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