Physical Design Engineer Intern Jobs in Colorado

About the Role

At H3X, we are building the most advanced electric motors in the world for sustainable aviation, marine, industrial, and defense applications. At 12 kW/kg continuous, the HPDM family of integrated motor drives is a step change in electric propulsion technology and removes one of the main barriers blocking widespread proliferation of electric and hybrid aircraft. Our motors range in size from 30 kW to 30 MW, include integrated drives, and are 3X lighter than competitors’ systems.

H3X is looking to hire a mechanical design engineering intern this Fall to support the development across all aspects of the HPDM product line. This is not an ordinary internship- you will be given the full responsibility of a mechanical design engineer. The engineering team is intentionally small and operates at a very fast pace. A high degree of self-motivation and responsibility is required as you will be given significant freedom and will be directly responsible for your parts. We are looking to hire a full time intern with a focus on the Fall 2026 Semester for a minimum of 12 weeks, but open to extended periods as well based on candidate availability.

Responsibilities

• Requirements/Concept

  • Establish and document requirements

  • Conceptualize designs and product architectures that meet program requirements

  • Present in Concept Design Reviews

• Design and Analysis

  • Design parts and assemblies utilizing SolidWorks

  • Perform and document mechanical analyses, including hand calculations, FEA, CFD, etc. for structural, modal, thermal, and/or fluid aspects of products

  • Present in Preliminary and Critical Design Reviews

  • Generate engineering drawings per ASME and GD&T standards, perform tolerance stack-ups

• Prototype and Manufacturing

  • Compile complete Bills of Materials

  • Provide technical supply chain support for sourcing hardware

  • Work with technicians and manufacturing engineers to build initial prototypes

• Testing and Validation

  • Create a Design Validation Plan and Report (DVP&R) for new products and/or subsystems

  • Support testing execution and characterization of new designs

  • Interpret test results, identify root-cause of issues, and make design recommendations to meet the highest level of reliability and performance

• Integration

  • Integrate sub-systems into full systems

  • Support future production builds or complete system tests

• Other

  • Identify workplace hazards and implement safe processes

  • Maintain testing and production equipment where necessary

Required Qualifications

• Pursuing a Bachelor’s or Graduate Degree in Mechanical Engineering or similar

• GPA of 3.0 or higher

• Hands-on experience assembling mechanical systems

• SolidWorks proficient (or similar)

• Excellent written and verbal communication

• Exceptional understanding of fundamentals

• Action biased, results-driven mentality

• Willingness to learn quickly

Preferred Qualifications

• Experience with manufacturing processes (machining, Metal AM, & composites)

• Experience with producing 2D part drawings & GD&T

• Experience with linear structural FEA

Benefits & Compensation

• $23.00 - $37.00 / hr based on school level & experience

• Relocation stipend

• Monthly company events

• Friday Team Lunch

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.