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Thales

Principal Mechanical Engineer

Belfast

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hirly's read of this role

Seniority
Lead / management
Country
GB
Work mode
On-site / unstated
First seen by hirly
13 Oct 2026

Derived automatically from the posting. Upload your resume above to see how the role scores against it.

the posting

Location: Belfast, United Kingdom

Thales is a global technology leader with more than 83,000 employees on five continents. With over 7,500 people in the UK, operating across defence, space, aerospace, and digital security, we help build a future we can all trust. Thales supports the security and stability of our nation by providing extraordinary technology to our customers, as well as delivering social value to the UK with our products and services.

  • Principal Mechanical Engineer
  • Location: based in Belfast, minimum 3 days/ week in office (hybrid), with Other: permanent, full-time

Join Thales as a Principal Mechanical Engineer and take the lead in delivering cutting-edge defence technologies, combining technical excellence, leadership and innovation to help protect and defend what matters most.

What the role has to offer

Shape the Future of Defence Engineering - work on complex Weapon Systems, Missile Systems and Platform products, applying engineering first principles to develop innovative solutions that directly contribute to national and international security

Lead, Influence and Mentor - play a pivotal leadership role within a large Mechanical Design team, driving engineering best practice, influencing technical direction and developing the next generation of engineering talent

Thrive in a Growing Business with Outstanding Flexibility - join a business experiencing significant growth, with hybrid working, a half-day finish every Friday, performance bonus and a comprehensive benefits package that supports both your career and wellbeing

Our Opportunity

We are looking for a Principal Mechanical Engineer to lead the development of advanced defence technologies across our Integrated Airspace Systems portfolio.

Working within a multidisciplinary engineering environment, you'll deliver innovative mechanical solutions for Weapon Systems, Missile Systems and Platform products, applying engineering expertise to solve complex technical challenges and drive successful programme outcomes. As a senior technical leader, you'll champion engineering best practice, influence key design decisions and mentor engineers across the team, helping to build capability as our business continues to grow.

The ideal candidate will bring extensive mechanical design and hardware development experience, strong technical credibility and a proven ability to deliver robust, cost-effective solutions while leading and inspiring others.

Building a Future, we can all trust.

Integrated Airspace Protection Systems (IAS) - our main purpose is to protect and defend. We provide rapid integrated solutions for detection, coordination, fire control, engagement and support. We cover three sectors: Surface Attack & Air Defence (UK), Air Defence (International) and Air Operations & Services as well as Space.

What we offer you

We offer a competitive salary and benefits package designed to support our employees’ wellbeing and professional growth, which includes:

Performance-related bonus

Half day every Friday, usually finishing around 13:00

28 days annual leave (plus bank holidays) with opportunity to buy up to 40 hours/year (pro rata)

24 hours volunteering paid for

Private healthcare

Pension scheme

Life cover

24/7 Employee Assistance Program and access to mental wellbeing app

Employee discount shopping schemes on major brands and retailers

Gym membership discounts

Key Responsibilities and Tasks

Lead Mechanical Design & Development - Deliver detailed mechanical designs and engineering solutions for new and existing products, applying engineering first principles and utilising appropriate CAE tools, analyses, simulations, prototypes and testing methods

Drive Technical Excellence & Decision Making - Analyse complex mechanical engineering challenges, evaluate options, and propose justified technical, technological and methodological solutions aligned with approved architectures, performance requirements and customer needs

Manage Product Definition & Documentation - Create and maintain accurate engineering documentation, including technical drawings to BS 8888 standards, product specifications, development plans, data packs and configuration-controlled design records

Support Product Lifecycle & Change Management - Lead engineering change activities, ensuring the integrity of Bills of Materials (BOMs), manufacturing data, product configurations and associated engineering processes throughout the product lifecycle

Collaborate Across Functions to Deliver Manufacturable Solutions - Work closely with engineering, production, procurement and other stakeholders to develop robust, cost-effective and manufacturable design solutions that meet quality, cost and schedule objectives

Plan, Monitor & Improve Engineering Delivery - Organise and oversee mechanical engineering activities, monitoring technical progress, compliance with target costs and lead times, and driving continuous improvement in engineering quality, performance and delivery

Provide Technical Leadership & Mentoring - Mentor, guide and support engineers within the team, promoting best practice, sharing knowledge, and fostering a culture of technical excellence and professional development

About You

At Thales, we are committed to equal opportunities and welcome all talented individuals to consider joining our team. So even if you don't match every statement below but feel you have some of the experience, knowledge or skills needed for this role, we encourage you to apply. It will take all of us working together to deliver solutions to the world’s most critical challenges.

Acquired a degree (or equivalent qualification) in an engineering discipline, preferably Mechanical Engineering

Proven proficiency in 3D CAD design, particularly Creo and/or CATIA, with extensive experience producing detailed mechanical designs and engineering drawings to BS 8888 standards, including the application of GD&T principles

Demonstrated experience using PLM systems (such as Windchill), managing product structures, Bills of Materials (BOMs) and engineering change processes whilst maintaining configuration and process integrity

Proven ability to apply Design for Manufacture (DfM), DFX methodologies and continuous improvement principles to develop cost-effective, robust and manufacturable design solutions

Demonstrated experience applying international and industry standards, with knowledge of Defence Standards and environmental testing methodologies to support product verification and validation activities

Proven capability in solving complex engineering problems, making sound technical decisions and utilising analysis, simulation and CAE tools (e.g. Ansys, Creo Simulate, SolidWorks Simulate) to support design development

Demonstrated success working within multidisciplinary project and product teams, managing multiple priorities and delivering engineering outputs against programme milestones, cost targets and schedules

Proven ability to lead projects, teams and technical activities, including planning, monitoring and reporting progress to ensure successful delivery of engineering objectives

Demonstrated strong communication, stakeholder management and collaboration skills, with experience working effectively with customers, suppliers and cross-functional teams

Proven commitment to developing others through mentoring, coaching and technical leadership, fostering capability growth and engineering best practice across the team

If you're an experienced Mechanical Engineering leader ready to make an impact on some of the world's most advanced defence programmes, we'd love to hear from you. Apply today and help us build a future we can all trust!

Security Clearance Requirement:

Due to the nature of the work that we do at Thales, many of our roles are subject to security restrictions. This role requires Security Clearance (SC). It would be advantageous if currently held, howe

Original posting on Thales's site ↗

Listed on hirly, a job board. hirly is not the employer: Thales is hiring for this role.

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