Principal Mechanical Engineer

About Epirus Epirus is a high-growth technology company that develops solid-state, human-safe directed energy systems that enable unprecedented counter-electronics effects and power management solutions to enhance power efficiency in defense and commercial electronics. With a constant emphasis on innovation, we are redefining modern power systems to increase the velocity of change for our customers and bring tomorrow's capabilities to life, today. Job Summary: In this role, you will be responsible for mechanical architecture definition of a new generation of Epirus systems, including development of new technology to optimize system design and maximize system performance. The ideal candidate has experience designing, building, and testing radio frequency (RF) electronic packages, electromechanical assemblies, and large dynamic structures. This engineer will be expected to take designs from initial concept through design, analysis, prototyping, and production. This role requires a high level of ownership and collaboration with EE, RF, systems, and supply chain disciplines. Responsibilities:  Design and build electronics enclosures, mechanisms, and mounting structures for RF phased arrays accounting for environmental requirements and mechanical longevity. Translate complex system objectives into clear mechanical requirements, including bounding load cases, weight budgets, and interface diagrams. Collaborate with engineering teams to ensure structures meet environmental and mission-specific requirements for shock, vibration, and dynamic loading. Support redesign and optimization initiatives for high-performance mechanical systems. Work closely with electrical, RF, systems, and manufacturing engineering teams to develop innovative and robust designs. Ensure all mechanical solutions align with broader system-level requirements and constraints. Present detailed design solutions at both internal and external reviews and act as a subject matter expert in mechanical design evaluations. Contribute to continuous improvement of design practices and standards. Lead mechanical design teams and provide mentorship to junior engineers, fostering a culture of technical excellence and continuous learning. Perform thermal and structural analyses to support design verification and environmental qualification. Create detailed CAD models and manufacturing drawings with proper tolerance analysis and GD&T in compliance with ASME Y14.5 Interface with supply chain teams, external vendors, and internal manufacturing to ensure high-quality, manufacturable designs that meet cost and schedule objectives. Design complex interconnect solutions, including harnesses and cable assemblies for large-scale integrated electronic systems. Develop and automate custom tools to accelerate product development and enhance design speed, accuracy, and efficiency. Basic Qualifications: BS degree in Mechanical, Aerospace, Structural or similar engineering field.  8+ years of experience in mechanical design and analysis, including design ownership across a full product lifecycle. Expert proficiency in mechanical design packages such as SolidWorks or equivalent and practical application of GD&T. Strong understanding of engineering fundamentals in structures, thermodynamics, and mechanisms. Comfortable with basic Finite Element Analysis and structural and thermal hand calculations.  Demonstrated ability to assemble prototypes and first-article builds, including test, troubleshooting and minor fabrication. Ability to understand and contribute to electrical schematics, diagrams and interconnects Strong written and oral communication skills Desired Qualifications: MS degree in Mechanical, Aerospace, Structural, or similar engineering field.  Experience with kinematic synthesis, electric actuation, mechatronics, and instrumentation. Experience analyzing and/or testing systems under static loading, shock, and vibrational environments including random vibration.  Effective communication skills with a collaborative, team-first mindset and the desire to improve scalability of workflows and processes Comfortable and organized while working in a fast-paced, ever-changing environment  Experience with phased array design and/or analysis  ITAR REQUIREMENTS:  To conform to U.S. Government space technology export regulations, including the International Traffic in Arms Regulations (ITAR) 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 eligible to obtain the required authorizations from the U.S. Department of State. Learn more about the ITAR here.  As required by the Equal Pay Transparency Act, Epirus provides a reasonable range of minimum compensation for roles that may be hired. Actual compensation is influenced by a wide array of factors including but not limited to skill set, level of experience, and specific office location. For the state of California only, the range of starting pay for this role is: $138,000—$193,000 USD