Engine Responsible Engineer

About the Role

Orbital Operations is seeking an Engine Responsible Engineer to own the end-to-end development of our large liquid-oxygen/liquid-hydrogen rocket engine system.

This is a senior, hands-on technical leadership role for someone who has previously supported a large cryogenic engine through design, development, integrated testing, and major hot-fire campaigns. You will serve as the directly responsible engineer for the engine and guide the program from its current architecture through development, qualification, and flight.

Your ownership will extend across the complete engine system, including tubing and plumbing, P&IDs, turbomachinery, combustion devices, valves, instrumentation, controls interfaces, test operations, data review, and anomaly resolution. You will define the engine development roadmap, identify the most important risks, and determine how analysis and testing should be used to retire them.

The work will vary significantly from day to day. You may spend one day reviewing engine-system performance, another routing flight tubing or defining a test sequence, and the next sitting on console for a hot-fire test. As the vehicle program progresses, you will also have the opportunity to define stage-test objectives, develop flight concepts of operations, and support launch operations from console.

This position requires deep technical experience, but also the curiosity to continually learn about the vehicle, ground systems, avionics, structures, and other systems that interface with the engine. You should be a self-starter who can create direction where it does not yet exist, lead collaborative projects to completion, and maintain technical rigor while moving on an ambitious schedule.

Responsibilities

Engine Ownership and Program Direction

• Serve as the Responsible Engineer and primary technical owner for the main engine from development through qualification and flight.
• Establish and continuously refine the engine development strategy, technical priorities, test progression, and criteria for advancing between program phases.
• Maintain a system-level understanding of the complete engine, including combustion devices, turbomachinery, valves, ignition, tubing, instrumentation, controls, and thermal management.
• Identify the engine program’s most important technical risks and develop focused analysis and test plans to retire them.
• Make technical trades across performance, mass, reliability, schedule, cost, manufacturability, operability, and test risk.
• Provide clear technical direction to the engineers, technicians, suppliers, and partner teams contributing to the engine.
• Communicate engine status, risks, test results, decisions, and resource needs to company leadership.
• Create and own projects that improve the team’s technical capability, development speed, and collective efficiency.

Fluid Systems, P&IDs, and Tubing

• Own engine-level fluid schematics, P&IDs, pressure budgets, operating states, and interface documentation.
• Own the design and integration of engine tubing and plumbing systems.
• Establish tubing requirements for sizing, routing, pressure drop, thermal contraction, flexibility, vibration, supports, joints, cleanliness, inspectability, manufacturability, assembly, and serviceability.
• Define and maintain engine interfaces with propellant tanks, vehicle feed systems, pressurization systems, ground-support equipment, and test infrastructure.
• Review fluid-system analyses involving pressure loss, flow distribution, chilldown, cavitation margin, two-phase behavior, thermal conditioning, and transient response.
• Ensure the physical engine configuration accurately reflects the released P&IDs, analyses, procedures, and test configuration.

Engine Development and Analysis

• Apply engineering fundamentals in fluid mechanics, thermodynamics, heat transfer, combustion, and structural mechanics to solve engine-development problems.
• Define engine operating envelopes, performance requirements, startup and shutdown sequences, conditioning procedures, redlines, and abort criteria.
• Lead or review engine-system analyses, simulations, and trade studies.
• Support subsystem troubleshooting and investigations involving combustion devices, turbomachinery, valves, heat exchangers, instrumentation, ignition systems, and controls.
• Partner with avionics, vehicle, structures, thermal, manufacturing, and test teams to investigate cross-functional technical issues.
• Translate test results and operational experience into improved designs, models, procedures, and requirements.

Test Campaign Ownership

• Serve as the Responsible Engineer for engine and propulsion-system test articles.
• Define component, subsystem, and integrated engine test campaigns in collaboration with hardware owners and partner teams.
• Establish clear test objectives, configurations, instrumentation requirements, test matrices, success criteria, and data-review expectations.
• Author and approve test plans, procedures, sequences, redlines, and readiness documentation.
• Lead test readiness reviews, pre-test briefings, real-time technical decision-making, and post-test data reviews.
• Sit console during cold-flow, component, subsystem, and hot-fire testing.
• Own the exploratory operation of new and existing engine designs, including the controlled expansion of operating envelopes.
• Review test data to evaluate combustion performance, turbomachinery behavior, valve timing, thermal response, system stability, hardware health, and overall engine performance.
• Troubleshoot technical issues during test campaigns and determine whether testing should proceed, pause, or change direction.
• Lead anomaly investigations and root-cause analyses, then ensure corrective actions are incorporated into the design or operating approach.
• Maintain configuration control and traceability across design revisions, manufacturing deviations, test articles, and flight hardware.

