GNC Simulation Engineer I New Long Beach, California, United States

Relativity Space, Inc.; Long Beach (CA); On-site; USD 110,000 - 164,000; Full time

Benefits offered by this job

Equity

PTO & sick leave

Parental leave

Learning stipend

Job summary

Relativity Space is seeking talented engineers to join the Guidance, Navigation, and Control (GNC) and Performance teams to define and analyze Terran R flight dynamics. You will develop flight algorithms, simulate trajectories, and model dynamic behavior across mission profiles, collaborating with propulsion, manufacturing, software, and avionics teams to push the boundaries of rocket technology.

The role offers ownership, fast-paced startup environment, and opportunities to contribute from

Qualifications

• Undergraduate or graduate degree in engineering, physics, mathematics or related disciplines.
• Proficiency with compiled (C++, Rust) and scripted (Python) languages.
• Relevant student team, research, internship, or full-time experience.

Responsibilities

• Be a key contributor to the 6DOF simulation used for GNC algorithm development, Monte Carlo analysis, and hardware-in-the-loop 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.

Skills

C++

Rust

Python

Education

BS/MS/PhD in engineering, physics, mathematics or related disciplines

Job description

At Relativity Space, we’re building rockets to serve today’s needs and tomorrow’s breakthroughs. OurTerran R vehicle will deliver customer payloads to orbit, meeting the growing demand for launchcapacity. But that’s just the start. Achieving commercial success with Terran R will unlock newopportunities to advance science, exploration, and innovation, pioneering progress that reaches beyondthe 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. Nowis a unique moment in time where it’s early enough to leave your mark on the product, the process, andthe culture, but far enough along that Terran R is tangible and picking up momentum. The mostmeaningful work of your career is waiting. Join us.

About the Team:

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.

About the Role:

• You will 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

About You:

• 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
• 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 but not required:

• 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)

At Relativity Space, we are committed to transparency and fairness in our compensation practices. Actual compensation will be determined based on experience, qualifications, and other job-related factors.
Compensation is only one part of our total rewards package. Relativity Space offers competitive salary and equity, a generous PTO and sick leave policy, parental leave, an annual learning and development stipend, and more!To see some of the benefits & perks we offer, please visit here.

Hiring Range:

$110,000 - $164,000 USD

We are an equal opportunity employer and value diversity at our company. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.

As defined in the ITAR, “U.S. Persons” include U.S. citizens, lawful permanent residents (i.e., Green Card holders), and certain protected individuals (e.g., refugees/asylees, American Samoans). Please consult with a knowledgeable advisor if you are unsure whether you are a “U.S. Person.”
The person hired will have access to information and items controlled by the International Traffic in Arms Regulation (ITAR), and, therefore, must either be a “U.S. person” as defined by those regulations or otherwise eligible for a federally issued export control license. To assist Relativity in assessing its export compliance obligations in relation to your application, please identify which statement best applies to you:

Voluntary Self-Identification

We are a federal contractor or subcontractor. The law requires us to provide equal employment opportunity to qualified people with disabilities. We have a goal of having at least 7% of our workers as people with disabilities. The law says we must measure our progress towards this goal. To do this, we must ask applicants and employees if they have a disability or have ever had one. People can become disabled, so we need to ask this question at least every five years.

Completing this form is voluntary, and we hope that you will choose to do so. Your answer is confidential. No one who makes hiring decisions will see it. Your decision to complete the form and your answer will not harm you in any way. If you want to learn more about the law or this form, visit the U.S. Department of Labor’s Office of Federal Contract Compliance Programs (OFCCP) website at www.dol.gov/ofccp .

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