Senior Principal Mechanical Engineer: Fusion Systems Leader

Assystem

East Midlands

Hybrid

GBP 90,000 - 130,000

Full time

2 days ago

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Benefits offered by this job

Hybrid work 1–2 days remote per week

Holiday bonuses

Training and career opportunities

Internal promotion opportunities

Job summary

Assystem is seeking a Senior Principal Mechanical Engineer to join the Fusion and Modular Nuclear (FMN) division in the UK. You will lead mechanical design activities for cooling water systems and safety-critical interfaces across multi-project programmes, ensuring compliance with ONR/HSE/regulatory requirements.

The role offers hybrid working 1–2 days remote per week, opportunities to shape advanced nuclear technologies, and exposure to international clients.

Qualifications

Experience leading multi-disciplinary engineering teams on complex reactor-related projects.
Proven ability to perform DFMEA/HAZID analyses for safety-critical systems.
Strong background in cooling water equipment design and interfaces.
Sound knowledge of ONR, Environment Agency, and HSE regulations.
Chartered Engineer (CEng) or equivalent professional accreditation.
Eligibility for UK security clearance (SC) or higher.

Responsibilities

Lead and support the development of designs for cooling water systems and related components.
Conduct DFMEA to identify and mitigate failure modes early.
Perform HAZID to assess and document risks.
Maintain risk register and manage project risks.
Produce design packages aligned with specifications and standards.
Coordinate interfaces between engineering teams, suppliers, and stakeholders.
Prepare technical specifications for procurement, fabrication, and installation.
Collaborate with cross-functional teams across engineering and project functions.