Hands-On Execution

• Work directly with test articles and flight hardware during assembly, integration, checkout, and troubleshooting.
• Support activities such as leak checks, proof testing, cleanliness verification, instrumentation checkout, and functional testing.
• Write or review test sequences, data-processing scripts, analysis tools, and automated health-monitoring methods.
• Design tooling, fixtures, instrumentation installations, or temporary test hardware when necessary to keep development moving.
• Work closely with manufacturing and suppliers to ensure engine hardware can be built, inspected, assembled, tested, serviced, and repeated reliably.
• Demonstrate the ability to execute high-ownership projects on ambitious schedules, including developing unconventional solutions when appropriate.

Stage Testing and Flight Operations

• Support integrated stage and vehicle test campaigns as the propulsion system matures.
• Define propulsion-related stage-test objectives, instrumentation requirements, operating limits, and success criteria.
• Develop engine and propulsion concepts of operations for ground testing, launch, ascent, in-space operation, safing, and contingency scenarios.
• Participate in vehicle-level readiness reviews and mission simulations.
• Support launch and flight operations from console as the engine or propulsion Responsible Engineer.
• Review stage and flight data and use the results to guide continued engine development and certification.

Minimum Qualifications

• Bachelor’s degree in mechanical engineering, aerospace engineering, or another relevant science, engineering, technology, or mathematics field.
• Significant experience developing liquid rocket engines or similarly complex, high-performance cryogenic propulsion systems.
• Direct experience supporting a large cryogenic rocket engine through multiple phases of development and integrated testing.
• Demonstrated technical ownership of a complete engine, major engine subsystem, or propulsion test campaign.
• Strong understanding of liquid rocket engine systems, cryogenic fluid behavior, thermodynamics, fluid mechanics, and heat transfer.
• Experience developing and reviewing P&IDs, fluid schematics, pressure budgets, operating sequences, and system-interface documentation.
• Experience designing tubing and plumbing for cryogenic, high-pressure, high-vibration, or high-temperature applications.
• Experience planning and executing propulsion tests, defining instrumentation, sitting console, reviewing data, and resolving anomalies.
• Ability to move effectively between analysis, detailed design, manufacturing, hardware integration, and test operations.
• Demonstrated ability to lead collaborative, high-ownership projects through completion on ambitious schedules.
• Strong problem-solving skills and the ability to make technically sound decisions with incomplete information.
• Willingness to work hands-on with hardware and support testing or flight operations outside normal working hours when required.

Nice to Have

• Experience with pump-fed LOX/LH2 rocket engines.
• Experience with expander-cycle or dual-expander-cycle engines.
• Experience with large engine hot-fire campaigns and the progressive expansion of engine operating envelopes.
• Experience with combustion devices, turbomachinery, cryogenic valves, heat exchangers, ignition systems, or high-speed instrumentation.
• Experience with engine startup transients, chilldown, cavitation, combustion stability, thermal management, and turbomachinery dynamics.
• Experience developing additively manufactured thrust chambers, injectors, manifolds, or turbomachinery components.
• Experience with clustered-engine or multi-thrust-chamber architectures.
• Experience defining engine acceptance, qualification, certification, reuse, or flight-readiness requirements.
• Experience with stage testing, launch operations, mission simulations, or flight-data review.
• Experience writing data-analysis code or developing engine-system simulations.
• Experience building propulsion hardware or technical organizations in an early-stage company.

What Success Looks Like

Within the first year, you will have:

• Established a credible engine development, testing, and qualification roadmap.
• Taken clear technical ownership of the engine architecture and the direction of the propulsion program.
• Brought the engine’s P&IDs, tubing design, interfaces, operating sequences, and test configurations under disciplined configuration control.
• Defined and executed test campaigns that systematically retire the engine’s highest technical risks.
• Built an effective process for test readiness, console operations, data review, anomaly resolution, and rapid design iteration.
• Improved the team’s ability to turn test data into reliable technical decisions.
• Developed a clear path from individual engine testing to integrated stage testing and flight operations.
• Built confidence across the company that the engine has an accountable technical owner who understands the complete system and can deliver flight-ready hardware.