Construction Mechanical Engineer II

Relativity; Long Beach (CA); On-site; USD 90,000 - 130,000; Full time

Job summary

Relativity Space in Long Beach, CA is seeking a Mechanical Engineer to support the design and delivery of infrastructure and manufacturing systems critical to building our Terran R rockets. You will design mechanical systems, perform sizing and calculations, and develop documentation across AutoCAD and Revit models.

You will collaborate with cross-functional teams to ensure constructible, code-compliant designs and support projects from concept through commissioning and handoff.

Qualifications

• BS in Mechanical Engineering or related field.
• 2+ years in mechanical design for infrastructure, manufacturing, or commercial building systems.
• Experience with HVAC, hydronic/chilled water, plumbing and exhaust systems.

Responsibilities

• Design and develop mechanical systems including HVAC and plumbing.
• Perform calculations, sizing, load analyses, and performance evaluations.
• Create and maintain AutoCAD drawings, Revit models, and specs.
• Coordinate with engineering, construction, manufacturing, and facilities teams.
• Support projects from concept through construction, commissioning, and handoff.
• Review designs and submittals for codes, standards and safety.
• Conduct site inspections and resolve field challenges to meet timelines.
• Support startup, testing, commissioning, and continuous improvement.

Skills

Mechanical design

Engineering calculations

Systems coordination

Documentation

Project collaboration

Education

Bachelor of Science in Mechanical Engineering

Master's degree in Mechanical Engineering (nice to have)

Tools

AutoCAD

Revit

Job description

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 Construction Design and Delivery team is at the core of Relativity's growth and development. Through our collaboration and expertise, we deliver projects that lay the foundation for Relativity's future success. In essence, we build the factory that builds the rockets! We are responsible for cross functional relationships with reams such as Manufacturing, Propulsion, PBF, Avionics, Machine Shop, Facilities, EHS, and Security to name a few, working through design specification and execution of critical infrastructure projects that supports the mission of work centers. Our relationships don't stop there, working daily with government agencies, utility suppliers, vendors and contractors who support our factory build out. Our team ensures that all projects meet operational requirements, safety and environmental codes, all the while remaining within budget, delivering on time, and to the highest quality as we help to drive production forward.

About the Role:

• Support the design and development of mechanical systems, including HVAC, plumbing, process gas distribution, and specialized systems such as cryogenic, high-pressure, and oxygen monitoring systems.
• Perform engineering calculations, equipment sizing, load analyses, and system performance evaluations to support efficient, reliable, and code-compliant mechanical designs.
• Develop and maintain mechanical design documentation, including AutoCAD drawings, Revit models, Basis of Design narratives, technical specifications, and as-built drawings.
• Collaborate with cross-functional engineering, construction, manufacturing, and facilities teams to ensure mechanical systems are properly coordinated, constructible, and aligned with operational requirements.
• Support mechanical and plumbing projects from initial concept and design through construction, commissioning, and final handoff, including scheduling, budgeting, risk assessment, and documentation.
• Review designs, drawings, and submittals from external consultants and vendors to ensure compliance with applicable codes, industry standards, project specifications, and safety requirements.
• Conduct site inspections, troubleshoot technical issues, respond to RFIs, and coordinate with contractors and internal stakeholders to resolve field challenges and maintain project timelines.
• Support system startup, testing, commissioning, and continuous improvement initiatives to enhance the efficiency, reliability, and maintainability of manufacturing and office facilities.

About You:

• Bachelor of Science degree in Mechanical Engineering or a related engineering field.
• Minimum 2+ years of experience in mechanical design and engineering for infrastructure, manufacturing, or commercial building systems.
• Experience in the design and specification of HVAC, hydronic/chilled water, plumbing, drainage, compressed air, and exhaust systems.
• Experience developing Basis of Design (BOD) documentation, mechanical load calculations, and equipment sizing.
• Familiarity with mechanical codes and standards, including ASHRAE, Title 24, NFPA, and Uniform Plumbing Code (UPC).
• Experience in creating and reviewing permit-ready mechanical drawings and specifications.

Nice to have but not Required:

• Master's degree in Mechanical Engineering or related field.
• Engineer In Training (EIT) Certification.
• LEED GA or LEED AP accreditation.
• Background in supporting cleanroom ventilation, specialty gas systems, or critical environment design.

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