Thermal Engineer, Environmental Control Systems

About the Team

The Thermal Engineering team's work is essential to support our rapid innovation cycle and maintain the performance and reliability of advanced defense technologies. Thermal Engineers own the full development life cycle from conceptual design through prototyping, ground and flight testing, and operational deployment, ensuring high-performance, resilient systems that meet the demands of complex, contested environments.

About the Role

We are looking for a Thermal Engineer in Costa Mesa, CA to own the thermal management and environmental control systems (ECS) of air vehicles and other advanced defense platforms. You will apply a deep understanding of heat transfer, fluid dynamics, and thermal systems to keep avionics, payloads, power, and propulsion subsystems within their limits across the full mission envelope, from hot-day ground operations to high-altitude flight.

What You'll Do

• Own the thermal design and analysis of vehicle thermal management and ECS—air-cycle, ram-air, bleed-air, and liquid cooling loops—from component and cold plate level up through the full vehicle.
• Use first principles to discern the right level of analysis, running hand calcs, spreadsheets, and MATLAB/Python first-order models before detailed design.
• Define thermal management architecture and heat-sink strategy—ram-air and air-cycle cooling, vapor-cycle systems, liquid coolant loops, fuel as a heat sink, and thermal energy storage—to keep equipment within limits as heat loads scale.
• Size and rate heat exchangers, cold plates, pumps, fans, and valves, and evaluate vendor hardware against system requirements.
• Develop steady-state and transient system models of coolant, fuel, hydraulic, and lubrication circuits in tools such as Simcenter Amesim, Simscape, or GT-SUITE to predict performance across ground, climb, cruise, and off-nominal conditions.
• Work with avionics, propulsion, power, structures, and systems engineers to characterize heat loads and define thermal requirements and interfaces across operating and failure modes.
• Weigh thermal architectures against performance, weight, power draw, reliability, and cost, driving trade studies that balance thermal margin with vehicle-level impact.
• Own the thermal system models, correlate them to test and flight data, and set red/yellow limits for test and operation.
• Lead prototype builds, ground testing, and validation of thermal management and ECS designs (CAD, sensor and DAQ selection, data post-processing, results).
• Present thermal status and tradeoffs at internal and customer reviews with a clear view of timelines and technical status.
• Develop internal tools to improve analysis effectiveness and efficiency.
• Support failure reviews and root-cause analysis with test data and thermal analysis.

Required Qualifications

• MS or PhD in Mechanical Engineering, Aerospace Engineering, Applied Physics, or a related field with a focus on heat transfer, fluid dynamics, thermal sciences, or thermal systems
• Strong first-principles understanding of heat transfer and fluid dynamics, including conduction, convection, radiation, fluid flow, and transient thermal behavior
• Experience using thermal analysis, modeling, simulation, and/or physical test data to drive design decisions for passive or active thermal management systems
• Ability to communicate technical tradeoffs clearly across engineering, program, and customer stakeholders
• Ability to obtain and hold a U.S. Top Secret security clearance

Preferred Qualifications

• Experience with thermal system modeling software such as Simcenter Amesim, Simscape, or GT-SUITE
• Experience using MATLAB, Python, spreadsheets, or similar tools for first-order thermal modeling, transient analysis, or engineering trade studies
• CAD experience with Siemens NX, SolidWorks, or comparable tools
• Experience with thermal management, environmental control systems (ECS), air-conditioning, bleed-air, or ram-air systems
• Experience with analysis and modeling of hydraulic, fuel, coolant, or lubrication circuits
• Experience with heat exchanger sizing and rating