Senior Fluid Systems Engineer

Relativity Space; Long Beach (CA); On-site; USD 132,000 - 198,000; Full time

Benefits offered by this job

Competitive salary and equity

Generous PTO and sick leave

Parental leave

Learning & development stipend

Job summary

Relativity Space is seeking a Vehicle Fluid Systems Engineer to own the fluid subsystem architecture and its integration across design, analysis, and testing for Terran R. You will shape system control, sizing, and validation strategies while collaborating with multiple engineering disciplines.

You will apply thermodynamics, fluid dynamics, and heat transfer knowledge to guide hardware design, perform rigorous analyses, and support launch readiness through comprehensive testing and evaluation.

Qualifications

• Bachelor's degree in Mechanical Engineering or relevant field.
• 4+ years of experience working with fluids systems.
• Strong foundation in thermodynamics, fluid dynamics and heat transfer.
• Experience with fluid or thermal modeling tools.
• Proficiency in Python for scientific computing and data analysis.

Responsibilities

• Own the vehicle fluid subsystem architecture and schematics, including system control scheme, component selection and sizing.
• Perform fluid and thermal analyses, system sizing, and characterization using 1D steady-state and network methods.
• Lead and participate in system and hardware reviews with design and manufacturing teams.
• Define and support test objectives and campaigns to validate designs and enable successful launch.

Skills

Fluids systems

Thermodynamics

Fluid dynamics

Heat transfer

Python

System design

Data analysis

Education

Bachelor's degree in Mechanical Engineering

Tools

Fluid/thermal modeling tools

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 Stage Fluids team designs and delivers the propellant, pressurant, pneumatics, and other fluid systems that turn structures into functioning rockets. The team has full ownership across design, production, test, and flight, maintaining a holistic view of Terran R, focused not on isolated parts but integrated functionality. Working on-site at the factory means you're never far from the hardware, enabling rapid iteration and tight feedback loops across design and manufacturing. You won't just be handed requirements: you'll be expected to ask the right questions, collaborate with partners across the company, and ultimately find the best solutions for Terran R.

About the Role

As a Vehicle Fluid Systems Engineer, you will be responsible for the fluid system architecture and function for a given vehicle fluid subsystem. You will apply expertise in system architecture, systems operations, and fluid thermodynamics applications to guide hardware design, system analysis, manufacturing, validation and operations.

• Own the vehicle fluid subsystem architecture and schematics, including system control scheme, system and component selection and sizing
• Conducting fluid and thermal analyses, including system sizing and characterization using a variety of base analytical methods (1D steady-state, fluid networks, etc.)
• Leading and participating in system and hardware design and manufacturing reviews
• Defining and supporting test objectives and test campaigns to validate system design, system models and overall system performance including supporting integrated vehicle testing and launch

About You

• Bachelor's degree (Mechanical Engineering or relevant)
• 4+ years of experience working with fluids systems
• Experience applying engineering fundamentals in system design, thermodynamics, fluid dynamics, and heat transfer
• Experience with one or more fluid or thermal modeling tools for internal compressible and incompressible analysis
• Proficiency in Python or a similar programing language for scientific computing and automated test/simulation data analysis

Nice to haves, but not required

• Experience with launch vehicles and spacecraft

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.

• Competitive salary and equity, a generous PTO and sick leave policy, parental leave, an annual learning and development stipend, and more!

Hiring Range:

$132,000 - $198,000 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.