Principal Commissioning Engineer - Mechanical

Job Title: Principal Mechanical Commissioning Engineer

Location: Plymouth, Devon

Compensation: £57,300 - £71,600 Depending on Experience + Benefits

Role Type: Full time / Permanent

Role ID: SF71776

At Babcock we're working to create a safe and secure world, together, and if you join us, you can play your part as a Principal Mechanical Commissioning Engineer at our Devonport Royal Dockyard site.

The role

As a Principal Mechanical Commissioning Engineer, you'll be a subject matter expert supporting the commissioning of strategic weapons systems on Vanguard Class submarines within the SSBN Commissioning Group. This is an opportunity to take a leading role in one of the UK's most important defence programmes, combining technical expertise, leadership and operational excellence to ensure the safe delivery of critical submarine systems.

Day-to-day, you'll work closely with engineering, operations, safety, quality and project teams, helping to develop capability within the organisation while supporting the delivery of complex commissioning activities in a highly regulated environment. This role offers excellent opportunities for professional growth, leadership development and the chance to make a meaningful contribution to national security.

• Leading the planning and delivery of commissioning, testing and setting-to-work activities for nuclear submarine mechanical systems.
• Preparing and ensuring the authorisation of test documentation to support project delivery programmes.
• Promoting a strong safety culture and ensuring compliance with safe systems of work and regulatory requirements.
• Managing and developing mechanical commissioning teams, supporting capability growth and resource planning.
• Collaborating with key stakeholders to resolve complex technical challenges and deliver successful commissioning outcomes.

This role is full time, 35 hours per week and is based on site at Devonport Royal Dockyard.

Essential Experience Of The Principal Mechanical Commissioning Engineer

• Significant experience commissioning, operating and maintaining mechanical systems within high-hazard or heavily regulated industries.
• Strong knowledge of control of work processes, safe release of systems and safe systems of work.
• Understanding of relevant licence conditions, operating rules and commissioning requirements.
• Experience managing multiple complex commissioning packages within demanding operational environments.
• Strong leadership, planning, organisational and stakeholder management skills.

Qualifications For The Principal Mechanical Commissioning Engineer

• Level 4 qualification in a relevant Engineering discipline, or
• Level 3 qualification in a relevant Engineering discipline with significant commissioning operations experience.

Security Clearance

The successful candidate must be a sole UK National who is able to achieve and Naval Nuclear Propulsion Information (NNPPI) security clearance for this role.

Many of the positions within our company are subject to national security clearance and Trade Control restrictions. This means that your eligibility for certain roles may be affected by your place of birth, nationality, current or former citizenship, and any residency you hold or have held. Further details are available at United Kingdom Security Vetting: clearance levels - GOV.UK (

What We Offer

• Generous holiday allowance
• Matched contribution pension scheme, with life assurance
• Access to a Digital GP, annual health check, and nutritional consultations through Aviva DigiCare+
• Employee share scheme
• Employee shopping savings portal
• Payment of Professional Fees
• Reservists in the armed forces receive 10-days special paid leave
• Holiday Trading is a benefit that allows UK Babcock employees to buy additional leave or to sell up to one working week of annual leave from their annual entitlement. There is an annual Window to request this benefit. 'Be Kind Day' enables employees to take one working day's paid leave a year (or equivalent hours) to undertake volunteering work with their chosen organisation or registered charity
• Excellent development opportunities and benefits package including an employee assistance programme supporting physical, mental and financial wellbeing.

Babcock

We're Babcock — a global FTSE 100 organisation with over 26,000 people working together to make a difference.

Here, you'll be part of something bigger. From initial design to final decommissioning, your work will contribute to products and services that are essential to national security and public infrastructure. Together, we're building a future that lasts — not just through the impact we make, but through meaningful careers that respect your work-life balance.

We call that lifetime engineering.

Join us and see how far we can go, together.

We're a disability confident committed employer. If you have a disability or need any reasonable adjustments during the application and selection stages, please email with the subject header 'Reasonable adjustments requirement'. We're committed to building an inclusive culture where everyone's free to thrive. We are happy to talk about flexible working – please ask about alternative patterns of work at interview.

Closing Date: 31/08/2026

#BABDESTNUC

#J-18808-Ljbffr