Principal Mechanical Engineer

Amentum; Gloucester; Hybrid; GBP 60,000 - 80,000; Full time

Job summary

A leading engineering firm in Gloucester is seeking a Principal Mechanical Engineer to support nuclear fleet transformations and new reactor developments. You will manage mechanical design solutions and collaborate with various stakeholders. The role offers a competitive salary and comprehensive benefits. Experience in heavy infrastructure and proficiency with CAD software are essential. Flexible working arrangements are available.

Benefits

Free medical cover

Digital GP service

Enhanced parental leave pay

Qualifications

• Chartered status or working towards it (e.g., IMechE, MIET).
• Experience in heavy infrastructure, nuclear, or regulated industry design.
• Ability to produce technical drawings to BS EN 8888 and P&ID standards.

Responsibilities

• Take ownership of technical challenges, develop strategies, and implement solutions with stakeholder engagement.
• Deliver technical analysis and design solutions.
• Collaborate with international SMR developers to pass the ONR’s GDA process.

Skills

Teamwork and multidisciplinary collaboration skills

Experience with American codes

Proficiency with CAD software (AutoCAD, Inventor, Creo, SolidWorks)

Knowledge of safety cases in industrial environments

Education

MEng, MSc, BEng, or BSc in Mechanical Engineering or relevant field

Tools

AutoCAD

SolidWorks

Job description

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Principal Mechanical Engineer, Gloucester

Client: Amentum

Location: Gloucester, United Kingdom

Job Category: Other

EU work permit required: Yes

Job Reference: 6f57c959f34f

Job Views: 28

Posted: 12.08.2025

Expiry Date: 26.09.2025

Job Description:

We’ll inspire and empower you to deliver your best work so you can evolve, grow and succeed - today and into tomorrow. We offer an exciting range of opportunities to develop your career within a supportive and diverse team who always strive to do the right thing for our people, clients and communities.

People are our greatest asset, and we offer a competitive package to retain and attract the best talent. UK employees also receive benefits such as free medical cover, digital GP service, enhanced parental leave pay, free membership of employee assistance programs, professional development reimbursements, and community involvement through our Collectively program.

About the Opportunity

Amentum is recruiting a Principal Mechanical Engineer to join our Energy sector, supporting UK nuclear fleet transformations and new small modular reactor developments. Our work covers Licensing, New Build, Generation, Life Extension, and Decommissioning, with high demand across the nuclear industry.

Your role involves managing and delivering mechanical design solutions on projects of various sizes, collaborating with Operations and Engineering Managers to maximize value. The position is based at one of our Energy offices (Newcastle, Warrington, Glasgow, Gloucester, Stockton, Bristol, or Knutsford), with flexible working options.

Role Responsibilities

• Take ownership of technical challenges, develop strategies, and implement solutions with stakeholder engagement.
• Deliver technical analysis and design solutions.
• Produce and review design documentation, including assumptions, specifications, and calculation notes.
• Collaborate with international SMR developers to pass the ONR’s GDA process.
• Review and justify design decisions to the ONR.
• Fulfill CDM responsibilities.

Minimum Qualifications & Experience

• MEng, MSc, BEng, or BSc in Mechanical Engineering or relevant field.
• Experience in heavy infrastructure, nuclear, or regulated industry design.
• Chartered status or working towards it (e.g., IMechE, MIET).
• Teamwork and multidisciplinary collaboration skills.
• Experience with American codes, designing pumps, valves, heat exchangers, tanks, filters, HVAC equipment, and creating datasheets.
• Proficiency with CAD software (AutoCAD, Inventor, Creo, SolidWorks).
• Ability to produce technical drawings to BS EN 8888 and P&ID standards.
• Knowledge of safety cases in industrial environments.
• Familiarity with Matlab and MathCAD is beneficial.
• Experience in writing test plans for Equipment Qualification.
• Understanding of UK Nuclear Regulatory processes is desirable.

Our Culture

We prioritize safety, integrity, inclusion, and diversity. Supporting our people through a caring culture, we value mental health, belonging, and inclusive practices. We partner with VERCIDA to attract diverse talent and are committed to accessibility and reasonable adjustments in our recruitment process.