Principal Thermal Engineer

Overview

Leonardo is seeking an experienced Thermal Engineer to play a key role in the development and production of leading‑edge Defence products within Land, Naval, Seeker and Space domains supporting both new innovations and proven legacy products. The successful candidate will conduct thermal analysis, communicate results, and advise on all aspects of Thermal Engineering activities, working with multi‑discipline project teams and customers across the UK.

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 as required. 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.

• Degree in Mechanical or Aeronautical Engineering with post‑graduate experience in Thermal engineering.
• Proven expertise in thermal analysis, with a track record of developing equipment for challenging and extreme operating environments.
• Proficiency in CFD tools, preferably Ansys Icepak and Ansys Fluent, alongside a solid foundation in 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 Regulatory Standards including Def Stan 00‑970, Health and Safety HSE Regulations, Pressure Equipment Regulation, Pressure System Safety Regulation and Fluorinated Gas Regulations.
• Awareness of equipment safety compliance requirements, including the ability to support inspection processes and generate fault and failure reports.
• Excellent verbal and written communication skills with the ability to influence the direction of both internal and external customers.
• A proven problem solver with a practical, pragmatic approach.
• Ability to take ownership of work packages, planning and scheduling own workload and the work of others.

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

The most important skill is a good attitude and willingness to learn.

Onsite regularly, up to 5 days a week (37‑hour standard work week, overtime if approved by project and employee) to deliver security classification and role‑specific tasks for projects. The company allows hybrid working, so working from home is possible when project work allows. Basildon is the primary location option but Southampton or Bristol is possible.

This role is subject to pre‑employment screening in line with the UK Government’s Baseline Personnel Security Standard (BPSS). An additional range of Personnel Security Controls referred to as National Security Vetting (NSV) and ITAR may apply, which could include meeting the eligibility requirements for The Security Check (SC) or Developed Vetting (DV). Please visit  for more information and guidance.

GB - Basildon
GB - Bristol - Coldharbour Lane
GB - Southampton

Permanent

Leonardo is a global leader in Aerospace, Defence, and Security. The company is committed to building an inclusive, accessible, and welcoming workplace. If you have any accessibility requirements to support you during the recruitment process, just let us know.