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Salary: USD 150,000 - 190,000 / annual
Icarus is building solar-powered aircraft that operate at 60,000 feet for weeks at a time, establishing persistent presence in the stratosphere. As Senior Thermal Engineer, you will own the complete thermal design of the aircraft from first-order sizing through validation against altitude chamber and flight data.
Key responsibilities include:
- Thermal design ownership across the entire aircraft, using hand calculations and 1-D networks early, advancing to CFD and FEA when warranted
- Battery thermal management: insulation design, heater sizing, and cold-soak survival strategies (this is the critical endurance constraint)
- Thermal solutions for avionics, powertrain, and payloads against aggressive mass targets, including material and coating selection
- Quantifying temperature effects on power budget: solar cell, battery, and motor efficiency all vary with temperature and feed into the energy balance
- Defining and executing thermal testing: setups, instrumentation, procedures, and model correlation to measured data
- Cross-functional collaboration with structures, avionics, power, and manufacturing teams; presenting thermal status at design and failure reviews
Required qualifications:
- 3+ years in thermal analysis or thermal design of flight, space, or high-reliability hardware
- Degree in mechanical, aerospace, or related engineering discipline
- Demonstrated thermal design taken from analysis through test into flying hardware
- Experience in low-convection environments where radiation dominates (spacecraft, high-altitude, UAV)
- Strong 0-D and 1-D thermal network modeling; proficiency with Thermal Desktop, ANSYS, Simcenter, or equivalent
- Python or MATLAB for tooling and analysis
- Battery thermal management experience: pack-level modeling, heater strategies, cold-soak survival
- Hands-on test experience with thermal-vacuum or altitude chambers, instrumentation, and model correlation
- Willingness to work on the floor with hardware and technicians; must be onsite in El Segundo
Icarus operates as a high-signal engineering culture with minimal management overhead. You will work directly with the CEO and a small team of world-class builders, owning your subsystem end-to-end: design, build, break, fix, validate in the field, and fly. The team expects extreme ownership, fast learning, field troubleshooting, and obsession with quality and speed. This is a role for builders who thrive under pressure and want real hardware, real flight milestones, and rapid iteration.
