Senior Propulsion Engineer, Hall-Effect Thrusters Verified today

About the Role

Apex is seeking a Senior Electric Propulsion Engineer with deep expertise in Hall-effect thrusters to own the design, development, qualification, and production of Hall thruster technology for our electric propulsion systems. This is a senior individual contributor role with significant technical ownership and leadership scope.

You will drive key Hall thruster design decisions, lead test and life-qualification campaigns, and work alongside propulsion engineers as we scale electric propulsion production. You'll approach Hall thruster development with a production-first mindset and directly shape the hardware, processes, and infrastructure required to take it from development into flight and serial production.

Responsibilities

• Own the end-to-end design and development of Apex's Hall-effect thrusters, including discharge channel geometry, magnetic circuit design, anode and gas distributor design, and thermal-mechanical packaging.
• Develop plasma physics and performance models to drive thruster design, including ionization and acceleration behavior, magnetic field topology, efficiency, thrust-to-power, and specific impulse across the operating envelope.
• Define and execute thruster test and life-qualification campaigns, including performance mapping, plume characterization, thermal testing, oscillation and stability characterization, wear testing, and long-duration life testing in vacuum facilities.
• Develop erosion, degradation, and life models for the discharge channel and pole pieces and demonstrate compliance with mission life and propulsion budgets for power, thermal, throughput, and leak.
• Drive cathode-thruster coupling and overall electric propulsion system integration in partnership with cathode, propellant feed-system, and PPU owners.
• Select materials and processes, including ceramics, magnetic materials, and refractory metals, and qualify them for spaceflight and scalable production.
• Optimize thruster designs for performance, mass, cost, manufacturability, and repeatability, and develop the work instructions, process flows, and AI&T procedures required to build them at rate.
• Partner with systems, power electronics, thermal, structures, and avionics teams to define interfaces and verify requirements.
• Support the build, integration, and test of flight hardware, as well as launch campaigns, on-orbit performance evaluation, and anomaly resolution.
• Lead and contribute to failure analysis, root-cause investigations, and continuous design improvements to support future builds and scalable production.
• Provide technical mentorship to propulsion engineers and contribute to the continued development of Apex's Hall thruster and electric propulsion capability.

Required Qualifications

• Bachelor's degree in aerospace, mechanical, electrical, plasma/propulsion engineering, applied physics, or a related field.
• 6+ years of relevant electric propulsion experience with a Bachelor's or Master's degree, OR a Ph.D. in electric propulsion, plasma physics, applied physics, or a closely related field with 3+ years of relevant industry experience, with substantial and demonstrable focus on Hall-effect thruster design, development, and testing.
• Deep, hands-on knowledge of Hall thruster physics and design, including discharge channel design, magnetic circuit layout, anode and gas distribution, cathode coupling, and thermal management.
• Experience planning and executing Hall thruster or electric propulsion test campaigns in vacuum facilities, including plasma/plume diagnostics, performance measurement, and life/wear testing.
• Strong understanding of the failure and degradation mechanisms that drive Hall thruster life, including channel and pole erosion, thermal limits, and discharge instabilities, and how to design and test against them.
• Working knowledge of spacecraft propulsion system architecture, propellant feed systems, and PPU interaction.
• Experience owning hardware through design, development, build, and test.
• Ability to decompose requirements and ICDs and communicate clearly across engineering disciplines.
• Must be a U.S. Person (U.S. citizen, lawful permanent resident, or protected individual) as defined by ITAR (22 CFR §120.15).

Nice to Have

• Direct experience taking a Hall thruster from development through flight qualification and on-orbit operation.
• Experience with magnetically shielded, wall-less, and/or unshielded Hall thruster architectures.
• Experience with alternative propellants, including krypton and other non-xenon electric propulsion propellants, and their effects on thruster performance and life.
• Familiarity with Hall thruster plasma simulation tools, including particle-in-cell and hybrid codes, and magnetic FEA.
• Familiarity with PPU/thruster drive electronics and power interface definition.
• Design-for-manufacturing experience bringing propulsion hardware into serial or high-rate production.
• Experience with electric propulsion environmental qualification, including vibration, TVAC, and EMI testing of flight propulsion hardware.
• Experience supporting failure investigations and resolving issues on flight or qualification hardware.

What We Offer

• Equity in Apex
• 100% company-paid medical, dental, and vision for you and your dependents, plus $100k life insurance at no cost
• Comprehensive PTO package starting at 15 days vacation, growing to 20+ days annually, plus 10 paid holidays
• 401(k) plan with 100% match on first 3%, 50% on next 2%
• 8 weeks paid parental leave plus childcare reimbursement up to $350/day for work-related travel
• Daily catered lunch and unlimited snacks
• Monthly office socials, pickleball tournaments, run club, and family gatherings
• Professional desk setup and tools
• Playa Vista office with in-person collaboration and work-life flexibility