Job Title: Principal Mechanical Engineer
Location: Plymouth, Devon
Compensation: £57,300 - £71,600 Depending on Experience + Benefits
Role Type: Full time / Permanent
Role ID: SF72890
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 Engineer at our Devonport Royal Dockyard site.
The role
As a Principal Mechanical Engineer, you’ll play a vital role in delivering major infrastructure projects that support the UK’s submarine sustainment programmes. Working within our Major Infrastructure Projects directorate, you'll provide technical leadership across complex mechanical engineering systems that are essential to maintaining safe, effective, and world-class defence facilities.
Day-to-day, you’ll have an opportunity to apply your expertise to nationally significant projects while developing your career within one of the UK's leading engineering and defence organisations. You'll collaborate with multidisciplinary teams, influence major engineering decisions, and help ensure that critical facilities are designed, constructed, and accepted into service safely and effectively. Your work will directly contribute to the operational readiness of vital defence capabilities while advancing innovation, engineering excellence, and safety performance.
- Reviewing mechanical engineering designs to ensure compliance with engineering standards and Design Authority requirements.
- Providing subject matter expertise and technical guidance to support engineering problem solving and project delivery.
- Assessing the integration of mechanical systems with wider multidisciplinary infrastructure designs.
- Ensuring safety case requirements are supported and substantiated through robust engineering solutions.
- Supporting quality, configuration control, testing, and acceptance activities to deliver safe and effective facilities.
This role is full time, 35 hours per week and is based on site at Devonport Royal Dockyard.
Essential experience of the Principal Mechanical Engineer
- Extensive experience in Mechanical Engineering, ideally within marine, defence, infrastructure, or similarly regulated environments.
- Strong experience substantiating high-integrity engineering systems.
- Proven experience managing engineering change within a nuclear regulated environment.
- Experience reviewing, assuring, and approving complex engineering design packages.
- Strong stakeholder engagement and technical leadership capabilities within multidisciplinary project teams.
Qualifications for the Principal Mechanical Engineer
Essential
- Bachelor's Degree in Mechanical Engineering.
Preferred
- Chartered Engineer registration with the Engineering Council.
- Nuclear Introductory Course qualification or equivalent nuclear industry knowledge.
Security Clearance
The successful candidate must be able to achieve and maintain Security Check (SC) 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 (www.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 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. This Window opens February through to March annually.
- ‘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
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 are a disability confident committed employer. If you have a disability or need any reasonable adjustments during the application and selection stages, please email careers@babcockinternational.com 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: 10/09/2026
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