Principal Mechanical Engineer

Job title: Principal Mechanical Engineer
Location: Portsmouth Naval Base – hybrid and flexible working arrangements available. Salary: Up to £60,000 (dependent on skills and experience).

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• Lead and conduct early lifecycle engineering activities, including technical investigations, root cause analysis and feasibility studies.
  
• Apply engineering theory/technical knowledge to support findings and recommendations.
  
• Define equipment/system technical requirements and acceptance routes.
  
• Apply and manage requirements to drive the development of design solutions for marine mechanical equipment and systems.
  
• Undertake design substantiation via calculation for marine mechanical systems and equipment, including mechanical simulation/analysis in structures, fluids and heat transfer, with appropriate optimisation and verification/validation routines.
  
• Manage technical risk, safety, requirements compliance and design maturity to align with design review gate requirements.
  
• Present to engineering design review panels and produce design/analysis/technical reports, system/equipment specifications, scopes of work and assess supplier responses.
  
• Liaise with MOD establishments, test facilities, sub-contractors, suppliers and customers to satisfy project needs.
  

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• Qualified to degree level, or equivalent, in mechanical engineering or a related STEM subject.
  
• Ideally professionally registered (CEng) through a relevant professional engineering institution (e.g., IET, IMechE, IMarEST) or have a defined plan to attain registration.
  
• Proactive continuation of professional development.
  
• Experience applying marine/mechanical engineering in complex industrial/military applications.
  
• Competent in assessing mechanical solutions from first principles using recognised toolsets.
  
• Aware of project management principles with consideration of time, scheduling, cost and quality factors.
  
• Awareness of Systems Engineering and its benefits to complex engineering projects.
  
• Experience applying defence and marine standards, including DefStan, classification society rules, ISO and relevant regulatory frameworks (MCA, IMO).
  

In addition to a competitive pension scheme, BAE Systems offers share plans and a wide 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 Warship Technical Authority (WTA) – Principal Mechanical Engineer will deliver professional engineering services to Warship Support in Naval Marine Mechanical Equipment and Systems. The role requires leading others in activities across the engineering lifecycle to support in-service Naval Marine Platforms and to provide mechanical engineering capability across a broad set of challenges to meet the needs of specific Naval platforms, the WTA team and the customer programme.

This is a place where you’ll be able to make a real difference. You’ll be part of an inclusive culture that values thought, rewards integrity and merit, and where you’ll be empowered to fulfil your potential. We welcome people from all backgrounds and want to ensure our recruitment processes are as inclusive as possible.

If you have a condition that may affect performance in certain assessments, please speak to your recruiter about reasonable adjustments. Some roles are subject to security and export control restrictions. Applicants must, as a minimum, meet Baseline Personnel Security Standard; higher levels of Security Vetting may apply. The closing date is 11 September 2025. We reserve the right to close this vacancy early if we receive sufficient applications. Please submit your application early. LI-TP1 LI-Hybrid