A Principal Design Engineer is needed to join GT Wings, one of the UK's most exciting clean shipping technology companies. If your background includes class approved marine structures, structural authority responsibility and hands on stress and fatigue analysis, this is a rare opportunity to define the engineering backbone of world first wind propulsion technology. GT Wings is at a pivotal stage of growth. With its first full scale AirWing installation complete and multiple commercial projects underway, the company is scaling from prototype into repeatable production. Engineering led and purpose driven, GT Wings combines innovation with precision to deliver powerful, class compliant hardware that helps decarbonise global shipping. Joining as Principal Design Engineer, you will take technical ownership of structural integrity across the AirWing system. You will define and evolve structural design philosophy, translate load cases into validated design requirements, and ensure compliance with classification society standards including DNV and LR. This is a hands on technical authority role. You will lead structural analysis activity including FEA and hand calculations, oversee fatigue and buckling assessments, and continuously refine internal analysis capability to reflect real world performance data. You will act as the primary technical interface with classification societies, driving structural approval and ensuring designs meet global marine standards. Working closely with the Head of Engineering and Chief Engineer, you will support system level decisions, review critical design work and help shape the long term product roadmap as GT Wings scales. To qualify: You should be a Principal Engineer, Senior Structural Engineer, Marine Structural Engineer or similar with a CV that demonstrates: Degree in Naval, Mechanical, Structural or Marine Engineering Strong experience delivering marine structures approved by classification societies Proven ability to translate load cases into robust, validated structural designs Significant experience in structural analysis including FEA and hand calculations Experience engaging directly with classification societies and driving technical approval Confidence operating as a technical authority within complex hardware programmes Practical engineering judgement and accountability in fast moving environments Proficiency in Siemens NX, Autodesk Inventor or equivalent 3D CAD, experience with fatigue and large welded structures, aero structural systems, structural testing and validation or Design for Manufacture principles would be advantageous. In return, you will join an ambitious start-up at a defining stage of growth, working on leading edge maritime hardware with genuine technical ownership. Expect a competitive salary (£65-£75k DOE), hybrid flexibility with three days onsite in Southampton, private healthcare and the opportunity to shape the structural credibility of a globally scalable clean technology.