Staff Mechanical Engineer, Propulsion

Firestorm is hiring a Staff Mechanical Engineer, Propulsion who will own the propulsion systems that power our sUAS platforms—from small piston and heavy-fuel engines to the fuel, induction, ignition, and exhaust architectures that surround them. You will be responsible for engine selection, integration, calibration, and qualification across Firestorm’s fuel-based aircraft, translating mission endurance and performance requirements into producible powerplant solutions. This is a deeply hands-on, full-time role. You will spend time at the test stand, in the engine cell, and on the flight line. You will design and instrument test articles, develop ECU calibrations, investigate failures, and partner with airframe and systems engineering to make sure our propulsion systems deliver power, endurance, and reliability across the full operational envelope. What You’ll Do Own development and integration of both small piston engines and micro turbojet propulsion systems, including engine selection, inlet/exhaust configuration, fuel and ignition architecture, thrust and power characterization, and ground/flight test campaigns tailored to each propulsion type. Develop and execute engine test plans on test stands and in-flight: power and torque mapping, BSFC characterization, endurance runs, vibration surveys, and altitude/temperature performance testing. Lead engine calibration and tuning, including AFR targets, EGT management, ignition timing, and injector strategy on EFI-equipped powerplants; identify and mitigate single-injector maldistribution and other cylinder-to-cylinder variability. Design and analyze fuel systems—tanks, lines, pumps, filters, regulators, and fuel pressure management—across the full flight envelope, including negative-G and altitude effects. Investigate and root-cause propulsion anomalies (RPM collapse, lean events, misfires, mechanical failures); develop structured multi-phase test plans and drive corrective action. Specify and qualify propellers in coordination with aerodynamics, balancing thrust, efficiency, ground clearance, acoustic signature, and vibration. Develop and maintain propulsion engineering documentation: interface control documents, test plans and reports, propulsion budgets (power, fuel burn, endurance), and configuration baselines. Partner with thermal engineering on engine cooling, exhaust routing, and heat rejection. Partner with electrical engineering on ECU integration, sensor selection, harnessing, and telemetry. Interface with engine OEMs, fuel system vendors, and propeller manufacturers as the technical lead for propulsion procurement and qualification. Travel to test sites and customer locations to support propulsion test events and field troubleshooting. Perform other duties as directed Required Qualifications Bachelor's degree in Mechanical, Aerospace/Aeronautical Engineering or a related field. 'U.S. Person' as defined by 22 CFR 120.62 required due to ITAR regulations, which includes U.S. citizens, lawful permanent residents (Green Card holders), or protected individuals under asylee or refugee status 7+ years of experience in propulsion engineering small piston engines Deep working knowledge of internal combustion fundamentals: thermodynamic cycles, AFR, combustion, knock, ignition systems, and exhaust Hands-on experience designing and operating engine test stands, including dyno instrumentation, fuel flow measurement, EGT/CHT instrumentation, and data acquisition Experience with EFI Systems Experience with fuel system design across the full flight envelope including: altitude, attitude, and thermal effects on fuel delivery and pressure Experience running structured failure investigations (RCA, FMEA, FMECA or FTA) and translating findings into multi-phase test campaigns Proficiency in Python or MATLAB for engine data reduction, log analysis, and performance modeling Familiarity with propeller selection and matching for fixed-wing platforms Excellent problem-solving skills and attention to detail Strong communication and teamwork skills Ability to work in a fast-paced and dynamic startup environment Preferred Qualifications Experience with Heavy Fuel systems A master’s in similar discipline Experience with sUAS or Group 1-3 unmanned aircraft propulsion Experience with heavy-fuel (JP-5/JP-8) engine integration and qualification Experience reverse-engineering proprietary ECU data formats or building custom log analysis pipelines Background in flight test, including FAA Part 107 or Part 61 operations Who We Are At Firestorm, we are building the future of expeditionary defense manufacturing and autonomous systems. Modern conflict has exposed a fundamental problem: the systems needed most by operators are often too expensive, too slow to produce, and too difficult to sustain at scale. Firestorm exists to change that. We develop mission-adaptable aerial systems and deployable manufacturing infrastructure designed to put capability directly into the hands of the warfighter. From modular unmanned aircraft to xCell - our deployable microfactory - our goal is to make defense systems rapidly deployable, adaptable, and producible at the point of need. We are looking for builders, operators, and problem-solvers who want to work on meaningful technology with real-world impact. Work Environment The position is working onsite in San Diego, CA. at Headquarters We welcome candidates who are local or open to relocating; relocation assistance is available and may be included in the offer package where appropriate. Willingness to travel up to 20% domestically for testing and demonstrations Ability to withstand environmental conditions (e.g., extreme heat or cold, grass, wind, sand, fumes, odors, gases, extreme noise, etc.) This position typically operates in a standard office setting and manufacturing environment. This role requires use of standard office equipment and the physical demands described here are representative of those that must be met to successfully perform the essential functions of the job. Ability to sit, stand, bend, reach and move about regularly throughout the day. Must have manual dexterity to operate standard office equipment. Compensation Base salary: $180,000 - $215,000 base, commensurate with experience Equity: Meaningful equity grant in a growth-stage defense technology company The posted salary range reflects an estimate based on a variety of compensation factors, including but not limited to relevant experience, education, certifications, specialized skills, geographic location, and business needs. Actual compensation may vary, and this range is subject to change as our compensation structure or market conditions evolve. Benefits & Perks Our culture fosters collaboration, respect, and trust, empowering passionate people to do their best work. We offer a competitive salary, comprehensive benefits, and opportunities for career growth. In addition to an opportunity to take part in an innovative, collaborative and fast-growing business with a highly motivated and skilled team, we also take pride in taking care of our employees. Here are just a few ways that we show our appreciation: We offer comprehensive medical, dental, and vision plans 401(k) Retirement Savings Plan to invest in your long-term retirement goals Equity grants for new hires Unlimited PTO Extremely generous company holiday calendar, including holiday hiatuses in July & December. Generous Parental Leave Lifestyle Spending Account FSA DCFSA HSA Hospital Indemnity insurance Critical Illness insurance Accident insurance Basic Life/AD&D, short-term and long-term disability insurance, 100% covered by Firestorm. Plus, the option to purchase additional life insurance for you and your family. Mental Health Resources: We provide free mental health resources 24/7 including therapy and more. Additional work-life services, such as free legal and financial support, are available to you as well. Export Control Compliance To conform to U.S. government export control regulations, including the International Traffic in Arms Regulations (ITAR) and Export Administration Regulations (EAR), you must be a U.S. citizen, lawful permanent resident of the U.S., protected individual as defined by 8 U.S.C. 1324b(a)(3), or otherwise eligible to obtain the required authorizations from the U.S. Department of State or U.S. Department of Commerce. Equal Opportunity Statement Firestorm is an equal opportunity employer, committed to creating a diverse and inclusive workplace, and upholding equitable hiring practices. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, protected veteran status, or any other characteristic under federal, state, or local law, including those with a criminal history, in a manner consistent with the requirements of applicable state and local laws, including the CA Fair Chance Initiative for Hiring Ordinance. We actively encourage members of recognized minorities, women, Veterans, and those with disabilities to apply, and we work to create a welcoming and supportive environment for all applicants throughout the interview process. Firestorm is committed to fostering an inclusive and accessible work environment. If you require accommodations or assistance during the application process, please don't hesitate to reach out to us at View email address on click.appcast.io so we can provide the support you need. #J-18808-Ljbffr