Principal Commissioning Engineer - Mechanical

Job Title: Principal Mechanical Commissioning Engineer

Location: Plymouth, Devon

Compensation: £57,300 + Benefits

Role Type: Full time / Permanent

Role : SF71776

As a Principal Mechanical Commissioning Engineer, you’ll play a pivotal leadership role in delivering commissioning activities across complex mechanical systems within a highly regulated defence environment. You will lead from the front, ensuring critical infrastructure and assets are brought into service safely, efficiently, and to the highest quality standards. Day-to-day you will influence project outcomes, mentor engineering teams, and act as a technical authority, helping to deliver essential capabilities that support national defence and security.

This role offers the chance to deepen your expertise, expand your leadership impact, and build a meaningful career within defence, aerospace and engineering. The role is full time, 35 hours per week and is based at the Devonport Royal Dockyard site.

• Lead mechanical commissioning activities across complex projects and systems.
• Ensure systems are commissioned safely, meeting all regulatory and quality requirements.
• Provide technical leadership and guidance to engineering and commissioning teams.
• Develop and review commissioning documentation, procedures, and test plans.
• Coordinate with stakeholders to ensure seamless project delivery.

• Significant experience in mechanical commissioning within engineering or defence environments.
• Strong technical knowledge of mechanical systems and commissioning processes.
• Experience leading teams and influencing stakeholders in complex, safety‑critical settings.
• Experience working within highly regulated industries with a strong focus on safety and compliance.
• Ability to solve complex engineering challenges with a structured and analytical approach.

• Degree in Mechanical Engineering or equivalent experience.
• Chartered Engineer status or working towards it – Preferred.
• Relevant professional accreditation or membership – Desirable.

The successful candidate must be a UK National able to achieve and maintain Naval Nuclear Propulsion Information (NNPPI) security clearance for this role. Eligibility may be affected by nationality, citizenship, and residency. For more details, see United Kingdom Security Vetting: clearance levels –

• Generous holiday allowance.
• Matched contribution pension scheme with life assurance.
• Access to a Digital GP, annual health check, and nutritional consultations through Aviva Digi Care+.
• Employee share scheme.
• Employee shopping savings portal.
• Payment of professional fees.
• Reservists receive 10 days special paid leave.
• Holiday trading benefit – purchase or sell up to one working week of annual leave.
• Be Kind Day – one working day's paid leave per year for volunteering.
• Excellent development opportunities and benefits package, including an employee assistance programme supporting wellbeing.

Closing date: 25/06/2026