. Testing demonstrated its ability for semi-level takeoffs and landings on unpaved surfaces, enhancing its operational utility for emergency operations. The development of the C-2 began in the early 2000s under the designation CX, and to reduce expenses, the C-2 shares components with the Kawasaki P-1 maritime patrol aircraft.

In addition to this new electronic warfare variant, the C-2 could soon be armed with long-range missiles, including a modified Type 12 surface-to-ship missile, as well as the US-made AGM-158 Joint Air-to-Surface Standoff Missile (JASSM). These missiles could extend the C-2’s operational range to over 11,000 kilometers, supporting counterstrike capabilities as outlined in Japan's earlier Defense Buildup Program.

Like the future C-2 SOJ, the EC-1's airframe modifications include a black bulbous nose, tail radome, and antenna fairings for radar and communication jamming equipment. (Picture source: Twitter/アユザック)

The Kawasaki C-2, a domestically developed military transport aircraft, is the platform for the new stand-off electronic warfare (SOJ) variant. The aircraft measures 43.9 meters in length, has a wingspan of 44.4 meters, and a height of 14.2 meters. It is powered by CF6-80C2 engines, capable of achieving speeds up to Mach 0.82, and can carry up to 20 tons over a range of approximately 7,600 kilometers.

The C-2 was designed to replace the C-1 and complement the C-130H Hercules in the JSDF's fleet. It features a payload capacity of 36 tons, a glass cockpit, fly-by-wire controls, and a tactical flight management system. The aircraft is capable of transporting large cargo such as MIM-104 Patriot missile systems and H-60 helicopters and has been deployed for operations including disaster relief and domestic missions since entering service in 2016.

Japan plans to procure four C-2 Stand-Off Jammer (SOJ) aircraft to expand its electronic warfare capabilities and address evolving national defense requirements, a notable increase compared with the purchase of a single EC-1. The SOJ, based on the larger and more advanced C-2 airframe, is designed to disrupt and neutralize enemy radar and communication systems from a safe distance, allowing for operations beyond adversaries’ threat ranges.

This program reflects Japan's strategy to modernize the Self-Defense Forces’ capabilities in the electromagnetic spectrum and enhance operational readiness across multiple areas. The SOJ complements other developments, such as the RC-2 and missile-equipped configurations, as part of efforts to adapt to changing security scenarios. The C-2 platform's design addresses broader operational requirements compared to the single-unit EC-1, which was developed in the 1980s as a modified C-1 transport for electronic warfare training and testing rather than frontline missions.