Principal Propulsion Engineer, Blue Thrusters

Applications will be accepted on an ongoing basis until the requisition is closed.

At Blue Origin, we envision millions of people living and working in space for the benefit of Earth. We’re working to develop reusable, safe, and low-cost space vehicles and systems within a culture of safety, collaboration, and inclusion. Join our team of problem solvers as we add new chapters to the history of spaceflight! This role is part of the Blue Origin Engines business unit, where our focus is the design, development, manufacturing, and testing of engines and propulsion systems.

Built for multiple uses, our family of engines is powering the next generation of rockets for commercial, civil, national security, and human spaceflight.

• Design, analyze, and develop thruster combustion devices, including injectors and chambers, with a focus on performance, combustion stability, and thermal behavior
• Contribute to thruster-level design work that integrates combustion devices, propellant valves, feed system interfaces, and drive electronics
• Perform and review performance, stability, thermal, and transient analyses, and correlate results with test data to improve designs
• Develop a working understanding of valve capabilities and limitations (response time, flow characteristics, leakage, actuation type, and operating environment) and partner with the valve engineers on requirement and interface definition
• Plan and support thruster hot-fire test campaigns, including test article definition, instrumentation, test execution, and data review
• Investigate anomalies and failures from root cause through corrective action, applying first-principles analysis
• Drive engineering trade studies with sound analysis and clear recommendations
• Develop and improve analysis tools and practices, such as performance and stability codes, hot-fire data trending, and data reduction and plotting tools
• Mentor and coach engineers on injector and chamber design, analysis, hot-fire testing, and data review
• Collaborate with systems, vehicle, electrical, software, manufacturing, and test operations teams to define interfaces and resolve integration issues early
• Identify technical risks early and communicate them clearly to your team and leadership
• Author and review technical reports, test plans, qualification documentation, and engineering specifications

• B.S. or higher in Aerospace Engineering, Mechanical Engineering, or a related technical field
• 10+ years of experience in liquid rocket engine or spacecraft thruster development
• Hands-on experience designing and analyzing injectors and thrust chambers, including performance, combustion stability, and thermal analysis
• Experience planning, conducting, and analyzing results from hot-fire testing of liquid propulsion hardware
• Solid understanding of propellant valves (solenoid, pneumatically actuated, or similar) and how valve characteristics affect ignition, start and shutdown transients, pulsing performance, and overall thruster behavior
• Experience supporting technical failure investigations and implementing design corrections
• Ability to work across disciplines and make sound technical decisions with incomplete information
• Strong communication and interpersonal skills, with experience mentoring other engineers
• Must be a U.S. citizen or national, U.S. permanent resident (current Green Card holder), or lawfully admitted into the U.S. as a refugee or granted asylum

• M.S. in Mechanical Engineering, Aerospace Engineering, or a related field
• Experience with thruster or engine hardware that has progressed from clean sheet through qualification and flight
• Experience with cryogenic propellants (e.g., LOX, LNG, LH2),…