Naval Technology

Ultra Maritime completes first in-water MSARS sonobuoy trial in Scotland

MSARS is a G-Size sonobuoy designed to enhance multistatic detection and localisation over existing multistatic sonobuoy technologies.

Ultra Maritime has completed the first in-water deployment trial of its Multistatic Active Receive Sonobuoy (MSARS) in Scotland.

The company announced the test marks a step forward in anti-submarine warfare (ASW) capabilities for the UK, particularly in response to heightened activity in the North Atlantic.

The MSARS is a G-Size sonobuoy with a small form factor, developed to enhance multistatic detection and localisation of threat submarines and uncrewed underwater vehicles compared to existing technologies.

Specifically designed to operate from both crewed and uncrewed platforms, including Rotary Wing and Fixed Wing Uncrewed Air Systems (UAS), MSARS aims to improve flexibility and persistence in contested environments.

In March 2025, Ultra Maritime completed the Preliminary Design Review for MSARS, as part of a research and development programme funded by the UK Defence Science and Technology Laboratory (Dstl).

Dstl, an agency of the Ministry of Defence, supports the platform as part of the Atlantic Bastion programme, which seeks to broaden autonomous ASW capability for both UAS and crewed assets such as the Merlin Mk2.

According to Ultra Maritime, MSARS is developed to deliver better performance than current Royal Navy sonobuoy systems.

To speed up operational deployment and address evolving hybrid warfare challenges, the company is working with General Atomics to integrate MSARS and other G-size sonobuoys onto the MQ-9B SeaGuardian platform.

This integration is intended to expand operational reach, increase payload capacity, and enable distributed multistatic operations, potentially improving allied forces’ ability to detect and track undersea threats.

Reflecting on the progress, Ultra Maritime stated in a LinkedIn post, “We are proud to announce a major milestone for the future of anti-submarine warfare (ASW).

“This successful deployment of MSARS is another step in leading the transformation of ASW across air, surface and undersea domains.”

In February this year, the UK Ministry of Defence (MoD) awarded a £40m ($54m) contract to Ultra Maritime for the supply of sonobuoys to equip the Royal Navy’s Merlin Maritime Patrol Helicopter.