Senior Mechanical Design Engineer Location - Aylesbury Salary - £52,000 £60,000 DOEDuration - Full-time permanent position. Join a growing engineering firm at the forefront of advanced materials and pressure vessel design, supplying systems for some of the world s most demanding environments including defence, aerospace, commercial, and high-end marine sectors. This rare opportunity is perfect for an experienced engineer who thrives in a hands-on, diverse role across design, development, production engineering, and project management. With the company growing at over 35% annually and backed by strong order books, now is the perfect time to make your mark. Why Join Us?Work directly with the Managing Director and lead engineering initiativesInfluence the full product lifecycle: from concept to testing to productionEngage with global partners and government agenciesBe a key part of a tight-knit, high-performing team in a niche, specialist market Your Responsibilities Will Include:Leading the design and testing of pressure vessel assemblies, pneumatic systems, and bespoke equipmentPerforming and approving engineering calculations and technical documentationSupporting production builds and driving efficiency improvementsOverseeing contractor management and supply chain oversightContributing to production planning and capital investment decisions What You Bring: Proven experience in mechanical engineering with exposure to pneumatics, hydraulics or pressure vessels Background in re