GNC Simulation Engineer I

Relativity Space•Long Beach, CA

9h•$110,000 - $164,000

About The Position

Relativity Space is building rockets to serve today’s needs and tomorrow’s breakthroughs. Their Terran R vehicle will deliver customer payloads to orbit, meeting the growing demand for launch capacity. Joining Relativity means becoming part of something where autonomy, ownership, and impact exist at every level. You will be solving problems that haven’t been solved before, helping develop a rocket, a factory, and a business from the ground up. Whether 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. The Guidance, Navigation, and Control (GNC) and Performance teams are responsible for defining and analyzing how Terran R flies, from liftoff to landing. The work combines a variety of disciplines such as advanced modeling, orbital mechanics, software development, and dynamic systems to optimize every phase of flight. You’ll develop flight algorithms, simulate trajectories, and model Terran R’s dynamic behavior across mission profiles. Whether you're early in your career or a seasoned expert, you’ll have the opportunity to own critical pieces of the system, influence design, and see your work fly. The department is part of the Integrated Performance team, uniting key disciplines to drive performance at every stage of the mission.

Requirements

An undergraduate or graduate degree (BS/MS/PhD) in engineering, physics, mathematics or related disciplines
Proficiency with compiled (e.g. C++, Rust) and scripted (e.g. Python) languages
Experience developing physics-based simulations
Relevant student team, research, internship, or full-time experience
Ability to work in a fast paced and intense startup environment
Ability to complete projects with ownership of end-to-end solutions with a high degree of independence

Nice To Haves

Familiarity with the design and analysis of launch vehicles or space systems
Experience developing aerospace vehicle simulations that interface with GNC algorithms and/or hardware-in-the-loop (HITL) testing
Experience implementing high-performance computing (HPC) solutions
Experience implementing software development practices and workflows such as Docker, continuous integration (CI), and continuous deployment (CD)

Responsibilities

Be a key contributor to the 6DOF simulation used for GNC algorithm development, Monte Carlo analysis, and hardware-in-the-loop (HITL) testing
Work with analysis and hardware teams to develop and integrate subsystem models into the 6DOF simulation
Implement numerical solvers and physics models
Develop simulation configuration, scheduling, logging, and Monte Carlo capabilities
Develop simulation interfaces with GNC algorithms
Maintain and improve the development environment for simulation users
Contribute to other cross-functional software packages at Relativity