BAE Systems' Herne extra-large autonomous underwater vehicle is on course to become the first platform of its kind certified under Lloyd's Register's Unmanned Marine Systems Code, marking a significant milestone in establishing recognised assurance standards for large uncrewed submersibles, and one with wide implications for naval architects and the defence maritime sector.

Herne is designed to deliver extended naval operations through a high degree of modularity and flexibility, enabling the platform to be rapidly adapted to meet evolving mission requirements through versatile payload integration. The platform is powered by Nautomate, BAE Systems' autonomous control system.

A first-of-kind certification process

Lloyd's Register is leading Herne through certification against its Unmanned Marine Systems (UMS) Code, with compliance through classification to the Rules and Regulations for the Construction and Classification of Submersibles and Diving Systems (SDS Rules). These rules provide detailed technical solutions underpinning the performance requirements of the UMS Code, delivering a structured pathway to ensure the safety and reliability of large uncrewed submersibles.

Herne is expected to become the first XLAUV certified to the UMS Code and the first unmanned submersible classed under the SDS Rules, setting a precedent for how future platforms are assessed and approved.

Scott Jamieson, Defence Solutions managing director at BAE Systems, is unequivocal about the significance of the programme. "Assured and trusted autonomy will be central to future naval operations worldwide; our fast-paced development puts us at the forefront of this advancement. Herne will be the world's first XLAUV and unmanned submersible certified under both the UMS Code and SDS Rules, setting a new global benchmark for militarised autonomous undersea operations," he said.

Software assurance at the core

Operating underwater presents unique challenges for navigation and situational awareness. Unlike surface vessels, submerged platforms cannot rely on radar or cameras, and must instead depend on sonar, inertial navigation systems and advanced algorithms to interpret their surroundings and avoid obstacles. Software is key to managing complex, reliable autonomous decisions in environments with limited sensing. Nautomate is progressing through LR's Software Conformity Assessment under the UMS Code.

For BAE Systems, the emphasis has been on embedding assurance into the design process from the outset rather than treating it as a later-stage consideration. Nick Martin, Maritime Autonomy project manager at BAE Systems, said: "We're excited to partner with LR as we progress the certification of the Herne XLAUV. Purpose built with a rigorous focus on safety, assurance and certification readiness, Herne sets a new benchmark for trusted autonomous maritime systems."

Certification has been incorporated into the design and development process from the start, shaping decisions around systems architecture, redundancy and operations. This approach reduces risk during trials, accelerates the path to operational use and provides navies with greater confidence in deploying uncrewed capability at scale.

The regulatory landscape

LR has been at the forefront of autonomous system assurance since 2017, when it became one of the first classification societies to publish a dedicated goal-based standard for uncrewed maritime technologies. The organisation previously applied the UMS Code to BAE Systems' Autonomous Pacific 24, the first naval platform to complete certification under the Code.

Jordan McRuvie, LR's Unmanned Marine Systems specialist, notes that the assurance landscape is particularly challenging for larger vessels and defence platforms that sit outside the scope of existing commercial codes. The forthcoming IMO Maritime Autonomous Surface Ships Code, expected to be issued in 2026, is set to provide a goal-based, non-mandatory foundation for future assurance, but tailoring will still be required to meet the demands of defence applications.