TRML-4D: cutting-edge radar shielding Ukraine’s skies

Content

1. What is TRML-4D?

2. How TRML-4D radar works

3. TRML-4D characteristics

4. TRML radars in Ukraine

5. What else is known about the TRML-4D radar?

What is TRML-4D?

TRML is a family of air defense radars initially developed by Telefunken and now produced by Hensoldt. The name translates from German as Telefunken Mobile Airspace Surveillance Radar (German: Telefunken Radar Mobil Luftraumüberwachung).

The latest version, TRML-4D, which Ukraine is using, was unveiled at the Eurosatory exhibition in 2018. The first customers received this radar in 2020.

TRML-4D can detect, track, and classify all types of aerial threats, including cruise missiles, drones, as well as maneuvering aircraft and helicopters flying at low altitudes. The radar can simultaneously track up to 1,500 targets within a 250 km radius. Its guidance system can distinguish between friendly and enemy aircraft and detect and counteract jamming attempts.

Defense Express calls the TRML-4D the most advanced in its class. Hensoldt CEO Thomas Müller describes it as "the best medium-range radar in the world today." Meanwhile, Bloomberg states that the radar "helps Ukraine intercept more than 90% of enemy aircraft over its skies."

How TRML-4D radar works

"The core of this fully digital radar is an active phased array antenna made of gallium nitride. Simultaneous multi-beam and Doppler signal processing allows it to operate in complex conditions with interference and high target density," states Defense Express.

The array effectively detects small and low-observable targets with a radar cross-section of 0.01 square meters. Experts consider this figure very high, significantly outperforming modern cruise missiles and stealth aircraft.

The developer emphasizes the radar's ability to rapidly create target tracks. Additionally, the manufacturer guarantees the reliability of the radar components and claims they operate without failure in 24/7 mode.

The TRML-4D radar is mounted on an 8x8 wheeled chassis, making it transportable by A400M or C-130 aircraft.

The TRML-4D radar system was primarily designed for use with the IRIS-T air defense system. It serves as the primary detection tool for the IRIS system, which also includes several self-propelled launchers and a fire control center. In cooperation with the IRIS-T system, the radar enables the interception of aerial targets at distances up to 40 km and altitudes up to 20 km.

Regarding target detection range, while the radar's instrumental range is 250 km, a fighter aircraft is detected at a range of 120 km, and tactical missiles at 60 km. In one of the videos showcasing the TRML-4D's capabilities, Hensoldt demonstrated the tracking of a target such as an artillery shell at an effective range of 96 km.

However, the German radars can operate independently of the IRIS system. Modern NATO radars are integrated into a unified network, enabling information exchange and the creation of a single information field. Formally, according to Defense Express, the TRML-4D can also work in the NASAMS air defense system, which has its own AN/MPQ-64 Sentinel radar, and can transmit information to Soviet-made air defense systems. This creates a comprehensive picture of the airspace, with all radars, launchers, command posts, and radars functioning within a unified system. This approach ensures high efficiency, maximum situational awareness, and a short response time.

TRML-4D characteristics

• Frequency – C-band,
• Instrumental range – 250 km,
• Tracking range – 120+ km (fighter jet), 60+ km (supersonic missile),
• Maximum detection altitude – 40 km,
• Number of targets – up to 1500,
• Minimum RCS of the target: 0.01 sq. m,
• Deployment time – 10 min,
• Price – approx. 17 million euros.

TRML radars in Ukraine

The first agreement regarding the supply of 4 TRML-4D radars to Ukraine was signed back in 2022. In October of the same year, the first radar system was delivered to Ukraine.

"The situation in Ukraine requires swift and decisive action. Thanks to our serial production line and the dedication of our employees, we can supply these systems to protect the population in the shortest possible time," said Hensoldt's Thomas Müller at that time.

In 2023, it was announced that 5 more TRML-4D radars would be supplied to Ukraine. These radar systems were also included in subsequent arms packages, and it was reported that Germany would provide Ukraine with 6 more radars by 2024.

As of the beginning of 2025, the German government officially reports the delivery of 16 TRML radar systems to Ukraine. However, it is noted that decisions made do not yet mean that the radars are already in Ukraine.

"Some deliveries require modernization, production of weapons may still be ongoing, or training of crews may be taking place," states the German government website.

What else is known about the TRML-4D radar?

Regarding the cost of the radars, in 2023, manufacturers reported that the contract for supplying 6 systems to Ukraine exceeded 100 million euros. Therefore, the approximate cost of one TRML is around 17 million euros.

Overall, defense company Hensoldt reported receiving orders worth "significantly over one billion dollars" in the first half of 2024. Although the share of TRML-4D radars in these orders was not disclosed, the company is so confident in the demand for these radars that it produces systems in advance – before receiving actual orders, as Bloomberg reported.

In addition to Ukraine and Germany, these state-of-the-art radars are also used by the Netherlands, Lithuania, Malaysia, and Thailand. In 2024, contracts were signed to supply radars to Latvia and Slovenia as part of the European Air Shield program.

However, so far, the radars have been used in combat conditions, not on training grounds with decoys, only by Ukraine. The real military use, with the corresponding threats, has demonstrated the effectiveness of the systems, according to experts. For example, Defense Express reported that "the radar performs excellently in the hands of our military" and noted its effectiveness in detecting Russian aircraft.