Principal Mechanical Engineer

Overview

In this role you will lead Front End Engineering for SMRs, AMRs and Fusion projects within Assystem’s Fusion and Modular Nuclear unit. You’ll spearhead optioneering studies and guide a multi-disciplinary design team to deliver core design documents and system integration. You will chair design reviews, lead HAZID/HAZOP studies, and ensure compliance with HSQ and regulatory standards. This is a hands-on leadership role shaping next-gen nuclear and fusion power systems in a regulated environment.

Pay / Benefits

• Hybrid work: 1-2 days remote per week
• Attractive social benefits
• Engaging Employee Committee and holiday bonuses
• Ongoing training and career opportunities
• 70% of managers promoted internally

Responsibilities

• Lead Front End Engineering for SMR/AMR/Fusion projects and coordinate with multi-disciplinary teams
• Direct a design team to produce critical documents (PFDs, Equipment Datasheets, DDDs, Requirements Specifications)
• Drive optioneering to select solutions aligned with client objectives
• Integrate developed systems into broader plant infrastructure for optimum performance
• Act as technical lead for designated scopes and ensure high-quality technical oversight
• Chair Design Reviews and lead HAZID/HAZOP studies with diverse teams
• Ensure compliance with company H&S policies and project/Quality Management System standards

Key requirements

• Experience in highly regulated sectors (nuclear, thermal power, or oil & gas)
• Strong understanding of thermal power systems and nuclear plant operations
• Proficiency in optioneering and option evaluation with ALARP and BAT arguments
• Leadership experience mentoring junior staff and managing small teams
• Excellent communication with internal and external stakeholders
• Familiarity with ASME, European, and UK codes and standards; knowledge of Product Safety Legislation
• Requirements management and systems engineering principles
• Results-oriented with ability to work independently and in teams
• British National with eligibility for UK security clearance

• leadership
• mentoring
• stakeholder management
• periodic optioneering and option studies
• ALARP and BAT argumentation
• HAZID/HAZOP leadership

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