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Reliability Engineer

H3X Technologies

H3X Technologies

Software Engineering
Louisville, CO, USA
USD 125k-200k / year + Equity
Posted on Oct 4, 2025

Location

Louisville, Colorado

Employment Type

Full time

Location Type

On-site

Department

Engineering

About the Role

H3X manufactures the world’s most power-dense electric motors for aerospace, defense, marine, and heavy industry. Our motors have integrated drives, range in size from 30kW to 30MW, and are 3X lighter than competitors.

We’re a fast-moving, first-principles hardware startup; you’ll own reliability end-to-end—from physics-of-failure modeling to instrumented testing on dynos and in environmental chambers—so our products thrive in demanding high-temperature, high-vibration, high-voltage, and high-altitude environments.

As the first Reliability Engineer on the H3X team, you will establish internal Design-for-Reliability (DfR) guidelines and prove out MTBF/availability targets for our integrated motor drives and subsystems: motors, inverters, and gearboxes. You’ll translate product requirements and customer mission profiles into accelerated life tests and certification-ready evidence across electronics and rotating machinery. You’ll also help architect redundancy and common-cause mitigations for our multi-inverter, multi-winding topologies.

Responsibilities

  • Own system reliability modeling for IMDs and subsystems using FMEA/FMECA, FTA, reliability block diagrams, and Weibull analysis; roll up component hazard rates to system MTBF (series/parallel math, common-cause factors, etc).

  • Identify critical reliability bottlenecks across H3X’s products to inform design changes in future product block upgrades

  • Plan and support execution of reliability test campaigns that map clearly to critical wear-out mechanisms:

    • Electronics: HTOL/thermal cycling & shock (Coffin-Manson/Engelmaier), power/temperature derating per IPC-9592, solder joint reliability per IPC-9701.

    • Vibration (and other environments): random vibration/durability using inverse-power-law models and DO-160 vibration/environmental categories where applicable

    • Rotating hardware: bearing life (L10/ISO 281 with lubrication/contamination factors) and seal wear

    • High voltage insulation: thermochemical and thermomechanical degradation of stator winding and power MOSFET insulation systems, including impacts of partial discharge

  • Quantify acceleration factors using physics-based models (Arrhenius for thermal/chemical, inverse-power-law for vibration/mechanical; humidity via Peck/Hallberg-Peck when needed)

  • Define pass/fail and success criteria that demonstrate system MTBF/availability goals with high confidence and statistical significance, and justify test equivalency between accelerated stresses and field conditions.

  • Instrument and analyze to perform root-cause analyses on test article failures.

  • Partner across disciplines (motor design, power electronics, firmware, manufacturing) to drive design changes, derating, screening (HALT/HASS when appropriate), and supplier quality actions.

  • Author clear technical reports and customer-facing evidence packages (methods, results, confidence bounds, traceability to requirements).

Required Qualifications

  • 5–10+ years in reliability engineering for high-performance electromechanical systems (aero/auto/defense, power electronics and/or electric machines).

  • Demonstrated FMEA/FMECA leadership and system-level reliability roll-ups across electronics + rotating machinery.

  • Hands-on design and analysis of accelerated life testing with physics-of-failure models:

  • Thermal: Arrhenius/HTOL, thermal cycling (Coffin-Manson/Engelmaier).

  • Mechanical/Vibration: inverse-power-law models and durability testing.

  • Altitude/HV: partial discharge and creepage/clearance at reduced pressure (Paschen).

  • Fluency with relevant standards such as IPC-9592, IPC-9701, MIL-HDBK-217F, AEC-Q100, and DO-160G; working knowledge of IPC-2221B.

  • Strong data analysis skillset using Python, MATLAB, or ReliaSoft/HBK; clear technical writing.

  • Comfortable building fixtures, running chambers & shakers, and spending time in the lab.

Preferred Qualifications

  • Experience integrating safety & certification alignment with systems engineering—e.g., provide reliability inputs to ARP4754A/ARP4761A safety assessments and environmental qualification plans aligned to DO-160G for airborne use cases

  • Experience with fault-tolerant architectures (redundant inverters/windings) and modeling common-cause failures and latent-defect screening.

  • Aerospace safety & certification exposure (ARP4754A/ARP4761A, safety assessments, requirements traceability)

  • Familiarity with high-voltage PCB design at altitude (IPC-2221B creepage/clearance)

  • Prior work qualifying to DO-160 temperature/altitude, vibration, EMI/lightning categories for airborne equipment.

Benefits & Compensation

  • Salary: $125,000 - $200,000 based on level

  • Employee equity incentive plan

  • Health insurance: medical, vision, dental, ST & LT disability, and life

  • Gym membership stipend (up to $60/month)

  • Epic or IKON Ski/Snowboard Pass (up to $869 provided)

  • Flexible hours (deliverable-based goals)

  • Flexible time off (just need manager approval) or PTO Policy (80 hours per 2000 hours, accrued per hour, PTO can be taken by the hour)

  • Relocation package

  • Bi-weekly company events

  • 401k program

The Company

H3X Technologies is a U.S.-based manufacturer of electric motors for sustainable aviation, marine, industrial, and defense applications. They have developed a family of integrated motor drives that can scale in power from 30kW to 30MW with power densities as high as 12 kW/kg and best-in-class efficiency. This high performance is enabled by novel scalable core technology and proprietary manufacturing processes for motor stacking, winding, and assembly. The design, manufacturing, and testing of their products is done in-house at their headquarters in Louisville, Colorado.

H3X’s world-class team is composed of experts from Tesla, SpaceX, GE Aviation, and Siemens with deep knowledge in electric machines, power electronics, material science, control systems, and advanced manufacturing. They take pride in our multidisciplinary approach, relentless dedication, high capital efficiency, and Skunkworks-style execution.

H3X has raised over $30M and has backing from top VC firms and strategic firms including Lockheed Martin, Hanwha, Y Combinator, Cubit Capital, Metaplanet, TechNexus, and Liquid 2 Ventures to deploy capital for rapid scaleup.

H3X is poised to become the world’s leading supplier of advanced electric motors by 2030 to drive deep decarbonization in aviation, marine, and heavy industrial applications and unlock next-generation electrified defense technology to strengthen national security.

H3X is an equal opportunity-affirmative action employer and considers all qualified applicants for employment based on business needs, job requirements and individual qualifications, without regard to race, color, religion, sex, age, disability, sexual orientation, gender identity or expression, marital status, past or present military service or any other status protected by the laws or regulations in the locations where we operate.