Senior Propulsion Engineer - Solid Rocket Motors

Overview

You will own the solid rocket motor for our two interceptor platforms. That covers everything from motor requirements and grain design to the case, nozzle, igniter, static fire, and flight. You’ll report to the CTO.

The motor has to deliver the impulse and thrust profile the interceptor needs while fitting the size limits of existing launchers and surviving the full range of storage and flight environments. You’ll work directly with the founders and with the mechanical, GNC, aerodynamics, and avionics engineers.

What You’ll Do

Own motor requirements and design

• Work with GNC and aerodynamics to turn trajectory needs into motor requirements, including total impulse, thrust profile, burn time, and mass.
• Lead the motor architecture and design, including the grain, case, insulation and liner, nozzle, and igniter.
• Design propellant grains and run burnback analysis to shape the thrust curve.
• Model internal ballistics, chamber pressure, heat transfer, and nozzle erosion.

Select materials and suppliers

• Select propellant formulations, insulation, and nozzle materials.
• Lead decisions on whether to buy propellant and components or produce them in-house, and manage motor suppliers.
• Design the motor case with the mechanical team, covering pressure loads, launch loads, and attachment to the airframe.

Test and qualify

• Plan and run static fires, pressure tests, and temperature-conditioned tests.
• Work with external test ranges and energetics facilities, and own safety procedures for handling and storing energetic materials.
• Design test fixtures and instrumentation, and analyze test data to improve the design.
• Lead the motor through qualification for storage, transport, and flight environments.

Integrate with the vehicle

• Work with avionics on the ignition train interface, including safe-and-arm devices and safety interlocks.
• Work with GNC on thrust profiles and motor performance models for the 6DOF simulation. [Support thrust vector control, if selected.]
• Work with aerodynamics on plume effects and base drag.
• Support flight tests, including pre-flight predictions and post-flight performance analysis.

Required Qualifications

• B.S. in Aerospace, Mechanical, or Chemical Engineering, or a related field. M.S. preferred.
• 5+ years of solid rocket motor development experience.
• Has taken at least one solid rocket motor from concept through static fire, including grain design, nozzle, and igniter integration.
• Strong grasp of internal ballistics, combustion, heat transfer, and pressure vessel design.
• Hands-on test experience, including static fire operations, instrumentation, and data analysis.
• Working knowledge of safe handling and storage of energetic materials.
• Must be a U.S. person as defined by ITAR (U.S. citizen, lawful permanent resident, or protected individual). [Must be eligible to obtain a U.S. security clearance.]

Nice to Have

• Experience with tactical missile or interceptor motors.
• Familiarity with solid propellant chemistry and casting and curing processes.
• Experience with composite motor cases or thrust vector control.
• Experience with motor qualification, environmental testing (e.g., MIL-STD-810), or insensitive munitions testing.
• Experience with high-speed DAQ, strain gauges, thermocouples, and high-speed cameras.
• Hands-on build experience, including machining and test fixture design.
• Prior early-stage startup experience.

Compensation

The base pay range for this role is $140,000 – $170,000 per year.