Principal Mechanical Design Engineer

Principal Mechanical Engineer
Location: Horsham, West Sussex
Salary: £65,000 – £75,000 DOE

We are seeking an experienced Principal Mechanical Engineer to join a highly skilled engineering team in Horsham. This is a senior technical leadership role offering the opportunity to shape the design, development, and delivery of advanced electro-mechanical systems used in demanding defence applications across land and maritime environments.

This position would suit a mechanically focused engineer who enjoys taking concepts from initial design through to production, leading by example, and working closely with multi-disciplinary teams to deliver high-performance, innovative solutions. You will play a key role in design governance, technical problem-solving, customer engagement, and mentoring engineers while helping to establish best practice across the business.

The role

• Lead mechanical engineering activities from concept through the full design lifecycle.
• Create and develop innovative designs for complex mechanisms and structures using 3D CAD.
• Carry out engineering analysis including stress, fatigue, vibration, and performance assessment.
• Produce and manage detailed engineering and assembly drawings for manufacture.
• Support lab development, testing, verification, and conformance activities.
• Lead engineering reports, technical documentation, and formal design outputs.
• Select materials, coatings, and manufacturing techniques suitable for harsh environments.
• Work closely with wider engineering teams to integrate electronic, control, and drive systems.
• Formulate prototype designs and present the rationale behind design decisions.
• Resolve technical issues and provide effective engineering solutions.
• Lead and support design reviews and release mechanical designs into production.
• Liaise with project managers, sales teams, customers, and suppliers to support successful project delivery.
• Support production, test, and field engineering teams as required.
• Contribute to bids, quotations, proposals, and sales literature.
• Drive continuous improvement through strong collaboration across engineering and manufacturing functions.

The ideal candidate

• Degree educated in Mechanical Engineering.
• Significant experience in the design of complex mechanisms and structures.
• Proven background in delivering designs from concept through to production.
• Strong knowledge of SolidWorks and other relevant modelling tools.
• Confident in performing engineering calculations and analysis.
• Experience working with gear drives, bearings, motors, servo and motion control systems.
• Good understanding of machining, casting, fabrication, and moulding techniques.
• Experience in defence or a related high-specification engineering environment.
• Able to lead and support a small to medium-sized design team.
• Strong communication skills with the ability to present technical information clearly.
• Experienced in coaching, mentoring, and supporting talent development.
• Able to manage priorities, workload, and deadlines effectively.
• Competent in producing risk assessments, safety documentation, and technical support materials.

 

This is an excellent opportunity for a Principal Mechanical Engineer looking to take the lead on complex defence-related design projects and contribute to the delivery of innovative, high-performance engineering solutions.