Senior Mechanical Engineer

What we're building The marine industry supports recreation, global commerce, and national defense. And yet it runs on technology that hasn't meaningfully changed in fifty years. Until now. Arc is on a mission to electrify the marine industry. We're rethinking powertrains, software, and vessel designs from first principles. And we're already executing. We started with consumers to develop and harden our core technology. We're now scaling production of our flagship model with new models and sectors on the horizon. Now we're extending our platform to commercial applications, starting with tugs, ferries, and defense, with years worth of signed contracts and a pipeline that spans every vessel type on the water. The technology is proven, the momentum is building, and the opportunity is enormous. The marine industry is going electric and Arc is building the platform that powers it. Who we're looking for Who We're Looking For As Arc’s Mechanical Engineer, you will own the design and integration of complex electromechanical systems across the full vehicle lifecycle- from early concept and requirements through prototyping, validation, sea trials, and production. This is a full-time, on-site role at our Los Angeles headquarters reporting to our Manager, Mechanical Systems Engineering What you'll do Working across mechanical, electrical, thermal, and manufacturing domains Understanding how assemblies, subsystems, and components interact as part of a larger integrated vehicle. Driving execution across suppliers, shipyards, manufacturing partners, and internal cross-functional teams. Owning the design and integration of complex electromechanical systems across the vehicle lifecycle, from concept through production Driving requirements definition, specifications, CAD design, hands-on prototyping, analysis (FEA, numerical modeling, hand calculations), validation, and production support Designing with manufacturability, serviceability, reliability, and real-world operating conditions in mind Building, testing, troubleshooting, and iterating on hardware in fast-moving development environments Supporting sea trials and in-field validation to verify system performance and resolve real-world issues Working closely with component suppliers, partner shipyards, manufacturing teams, and vessel operators to drive execution Traveling occasionally (~15%) to support testing, validation, suppliers, and field operations Minimum Qualifications 4+ years of experience owning complete mechanical or electromechanical systems from initial design through production Strong fundamentals in structural and thermal engineering Functional knowledge of electrical systems, including high-voltage battery systems and power electronics Experience designing large assemblies or complex multidisciplinary systems Experience with CAD software such as NX, CATIA, or SolidWorks Experience with analysis and modeling tools such as MATLAB, Simulink, or FEA packages Strong intuition for manufacturing methods and design-for-manufacturability principles Practical experience designing, building, debugging, and troubleshooting hardware in production or prototype environments Ability to move quickly and make sound engineering decisions in ambiguous environments Clear written and verbal communication skills Strong time management and prioritization skills Comfortable working hands-on in the field, including on boats and at shipyards Bonus Qualifications Experience working on commercial vessels or marine systems, including familiarity with Coast Guard and ABS regulations Experience with high voltage battery systems Exposure to sheet metal manufacturing, CNC machining, composites, or shop tools Experience with fluid system design including pump sizing, heat exchanger sizing, and hose/pipe routing Experience creating detailed engineering drawings with strong GD&T fundamentals Comfortable pushing at a fast but sustainable pace Enthusiasm for boating, marine systems, and the water At Arc, we enco