About the role
Spacecraft represent the most pressing unmet need across the entire aerospace industry. As more launch vehicles come online and the cost to orbit decreases, more companies launching payloads to space continue to emerge. For the first time in history, this influx of payload companies combined with reduced launch costs has resulted in a massive increase in need for commercial spacecraft platforms, known as satellite buses. These buses hold the payloads of our customers and are flown on launch vehicles. Apex manufactures these satellite buses at scale using a combination of software, vertical integration, and hardware that is designed for manufacturing. Our spacecraft enable the future of society: ranging from earth observation to communications and more. We’d love for you to join us on our mission of providing humankind access to the galaxy beyond our planet.
About
the Role Apex is seeking a Propulsion Mechanical Engineer to own mechanical designs for our spacecraft propulsion systems. You will drive the design, analysis, and qualification of propulsion hardware that must perform reliably through launch environments and long-duration on-orbit operations. This role spans mechanical design, fluid system development, thermal interfaces, and flight hardware qualification, with end-to-end ownership from early concept through flight readiness and operational performance. You will work closely with propulsion, thermal, avionics, and systems engineering teams to deliver robust, repeatable propulsion hardware designed for production spacecraft.
Responsibilities: Own the mechanical design of propulsion system hardware and its integration into propulsion modules, including thrusters, PPUs, manifolds, flow control hardware, high-pressure propellant lines, and tanks. Perform analysis and testing to satisfy propulsion subsystem
requirements across performance, safety, and environmental constraints. Design propulsion module structures and housings, plasma-facing components, mounts, thermal straps, and mechanical interfaces. Perform structural and vibration analyses to support launch loads, thermal cycling, and long-duration on-orbit operation. Generate and maintain CAD models, drawings, and GD&T for flight hardware. Support manufacturing, assembly, and integration of propulsion and fluid hardware. Plan and execute propulsion hardware testing, including vacuum testing, performance testing, leak testing, proof pressure testing, vibration, and thermal vacuum qualification. Diagnose test anomalies related to propulsion system testing and drive corrective action and design iteration. Partner with systems engineering on