Showing a comprehensive set of naval capabilities at UDT 2025, the exhibition provided Aselsan the opportunity to unveil the latest developments in the underwater domain, with a focus on sonar technology, unmanned vehicles and key equipment for both manned and unmanned underwater platforms
The 50th anniversary celebration year of Aselsan as leading defence company in Turkey and among the biggest defence companies will register key developments in the underwater domain, focusing mainly in expanding sonar technology for both surface and underwater applications, but also unmanned underwater vehicles and mission suites for submarines.
Aselsan is expecting to receive in 2025 the first contract for its Düfas low-frequency towed active/passive sonar system, the first national anti-submarine warfare solution for surface platforms, which projects the company in the towed-array sonar domain for combatant platforms on the international market.
Designed for long-range detection and tracking of underwater threats, with optional integrated torpedo countermeasure capabilities, the Düfas 100/LR (Long Range) active/passive variable depth sonar (VDS) suite is expected to be ordered to equip the latest generation Istanbul-class frigates under construction for the Turkish Navy. The first-of-class Istanbul frigate is equipped with the same torpedo defence suite – based on the Hizir 100-N towed array and Zoka acoustic decoys -already installed on the Ada-class corvettes but the following frigates of that class will receive the new sonar suite.
Consisting of a low-frequency towed active array and a low-frequency towed passive triplet array, with separate winches for each array, common signal processing and power cabinets, operator consoles and optional torpedo countermeasures capabilities, the Düfas provides, according to Aselsan, long range automatic target detection and localization capabilities in active mode, long range automatic torpedo detection, tracking and classification capabilities in passive mode, alongside 360 degrees omni-directional transmission and bi-static/multi-static sonar architecture. Able to operate and survive at high speeds and high sea state conditions, the new sonar suite incorporates a triplet towed array for resolving port/starboard ambiguity, state-of-the art signal processing, and the optional torpedo countermeasures capability. The latter includes pneumatic launchers for expandable decoys together with towed acoustic decoys.
The Düfas active/passive VDS comes together with the Fersah 100-N/MF hull-mounted sonar also provided by Aselsan, in the mid-frequency with high source level and array directivity. The latter has active and passive alongside mine like object avoidance modes.
Aselsan is also developing the Düfas 100-CU compact variable depth sonar model which comes equipped with dual winches and towed arrays but with an overall reduced footprint to be installed on unmanned surface vehicles. The compact model is expected to complete qualification and be ready for production in 2026.
In parallel to new generation sonar suites for surface combatants, Aselsan is expanding its sonar suite solution package for submarine with the addition of a towed array. Designed to cope with latest requirements being set by the Turkish Navy, Aselsan conducted in-house risk reduction activities on the new solution to be ready for the Turkish Navy to order its development.
This in addition to the remaining components of a next generation submarines sonar suite, which initial national iteration was developed for the mid-life upgrade programme of the Turkish Navy’s Type 209-1400 Preveze-class submarine.
Under an internal development programme, Aselsan is also working on the new national aselBUOY 100P passive directional sonobuoy in NATO A-size for both manned and unmanned aerial platforms.
The other portfolio solution where Aselsan has already been successful is the autonomous underwater vehicle (AUV) segment where the recently developed Deringöz has already gained contracts from both the military and civil markets. A next-generation AUV developed for mine countermeasures, exploration, and undersea surveillance with deep-sea operation capabilities, the Deringöz comes in two different versions with respectively a 600- and 300-meters depth rating. The first model known as Deringöz 100M/600 has been contracted to equip the next generation mine countermeasures vessels for the Turkish Navy. Each vessel will be equipped with two AUVs each incorporating a sensor suite for mine countermeasure including side scan sonar, optical sensor, wireless and acoustic communication suites. With a 600 meters depth rating and an 8-hours nominal (which can reach 24 hours with two extra batteries), the Deringöz AUV 100/600 has a customizable mission suite and can reach maximum and nominal operational speeds of respectively 5.5 and 3 knots. The other contract is for the Deringöz 100M/300 model and comes from the Oil&Gas sector.
At UDT 2025 Aselsan also showed the Ares 2-SC 200 Radar Electronic Support Measure for submarine applications and Acrobat X38-S submarine satellite communication terminal, alongside Radar Warning Receiver/GPS Antenna Radome and ED Antenna, providing enhanced signal reception and electronic countermeasure resilience, and the radar, electronics and weapon package for the Istif-class frigates.
Aselsan also offers a DGPS Antenna for high-precision navigation and positioning for naval platforms, IdentIFF Systems including the IFF responder and short-to-medium range interrogator, ensuring secure identification of friendly force, and 9671 V/UHF & 9671 HF naval radios, the next-generation software-defined radios (SDRs) enabling secure, high-speed data and voice communications across naval fleets.
Photos by L. Peruzzi