Job Title: Principal Mechanical Engineer
Location: Hessle or Grimsby + Hybrid Working Arrangement
Compensation: Competitive Salary + Benefits
Role Type: Full time / Permanent
Role ID: SF75614
Lead the delivery of complex engineering solutions that support the UK's future
At Cavendish Nuclear, we’re working to create a safe and secure world, together. If you join us, you can play your part as a Principal Mechanical Engineer at our Hessle or Grimsby sites.
Cavendish Nuclear is expanding in the Humber region and now recruiting within our new office in Grimsby, as well as current office in Hessle. This is a unique opportunity to join a growing business and help deliver some of the UK's most complex and safety-critical programmes across clean energy, nuclear decommissioning and defence.
The role
As a Principal Mechanical Engineer, you'll provide technical leadership across major engineering programmes, shaping engineering strategy and ensuring the delivery of innovative, safe and commercially successful solutions. You'll influence project outcomes, support customer success and play a key role in developing engineering capability across the business.
Working with multidisciplinary teams, suppliers and key stakeholders, you'll be responsible for driving technical excellence while ensuring projects are delivered to the highest standards of safety, quality and performance. This is an opportunity to make a lasting impact on nationally significant programmes while advancing your career within a leading engineering organisation.
Day-to-day, you will be:
- Leading the development of mechanical engineering solutions for complex and high-profile projects.
- Managing project scope, priorities and delivery plans to meet customer requirements.
- Collaborating with multidisciplinary teams, suppliers and stakeholders to resolve technical challenges.
- Ensuring all engineering work complies with safety, quality and regulatory standards.
- Providing technical leadership, guidance and assurance to support successful project delivery and team development.
This is a full-time, permanent opportunity working 37 hours per week, with hybrid working arrangements available and an expectation to be onsite three days per week at our Hessle or Grimsby office.
Essential experience of the Principal Mechanical Engineer:
- Proven experience leading mechanical engineering activities on complex projects.
- Experience coordinating multidisciplinary teams and managing engineering interfaces.
- Strong understanding of the full engineering lifecycle, from concept and design through to commissioning.
- Experience working in highly regulated or safety-critical environments.
- Knowledge of mechanical design, risk assessment methodologies and technical leadership.
Qualifications for the Principal Mechanical Engineer:
Degree in Mechanical Engineering or a related engineering discipline.
Security Clearance
The successful candidate must be able to achieve and maintain Standard (BPSS) security clearance for this role. 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 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 Cavendish 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
- Excellent development opportunities and benefits package including an employee assistance programme supporting physical, mental and financial wellbeing.
Cavendish
We’re Cavendish Nuclear — a team of c5,000 specialists and a core part of Babcock International Group.
Here, you’ll be part of something bigger. Across clean energy, defence, and civil decommissioning, your work will contribute to projects that are critical to energy security and national protection. Together, we’re shaping a future that lasts — not only through the impact we make, but through meaningful careers that respect your work-life balance.
Join us and discover 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: 09/09/2026
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