Principal Mechanical Engineer — Nuclear & Defence Leader

Mott MacDonald; Tadley; Hybrid; GBP 90,000 - 130,000; Full time

Benefits offered by this job

Private medical insurance

Life assurance (up to 4x salary)

Health cash plan

Flexible benefits

Employee ownership

Generous holiday allowance

Job summary

Mott MacDonald is seeking a Principal Mechanical Engineer to join the Nuclear, Defence and Civil division. You will lead mechanical engineering across a diverse portfolio, from feasibility through detailed design, ensuring safe, compliant solutions for complex projects.

Working with clients and multidisciplinary teams, you’ll deliver high-quality engineering outputs, provide technical leadership, and support development of others while upholding rigorous standards and regulatory requirements.

Qualifications

• Degree in Mechanical Engineering or a relevant engineering discipline
• Chartered status with the IMechE or progress towards chartership
• Strong experience in mechanical engineering design within a highly regulated industry (nuclear/defence or similar)
• Experience taking technical responsibility for delivery, review and assurance of mechanical engineering work
• Broad knowledge of industry standards, legislation and engineering principles
• Experience across feasibility, FEED and detailed design lifecycle stages
• Ability to solve complex engineering problems and make sound technical decisions
• Experience leading multidisciplinary teams
• Strong client-facing and stakeholder management skills
• Commercial awareness and ability to deliver work within programme and budget

Responsibilities

• Take a leading technical role delivering mechanical engineering across projects from feasibility to detailed design
• Work across nuclear decommissioning, defence and nuclear new build
• Develop, review and deliver mechanical designs and technical solutions
• Produce and oversee engineering documentation, calculations, specifications
• Provide technical assurance through reviews and approvals
• Collaborate with clients to understand requirements and propose solutions
• Provide technical direction and resolve complex engineering challenges
• Lead multidisciplinary teams for integrated, fit-for-purpose outcomes
• Ensure safety, quality and regulatory requirements throughout design and delivery
• Present solutions in client and project environments
• Support bids and identify opportunities with clients
• Visit client sites as required to support delivery and relationship building

Skills

Mechanical design

Technical leadership

Client-facing

Stakeholder management

Problem solving

Multidisciplinary teamwork

Regulatory awareness

Education

Degree in Mechanical Engineering

Chartered status or progress towards chartership

Job description

Mott MacDonald is seeking a Principal Mechanical Engineer to join the Nuclear, Defence and Civil division. You will lead mechanical engineering across a diverse portfolio, from feasibility through detailed design, ensuring safe, compliant solutions for complex projects.

Working with clients and multidisciplinary teams, you’ll deliver high-quality engineering outputs, provide technical leadership, and support development of others while upholding rigorous standards and regulatory requirements.