Senior Thermal Engineer

Icarus was founded on the belief that the Stratosphere is the Forgotten Frontier and that reclaiming it will define the next era of aerospace and what is possible from the sky. We build solar-powered aircraft that fly at 60,000 ft for weeks at a time, delivering persistent, affordable, and scalable presence from this layer of the atmosphere.

Mission

Re-establish and maintain dominance in the Stratosphere.

What you’ll do

• Own thermal design of the aircraft, from first-order sizing through validation against altitude chamber and flight data.
• Model at the fidelity the decision requires — hand calculations and 1-D networks early, CFD and FEA when warranted.
• Own battery thermal management: insulation, heater sizing, and cold-soak survival. This is the constraint that sets our endurance.
• Deliver thermal solutions for avionics, powertrain, and payloads against aggressive mass targets, and select the materials, coatings, and interfaces to get there.
• Quantify how temperature drives the power budget. Solar cell, battery, and motor efficiency all move with temperature, and your analysis feeds the energy balance that keeps the aircraft up.
• Define and run thermal testing: setups, instrumentation, procedures, and correlation of models to measured data.
• Work across structures, avionics, power, and manufacturing, and present thermal status at design and failure reviews.

What we’re looking for

• 3+ years in thermal analysis or thermal design of flight, space, or high-reliability hardware, with a degree in mechanical, aerospace, or another engineering discipline.
• A thermal design you took from analysis through test and into flying hardware.
• Experience in low-convection environments where radiation dominates — spacecraft, high-altitude, or UAV.
• Strong 0-D and 1-D thermal network modeling, plus Thermal Desktop, ANSYS, Simcenter, or equivalent, and Python or MATLAB for tooling.
• Battery thermal management experience: pack-level modeling, heater strategies, and cold-soak survival.
• Hands-on test experience with thermal-vacuum or altitude chambers, instrumentation, and model correlation.
• Comfort working on the floor with hardware and technicians. Onsite in El Segundo; this role is not remote.
• A serious commitment to feedback and growth, and the drive to perform in a fast-paced, high-intensity environment.

Why Icarus

1. Meaningful equity
2. Top market salary and bonuses
3. Health, dental, and vision insurance
4. Factory in El Segundo
5. Real ownership, real hardware, real flight
6. Small team, massive responsibility (but growing very fast)
7. High signal (engineering) to noise (management) culture
8. Dream desk setup
9. Daily lunch
10. Unlimited celsius

This is not a normal engineering job

1. We are pioneers, not corporate managers. Icarus deliberately optimizes for a high signal (engineers) to noise (management) ratio, where engineering, flight, and execution matter more than process, politics, or management overhead
2. You will work side by side with the CEO and a small team of world-class builders. You will own your subsystem end to end. Design it. Build it. Break it. Fix it. Validate it in the desert. Fly it. Then do it again, faster
3. We expect full extreme ownership. This is a high-trust, no-BS team, and everyone pulls their weight
4. We are hiring across the stack: mechanical, aerodynamics, RF, GNC, electrical, avionics, power electronics, energy storage, software, and systems
5. We want builders. No hand-holding. No fluff. No fake projects. No slide decks. No sitting in meetings all day. Just raw engineering, real hardware, and real flight
6. You must thrive under pressure, learn fast, troubleshoot in the field, and push hardware to its limits. We move fast. We go to Mojave at 4 am in the morning. We expect results and an obsession with quality and speed
7. You will be a core executor of flight systems, taking them from concept to reality and driving rapid iteration loops. You will work across design, integration, testing, and flight. If you want real ownership, real hardware, and real flight milestones, this is it.

No tourists. No bystanders. Only builders.

Hiring process

1. Intro call
2. Interview with the CEO
3. Meet the team in-person

US salary range

$150,000 - $190,000 USD

The salary range for this role is an estimate based on a wide range of compensation factors, inclusive of base salary only. Actual salary may vary based on (but not limited to) work experience, education and/or training, critical skills, and/or business considerations. Highly competitive equity grants are considered part of Icarus' total compensation package.