Job Title: Principal Engineer - Mechanical Engineering Location: Barrow-in-Furness. We offer a range of hybrid and flexible working arrangements - please speak to your recruiter about the options for this particular role. Salary: Circa £55,000 depending on skills and experience What you’ll be doing: Leading the design of a mechanical system(s), sub-systems and equipment for the next generation Royal Navy submarines Undertaking functional design activities, calculations and analysis Producing design documentation, Verification & Validation evidence and safety justifications Specifying major equipment and support to procurement, qualification and acceptance activities, working collaboratively with suppliers Providing specialist knowledge and subject matter expertise support the installation, integration and commissioning activities associated with the system and equipment Engaging with stakeholders across the cross-functional project team Mentoring junior engineers in the team Your skills and experiences: Essential: Degree qualified in Mechanical Engineering or relevant subject, or equivalent experience Proven experience in designing mechanical systems and specifying complex, high value mechanical equipment Excellent communication skills and significant experience of dealing with internal and external stakeholders at all levels Knowledge of the complete engineering lifecycle with experience of operating in a number of the key lifecycle phases including requirements, system design, integration and acceptance Good awareness of product safety and SHE Desirable: Knowledge of platform-level constraints such as noise, shock, or survivability Previous experience of integrating mechanical systems and equipment within naval vessels Experience in the design of equivalent systems (hydraulics, Diesel Generators, Cooling, Atmosphere Control (HVAC/Air Puri), Survival, Compressed Air & Gas, Buoyancy, Domestic Systems) – ideally in complex, safety-critical environments (e.g. maritime, aerospace, defence, nuclear, oil & gas and sub-sea) Familiarity with design standards such as ASME, BS EN and other applicable standards Engineering Chartership held or working towards Benefits: As well as a competitive pension scheme, BAE Systems also offers employee share plans, an extensive range of flexible discounted health, wellbeing and lifestyle benefits, including a green car scheme, private health plans and shopping discounts - you may also be eligible for an annual incentive. The Dreadnought Platform Mechanical Engineering Team: This is an exciting time to join a dynamic engineering team on the largest and most complex UK defence programme, which is currently transitioning from system design to build and commissioning support, where your expertise will help drive the delivery of critical mechanical systems into Test & Commissioning. Through close collaboration with our suppliers and key stakeholders, you will be leading the development of design documents to achieve design completion, reviewing supplier documentation, demonstrating compliance with technical requirements and undertaking assessment of design compliance to support the development of our systems. This includes system-level design, technical responsibility, supplier engagement, and the opportunity to support build, test and commissioning activities across a major submarine programme. We offer relocation support packages across all Submarine roles, subject to meeting eligibility criteria. Why BAE Systems? This is a place where you’ll be able to make a real difference. You’ll be part of an inclusive culture that values diversity of thought, rewards integrity, and merit, and where you’ll be empowered to fulfil your potential. We welcome people from all backgrounds and want to make sure that our recruitment processes are as inclusive as possible. If you have a disability or health condition (for example dyslexia, autism, an anxiety disorder etc .) that may affect your performance in certain assessment types, please speak to your recruiter about potential reasonable adjustments. Please be aware that many roles at BAE Systems are subject to both security and export control restrictions. These restrictions mean that factors such as your nationality, any nationalities you may have previously held, and your place of birth can restrict the roles you are eligible to perform within the organisation. All applicants must as a minimum achieve Baseline Personnel Security Standard. Many roles also require higher levels of National Security Vetting where applicants must typically have 5 to 10 years of continuous residency in the UK depending on the vetting level required for the role, to allow for meaningful security vetting checks. Closing Date\: 18th March 2026 We reserve the right to close this vacancy early if we receive sufficient applications for the role. Therefore, if you are interested, please submit your application as early as possible. LI-AG1 LI-Hybrid