Switzerland Completes Successful TRML-4D Radar Trials for Next-Gen Air Defence System

Switzerland has taken a major step towards enhancing its air defence capabilities by successfully completing crucial trials of the TRML-4D radar. These tests are part of the country’s development of a new medium-range ground-based air defence (GBAD MR) system, which is expected to play a key role in protecting Swiss airspace from modern aerial threats.

The radar trials, conducted by the Swiss Federal Office for Defence Procurement, armasuisse, in collaboration with the Swiss Armed Forces, took place between 31 March and 11 April 2025. Two key locations were selected for testing — the federally-owned Homberg site and the Emmen aerodrome — due to their diverse terrains and relevance to Switzerland’s unique geographical conditions.

Realistic Testing in Swiss Terrain

The TRML-4D radar was tested under realistic and operationally relevant conditions. The main focus of the trials was to assess the radar’s ability to detect, classify, and track various airborne targets, while also ensuring that it operates without interfering with civilian systems like weather radar.

Several aircraft, including the PC-12, PC-7, F/A-18 jets, and helicopters, were used to simulate various flight profiles, speeds, and altitudes. In addition to live aircraft, a radar target simulator was deployed to create simulated targets with different radar cross-sections and velocities, mimicking modern aerial threats such as cruise missiles.

Importantly, the radar emits non-ionising radiation (NIR), and armasuisse confirmed that the levels of electromagnetic radiation remained within safe limits, posing no health risk outside the radar’s security zone.

TRML-4D Radar – Core of Swiss Medium-Range Air Defence

The TRML-4D is a cutting-edge, multi-functional radar system developed by HENSOLDT, known for its high detection accuracy, fast target acquisition, and simultaneous tracking of multiple airborne threats. It operates in the C-band frequency range and uses advanced AESA (Active Electronically Scanned Array) technology.

Key Specifications of TRML-4D Radar:

• Detection Range: Over 250 km for aircraft and missiles

• Target Tracking: Capable of tracking up to 1,500 targets simultaneously

• Radar Technology: AESA-based with rapid beam steering

• Mobility: Mounted on mobile platforms for quick deployment

• Weather Resilience: Effective performance even under adverse weather conditions

• 360-Degree Coverage: Provides full spherical situational awareness

This radar will be a central sensor in Switzerland’s new GBAD MR system and is a vital part of the country’s Integrated Air Defence strategy, aiming to defend against medium-range threats, including stand-off weapons and cruise missiles.

Replacing Outdated Air Defence Systems

Switzerland’s current air defence systems, such as the shoulder-launched Stinger missiles and legacy medium-range anti-aircraft artillery, are no longer sufficient against today’s high-speed, high-altitude threats. The GBAD MR project, valued at CHF 660 million, is therefore critical to closing this operational gap.

As part of the program, Switzerland plans to acquire four or five IRIS-T SLM surface-to-air missile systems from Diehl Defence of Germany. These advanced systems are designed for highly accurate interception of aerial threats and will work in tandem with the TRML-4D radar.

Contract finalization is expected by the third quarter of 2025. The procurement is also aligned with the European Sky Shield Initiative, a multinational effort to strengthen collective European air defences.

Strengthening Swiss Air Sovereignty

Once fully operational, the GBAD MR system will significantly strengthen Switzerland’s ability to maintain air sovereignty, providing a modern and mobile solution to counter evolving aerial threats. It also demonstrates Switzerland’s commitment to investing in reliable and future-proof defence technologies to protect its citizens and territory.

By completing the TRML-4D radar trials successfully, Switzerland has moved one step closer to deploying a comprehensive and state-of-the-art medium-range air defence system that can stand up to the challenges of modern warfare.