At a Glance
- Tasks: Lead innovative mechanical engineering projects that shape national security and infrastructure.
- Company: Join Babcock, a leader in defence and engineering with a commitment to safety.
- Benefits: Enjoy generous holidays, pension schemes, health support, and flexible working options.
- Other info: Hybrid working available; be part of an inclusive culture that values diversity.
- Why this job: Make a real impact on national defence while advancing your engineering career.
- Qualifications: Level 6 qualification in Mechanical Engineering or equivalent experience required.
The predicted salary is between 57300 - 71600 £ per year.
Location: City, County + Hybrid Working Arrangements
Compensation: £57,300 - £71,600 Depending on experience + Benefits
Role Type: Full time / Permanent
Engineer the Future of Naval Infrastructure and National Security
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 provide expert technical leadership across the full engineering lifecycle, from concept and design development through to implementation, operation, decommissioning and disposal. You’ll help ensure compliance with regulatory requirements, engineering standards and safety obligations while delivering high‑quality solutions that make a real difference to national defence and critical infrastructure.
Day‑to‑day, you’ll be required to:
- Lead and support mechanical engineering design activities throughout the full project lifecycle.
- Specify technical requirements, produce engineering guidance and support tender and commercial activities.
- Provide technical oversight of mechanical services designs, ensuring compliance with regulatory and industry standards.
- Conduct design reviews, validation activities, technical audits, site inspections and stakeholder meetings.
- Mentor junior engineers while providing expert advice to stakeholders across the business.
This role is full time, 35 hours per week and is predominantly office‑based but will require site visits across Devonport. Hybrid working arrangements are available, with a minimum of two days per week on site and additional presence as required to support business needs.
Essential experience of the Principal Mechanical Engineer
- Extensive knowledge of mechanical engineering systems including steam and condensate, industrial gases, fresh water, demineralised water and domestic water services.
- Experience applying the full engineering design lifecycle across complex projects.
- Strong understanding of relevant regulations, legislation, codes and standards governing mechanical systems design.
- Experience working within nuclear, defence or other highly regulated, high‑hazard industries.
- Experience supporting commissioning, performance evaluation and engagement with clients and key stakeholders.
Qualifications for the Principal Mechanical Engineer
- Level 6 qualification in Mechanical Engineering or a closely related discipline, or a Level 5 qualification with substantial relevant experience.
- Chartered Engineer status or actively working towards Chartered Engineer accreditation.
Security Clearance
The successful candidate must be a sole UK national who is 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.
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.
- ‘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
Disability confidence statement
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: 20/07/2026
StudySmarter Expert Advice🤫
We think this is how you could land Principal Mechanical Engineer in Plymouth
✨Get Your Hands Dirty at Engineering Events
Join local engineering meetups or industry conferences related to mechanical engineering. Whether it's a workshop or a career fair, these events are goldmines for networking and getting a foot in the door. Plus, you can showcase your passion and enthusiasm directly to potential employers like Nuclearinst.
✨Connect with Professors & Peers
Tap into your university’s resources—professors often have connections in the industry. Don’t be shy to ask about potential openings or recommendations. Your classmates might also know of companies hiring. Often, it’s who you know that gets you in front of the right people!
✨Highlight Your Projects and Practical Experience
When you land those interviews, make sure to talk about your hands-on projects or internships. Whether it's a design project or hands-on experience with CAD software, specific examples will make you stand out. Companies like Nuclearinst love to hear about practical applications of your skills.
✨Apply Directly on Company Websites
Check out the careers page of Nuclearinst and apply directly through there. It shows initiative and interest in their specific values. Plus, you'll often find openings that aren't advertised on job boards, giving you a better chance to land that full-time gig!
We think you need these skills to ace Principal Mechanical Engineer in Plymouth
Some tips for your application 🫡
Show Off Your Technical Expertise:In mechanical engineering, it’s vital to highlight your technical skills and projects. Make sure to include relevant software proficiency (like CAD tools) in your CV. If you've worked on specific engineering projects, detail your key contributions — we want to see how you’ve applied your skills in a practical setting!
Focus on Problem-Solving Examples:Employers in mechanical engineering love to see how you handle challenges. Use your cover letter to share specific instances where you’ve solved a complex problem or improved a design. This will show us you're not just knowledgeable but also capable of applying that knowledge effectively.
Highlight Relevant Certifications:Include any relevant certifications or training that can set you apart from the competition. Whether it's coursework from your degree, a recognised certification, or extra training in new technologies, we love to see candidates who continuously improve their skill set. This tells us you're serious about your career in engineering!
Tailor Your CV for the Role:Don’t forget to customise your CV for Nuclearinst and the Principal Mechanical Engineer role specifically. Pull examples from your experience that align with the job description — it shows us you've done your research and are genuinely interested in becoming part of the team. We recommend applying through our website to ensure your application gets to the right people!
How to prepare for a job interview at Nuclearinst
✨Brush Up on Your CAD Skills
Since mechanical engineering often involves design processes, be ready to showcase your proficiency in CAD software like SolidWorks or AutoCAD. Bring along a digital portfolio or even some sketches that demonstrate your design capabilities — it’s a great way to show what you can bring to the table at Nuclearinst.
✨Prepare for Technical Questions
Expect technical questions that test your understanding of engineering principles and problem-solving skills. You might get hypothetical scenarios where you need to design a component or troubleshoot a mechanical system. Practising these types of questions will give you the confidence to tackle whatever comes your way!
✨Show Your Team Spirit
As a full-time mechanical engineer, collaboration is key! Be ready to share examples of past team projects or any experiences where you contributed to solving a complex problem with others. Demonstrating your ability to work in a team will resonate well with the interviewers at Nuclearinst.
✨Discuss Your Future Goals
Since this is a full-time position, your long-term vision is important. Be open about your career aspirations, whether it’s mastering a specific tool or leading projects. This shows that you're committed not just to learning but also to growing with Nuclearinst, making you a more appealing candidate.
