Icarus is seeking a Senior Thermal Engineer to own the thermal design of solar-powered high-altitude aircraft. You will be responsible for battery thermal management, avionics and payload thermal solutions, and quantifying temperature effects on the power budget. The role involves modeling, testing, and cross-functional collaboration to deliver flight-ready hardware.

Responsibilities

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.

Requirements

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.

Benefits

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