Thermal Systems Integration Engineer in Southampton

Prismatic is a technology development company, specialising in the design, manufacture and delivery of innovative, high value aerospace products and systems. Prismatic is a subsidiary of BAE systems, led by a technically and commercially focused team based in Alton, Hampshire. Our cutting-edge systems (such as the high-altitude PHASA-35) have clear commercial value, are developed at pace and address critical customer needs.

As Thermal Systems Integration Engineer, you will be responsible for guiding the design, analysis, integration, and verification of thermal control and management systems for flight platforms. You will lead thermal engineering efforts across the vehicle to ensure all subsystems operate within temperature limits, contribute to multidisciplinary system design, and support test and flight readiness activities.

Tasks and Accountabilities

• Thermal System Design & Analysis
  • Lead the architecture and detailed design of thermal control systems to manage heat loads from electronics, power systems, propulsion, and environmental conditions.
  • Perform and oversee thermal analysis (steady‑state, transient, orbital/altitude environment) using both analytical and simulation tools.
  • Define thermal requirements and translate them into subsystem and component specifications.
• Integration & Cross‑Functional Collaboration
  • Coordinate closely with structures, propulsion, power, avionics, and systems engineering teams to ensure thermal considerations are integrated early and effectively.
  • Identify and manage thermal interfaces between subsystems and negotiate solutions that meet vehicle performance and safety objectives.
• Verification & Testing
  • Lead the development of test plans, thermal test campaigns, and validation efforts from component level through to system and environmental tests.
  • Analyse test data, drive corrective actions, and update thermal models based on empirical results.
• Leadership & Mentoring
  • Provide technical leadership and guidance to thermal engineers and analysts.
  • Support project planning, task allocation, milestone tracking, risk identification and mitigation, and technical reviews with stakeholders.
• Documentation & Communication
  • Produce clear technical documentation: design reports, analysis results, trade studies, test reports, and presentations for internal and customer reviews.
  • Act as the primary thermal authority within the flight systems team for internal and external queries.
  • Design and implement processes and procedures as required.

Requirements

• Bachelor’s or master’s degree in aerospace, Mechanical, or related Engineering.
• Proven expertise in thermal systems design and analysis, including heat transfer (conduction, convection, radiation) and thermal control for flight environments.
• Experience leading thermal engineering efforts on complex aerospace projects (aircraft, spacecraft, UAVs).
• Strong knowledge of thermal simulation tools (e.g., Thermal Desktop, SINDA, FE/CFD tools) and experience validating models with test data.
• Excellent communication skills with the ability to articulate technical trade-offs to multidisciplinary teams.

Desirable

• Experience working on high‑altitude or space‑flight vehicles.
• Familiarity with thermal vacuum testing, flight qualification standards, and thermal materials.
• Prior leadership or project management experience in engineering environments.

What We Offer

• Location: Alton (Hampshire), UK.
• Contract: Permanent, 37.5 hours per week (excluding breaks). Hybrid working (where applicable), giving you the flexibility to balance time between home and our offices (norm is 3 days a week).
• Salary: Competitive – dependent on experience.
• Bonus: Non contractual company performance related bonus.
• Pension: 10% company contribution, plus salary exchange options for AVCs.
• Green Benefits: Access to our Green Car/EV scheme via salary exchange.
• Annual Leave: 25 days plus bank holidays (rising to 28 days after 3 years’ service).
• Employee Schemes: Eligibility for the BAE Systems Share Incentive Scheme, Company Performance Free Share awards, Cycle to Work scheme, and a Halfords Trade Discount Card.
• Community & Culture: Social and employee engagement activities through our Prismatic Pulse group.
• Wellbeing: Access to Occupational Health support, including an Employee Assistance Programme (EAP).

How to Apply

To apply, please send your CV and a covering email to . In your application, please confirm:

• That you have the right to work in the UK and can commute to the job’s location of work.
• That you have been a UK resident for at least 5 years and can meet any required background checks (or security clearance requirements where applicable).
• Your salary expectations for the role.
• Your availability or current notice period.

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