Senior Mechanical Engineer

At Relativity Space, we’re building rockets to serve today’s needs and tomorrow’s breakthroughs. Our Terran R vehicle will deliver customer payloads to orbit, meeting the growing demand for launch capacity. But that’s just the start.

Achieving commercial success with Terran R will unlock new opportunities to advance science, exploration, and innovation, pioneering progress that reaches beyond the known. Joining Relativity means becoming part of something where autonomy, ownership, and impact exist at every level. Here, you're not just executing tasks; you're solving problems that haven’t been solved before, helping develop a rocket, a factory, and a business from the ground up.

Whether you’re in propulsion, manufacturing, software, avionics, or a corporate function, you’ll collaborate across teams, shape decisions, and see your work come to life in record time. Relativity is a place where creativity and technical rigor go hand in hand, and your voice will help define the stories we’re writing together. Now is a unique moment in time where it’s early enough to leave your mark on the product, the process, and the culture, but far enough along that Terran R is tangible and picking up momentum.

The most meaningful work of your career is waiting. Join us.

About The Team

The Stennis Test team designs, builds, and operates test sites to evaluate Terran R's high-energy components, rocket engines, and both booster and upper stages. Team members are hands-on with these large-scale, complex systems, pushing hardware to the limits and directly contributing to flight readiness. The work is fast-paced, highly operational, and collaborative.

No aerospace experience required—we welcome fresh graduates as well as those with hands-on backgrounds in aviation, automotive, manufacturing, offshore operations, industrial systems, construction, or adjacent industries. As the Stennis Test site scales to meet growing demand, the team plays a critical role in paving the way for routine, reliable flights of Terran R.

About The Role

As a Senior Propulsion Test Engineer, you will work with test stands and test articles (high-energy components, engines, and full stages) for Terran R. You'll have the opportunity to see a heavy-lift orbital launch vehicle and its many parts come to life through testing. Test and flight articles are designed and built in our Long Beach factory, then sent to Stennis to undergo rigorous testing.

You'll solve a variety of technical problems across broad ranges of timeframe, complexity, and impact, and continuously improve processes to move faster and more efficiently. The role includes three focus areas - Design Build, Operations, and Integration. You'll initially be placed on a team in one focus area, with opportunities to work across focuses as you develop in the role, particularly between Operations and Integration which work closely together.