Senior Propulsion Engineer - Own the solid rocket motor powering two interceptor platformsEl Segundo, California | On-site
Opportunity SummaryThis role owns the solid rocket motor across two interceptor products, covering requirements, grain design, case, nozzle, igniter, static fire, and flight. You will report directly to the technical co-founder and serve as the propulsion authority on the program.
The motor must deliver the total impulse and thrust profile the vehicle needs, fit within the dimensional limits of existing launch systems, and survive the full storage and flight environment. You will partner closely with the founders and with mechanical, GNC, aerodynamics, and avionics engineers, and you will guide the propulsion engineers who join the team as the program scales.
About UsWe are a seed-stage, venture-backed defense technology company building affordable, modular interceptors for air and missile defense, with surface-launched and space-based platforms in development. The team has already demonstrated autonomous intercepts and is moving quickly from prototype hardware into flight testing from our South Bay facility. We are a small group of engineers and operators who design, build, and test in-house, with a clear path toward scaled production for government customers.
Job Duties- Translate trajectory needs from GNC and aerodynamics into motor requirements such as total impulse, thrust profile, burn time, and mass
- Lead motor architecture and detailed design across grain, case, insulation and liner, nozzle, and igniter
- Design propellant grains and perform burnback analysis to tailor the thrust curve
- Model internal ballistics, chamber pressure, heat transfer, and nozzle erosion
- Select propellant formulations, insulation, and nozzle materials
- Drive make-vs-buy decisions for propellant and motor components, and manage motor suppliers
- Co-design the motor case with the mechanical team for pressure, launch loads, and airframe attachment
- Plan and execute static fires, proof and pressure tests, and temperature-conditioned firings
- Coordinate with outside test ranges and energetics facilities, and own handling and storage safety procedures
- Design test fixtures and instrumentation, and analyze data to refine the design
- Take the motor through qualification for storage, transport, and flight environments
- Define the ignition train interface with avionics, including safe-and-arm devices and interlocks
- Provide thrust and performance models for the 6DOF simulation, and support thrust vector control if adopted
- Work with aerodynamics on plume and base drag effects, and support flight test predictions and post-flight analysis
- Mentor and review the work of propulsion engineers
Qualifications- Bachelor's degree in aerospace, mechanical, or chemical engineering, or a related field (master's preferred)
- 5+ years of solid rocket motor development experience
- Has carried at least one solid motor from concept through static fire, including grain, nozzle, and igniter integration
- Strong command of internal ballistics, combustion, heat transfer, and pressure vessel design
- Hands-on static fire operations, instrumentation, and test data analysis experience
- Working knowledge of safe handling and storage of energetic materials
- U.S. Person status required (ITAR) and ability to obtain a U.S. security clearance
Preferred Experience- Tactical missile or interceptor motor experience
- Solid propellant chemistry and casting and curing processes
- Composite motor cases or thrust vector control
- Motor qualification, MIL-STD-810 environmental testing, or insensitive munitions testing
- High-speed DAQ, strain gauges, thermocouples, and high-speed imaging
- Hands-on machining and test fixture design
- Prior early-stage startup experience
Why Join Us- Be the propulsion owner on two interceptor platforms, reporting directly to company leadership
- Take a motor from clean-sheet design through static fire and flight
- Build and lead the propulsion function as the team grows
- Fast decision cycles with minimal bureaucracy
- Early equity in a seed-stage company with a rapidly growing team
- Mission with direct national security impact
Compensation Details$140,000 - $180,000 + equity
