Principal Thermal Engineer

About the Role

Leonardo is seeking an experienced Thermal Engineer to join multidisciplinary project teams, focusing on the development and production of leading-edge Defence products within Land, Naval, Seeker, and Space domains. You will play a key role in advising on thermal performance, ensuring products meet demanding environmental and operational requirements, and supporting both new innovations and proven legacy products.

This role is ideal for a candidate with a strong analytical mindset, a flair for problem-solving, and the ability to manage complex interdependencies across multiple programmes and business units.

What You'll Do:

• Conduct thermal analysis of mechanical designs to assess performance and safety using thermal analysis software, CFD techniques, and classical hand calculations.
• Provide expert guidance on cooling strategies and recommend thermal design improvements.
• Advise on materials and manufacturing techniques with an emphasis on thermal performance and mechanical integrity.
• Define thermal requirements and develop methods for verifying compliance across Leonardo products.
• Drive innovation in thermal design, introducing new technologies and methodologies.
• Support product development through all phases—from design and testing to final certification.
• Deliver thermal solutions that meet performance requirements on time and within budget.
• Contribute to technical documentation, including material for peer reviews and stage/gate approvals.

All members of the Analysis Team are encouraged and supported to continually develop their skills, including (but not limited to) Structural, Thermal, Pressure and Model Driven domains.

What You'll Bring:

• Degree in Mechanical or Aeronautical Engineering.
• Post-graduate experience in Thermal engineering with proven expertise in thermal analysis and developing equipment for challenging environments.
• Proficiency in CFD tools (preferably Ansys Icepak and Ansys Fluent) and classical hand calculation methods.
• Experience of environmental test methods for design verification and working knowledge of design certification for land-based and airborne equipment.
• Knowledge of relevant Regulatory Standards and equipment safety compliance requirements.
• Excellent verbal and written communication skills with the ability to influence.
• A proven problem solver with a practical, pragmatic approach.
• Ability to take ownership of work packages and manage workload.

Desirable:

• Experience in the design, development, and test of electronics packaging and/or aerospace equipment.
• Experience of manufacturing and joining techniques, and engineering material properties.
• Professional recognition as a Chartered Engineer and full membership of a relevant engineering institution.

We encourage you to apply even if you don't meet every requirement; a good attitude and willingness to learn are highly valued.

Working Pattern & Location:

This is a permanent, hybrid role, requiring regular onsite presence (up to 5 days a week, 37 standard hours with potential overtime). Flexible working and hybrid options are available when project work allows. The primary location is Basildon, with options in Bristol or Southampton.

Security Clearance:

This role is subject to pre-employment screening in line with the UK Government’s Baseline Personnel Security Standard (BPSS). Additional Personnel Security Controls (National Security Vetting, ITAR) may apply, potentially including eligibility for Security Check (SC) or Developed Vetting (DV).