Principal Mechanical Design Engineer

Company Ultra Intelligence you will make critical engineering decisions to deliver high‑quality design outputs. In this role, you will also serve as a technical anchor, mentoring junior engineers and continuously driving engineering excellence across the team. Key Responsibilities Define and manage mechanical design requirements, ensuring validation and verification. Responsible for developing, documenting and delivering robust mechanical solutions for complex systems using the 3D CAD system and the company engineering toolsets. Lead mechanical integration, verification, and acceptance testing, collecting and presenting evidence as required. Create and peer review technical artefacts, including mechanical design documentation, design data packs, analysis reports, plans and procedures in accordance with our product development framework. Define, analyse and document predicted mechanical functional behaviours and performance. Optimize the design of parts based on various manufacturing technologies: machined from solid, injection moulding, extrusion, sheet metal and casting. Perform tolerance analysis of close tolerance parts and complex assemblies. Produce mechanical designs for complex systems that meet defence standards MIL-STD and DEF-STAN, EMC and TEMPEST requirements and harsh environmental conditions. Create and review high‑quality drawings to BS8888 standard to guarantee design precision. Select optimum engineering materials and finishes to suit cost and performance. Identify and integrate Commercial Off‑The‑Shelf (COTS) mechanical hardware, ensuring compliance with design specifications, rationalising cost, lead time and long‑term component availability. Design production jigs and fixtures in conjunction with production engineers. 3D Print and scan components; and produce rapid prototypes. Hold and contribute to peer design reviews ensuring adherence to design processes. Dynamically prioritize daily tasks and cross‑functional workstreams, ensuring tight project deadlines are consistently met under high‑pressure constraints. Conduct rigorous design reviews of mechanical drawings, ensuring precise application of Geometric Dimensioning and Tolerancing (GD and the ability to communicate effectively at all levels. Demonstrate a helpful 'can do' attitude. Desired Skills, Qualification and Experience Experience of Mechanical Integration, Verification and Validation activities. Skilled in writing mechanical requirements based on systems requirements using proprietary software. Knowledge of hazardous materials, ROHS and REACH restrictions. Possess UK driving license. Security Clearance Candidates must be willing and able to obtain, and maintain, DV security clearance. Notice Due to the nature of the programs we deliver for our customers, candidates may need to obtain the relevant security clearance or handle export‑controlled material as defined by the role's requirements. Applicants must be able to obtain and maintain the appropriate level of security clearance for the role. Due to the nature of our work, you must be a British Citizen who has been resident in the UK for the past 5 years in order to apply for SC clearance and 10 years for DV. For more information, please visit the UKSV website. Our Benefits Participation in an Annual Bonus Scheme Private Medical Cover 25 days’ holiday (plus Bank Holidays) with the option to buy an extra 5 days Pension Contribution 4 x Life Assurance Cover Flexible working hours with opportunity for a 1pm finish on a Friday Flexible benefits including cycle to work scheme, will writing and more Security Clearance Allowance – where relevant and subject to you holding the required security clearance Diversity, Equity