Principal Thermal Mechanical Engineer

Our client, a leading organisation in the defence and security sector, is seeking a Principal Thermal Mechanical Engineer for a contract opportunity in Cowes. The role will focus on thermal engineering and mechanical…

Pay rate £51.86 – £70/hour
Contract type Contract
Posted 5 October 2026

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About this contract

Our client, a leading organisation in the defence and security sector, is seeking a Principal Thermal Mechanical Engineer for a contract opportunity in Cowes. The role will focus on thermal engineering and mechanical design activities within complex, highly regulated projects. It offers hybrid working, with two to three days per week required on site.

Key Responsibilities:

Leading thermal mechanical engineering activities throughout the project lifecycle
Developing and reviewing thermal management solutions for complex defence systems
Carrying out thermal analysis, calculations and system assessments
Producing and reviewing engineering specifications, technical reports and design documentation
Providing technical guidance and mentoring to engineering teams
Supporting design reviews, testing, validation and troubleshooting activities
Collaborating with multidisciplinary teams, suppliers and project stakeholders
Ensuring engineering outputs comply with relevant standards, quality requirements and security restrictions

Job Requirements:

Significant experience in thermal mechanical engineering, thermal management or a closely related discipline
Strong understanding of thermal analysis, heat transfer and mechanical design principles
Experience contributing to complex engineering programmes, preferably within defence, aerospace or a highly regulated industry
Ability to interpret technical requirements and develop practical engineering solutions
Strong technical documentation, communication and stakeholder management skills
Ability to work effectively in a multidisciplinary engineering environment
Relevant engineering degree or equivalent professional experience
Ability to satisfy BPSS and progress towards or hold Security Check clearance, subject to ITAR and UK Eyes Only restrictions

Working Arrangements:

Contract position based in Cowes
Hybrid working, with two to three days per week on site
Work within a technically advanced defence and security environment
If you are an experienced Principal Thermal Mechanical Engineer seeking a challenging contract opportunity within the defence sector, apply now to be considered

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