Senior or Principal Mechanical Engineers - Defence - Attractive Northern England (Cumbria) - Permanent and Long Term - Military and Defence SystemsMultiple Senior or Principal Mechanical Engineers are required for an international Defence and Weapons Systems Company that is expanding their team.Salary and Seniority will depend on your skills and experience.This position will require full-time on-site presence (4.5 Day and 37 Hours - Plus Paid Overtime is Actively EncouragedThe Senior or Principal Mechanical Engineers will be part of the Mechanical Engineering team and will be involved in supporting technical changes to existing company products (i.e Defence and Weapons Systems).This role may suit candidates from the Oil and Gas Industry or another Safety Critical Engineering sector.The Senior or Principal Mechanical Engineers will be involved in the Mechanical Development, Tests, Trials and Commissioning and will have the opportunity to shape the next generation of defence/weapons platforms and future technology.Key Duties and Responsibilities for the Senior or Principal Mechanical Engineers Developing the package of design evidence required to justify a safe, effective design and generate customer confidence in the design solution.Specifying and assisting in the build of prototypes, products and systems suitable for testing.Providing timely corrective actions on all assigned defects and issues.Ensuring that commitments are agreed, reviewed and met.Mentoring junior engineers