16 senior principal mechanical engineer jobs found

Principal Mechanical Engineer – Water Leading Engineering Consultancy | Water Sector | Hybrid Working | Long-term Contract | Outside IR35 | Competitive Rate The Opportunity We're recruiting a Principal Mechanical Engineer to deliver high-quality mechanical engineering design and technical leadership across multiple water sector projects. You'll be responsible for leading mechanical engineering workstreams, ensuring compliance with sector standards, managing design delivery, and mentoring engineering teams. Contract Details: Outside IR35 | Competitive daily/monthly rate | Hybrid working| Long-term contract MUST HAVE: Current water sector experience. This is a senior technical role for an SQEP (Suitably Qualified Experienced Person) mechanical engineer with proven, recent expertise in water, wastewater or biosolids treatment. You'll have the capability to lead mechanical engineering on projects or groups of projects, managing design quality, timescales, cost and compliance....

Job title: Senior Mechanical Engineer (Building Services) Location: Cardiff / Swansea (Hybrid 3 days per week) Pay Rate: £51 per hour Umbrella PAYE (37.5 hours per week) Qualifications required: Degree / IEng / CEng Travelling costs expensed Notice Period: 4 weeks Contract Term:4 months (with extension) About the company Our client are ranked as one of LinkedIn's Top 25 Companies, where UK professionals want to work and stay once they join. They've also made the Times Top 50 employers for women. Their Infrastructure team uses innovation, new approaches and the power of data to help our clients deliver end-to-end projects and programmes for essential future infrastructure. And as the work becomes ever more complex, their employees continue to challenge the status quo. Our client are looking for Senior / Principal Mechanical Building Services Contract Engineer to join their growing team in Cardiff. The responsibilities of the role are: Client briefing and stakeholder...

Job Title: Senior Mechanical Servies Engineer Rate: £73 per hour via Umbrella (Inside IR35) Location: Devonport Contract Length: 12 Months Role purpose The primary purpose of this role is to lead and assure delivery of multi?disciplinary dockside design work to the required safety, quality, schedule and cost. Operating with a high level of autonomy, the postholder will own one or more work packages end?to?end, set technical direction, plan and control delivery, manage multi?disciplinary interfaces, and review/check fit?for?purpose design documentation and technical deliverables. The Senior Engineer will act as a key interface to the Design Manager and Principal Mechanical Engineer (Mechanical Services Lead), providing technical leadership, risk ownership, supplier oversight, and mentoring to engineers and designers. Key Responsibilities Own/manage the technical baseline and requirements for assigned packages; act as Responsible Engineer and technical focal point from need...

BAE Systems is seeking an experienced Senior Mechanical Engineer (HVAC) to lead the design, integration and technical assurance of HVAC systems on complex marine platforms. Reporting to the Principal Engineer - HVAC, you'll play a key role across the shipbuilding lifecycle, delivering robust, compliant and customer‑focused engineering solutions. You'll be responsible for developing HVAC designs and specifications, carrying out technical analyses (including heat loads, psychrometrics, pressure loss and noise calculations), and providing expert input to investigations, reviews and supplier engagement. You will also mentor engineers within the team and help drive continuous improvement in engineering processes and standards. About you: Strong experience in marine or building services HVAC system design Experience in Stage 1 design Degree qualified in engineering (or equivalent experience) Background in defence, maritime or complex engineering environments Confident producing...

Principal Mechanical Engineer Location: Remote (occasional travel to local office: London, Manchester, Newcastle, Glasgow) 6 Month rolling contract £65 per hour Umbrella - Inside IR35 only Overview ARM is recruiting for an experienced Mechanical Engineer to support a growing Energy Transition team delivering some of the UK's most innovative low- and zero-carbon energy projects. The Role As a senior member of the engineering team, you will lead mechanical engineering activities from early-stage feasibility studies through to detailed design, construction support, operation and decommissioning. You will work closely with developers, utilities, EPC contractors, OEMs, government bodies and investors to deliver safe, practical and commercially effective engineering solutions. Key Responsibilities Develop innovative and cost-effective mechanical engineering solutions Lead mechanical design activities across Feasibility, Concept, FEED and Detailed Design stages Produce...

Job Title: Principal Civil Engineer Role Overview The Principal Civil Engineer provides technical leadership and oversight for the design, delivery, and assurance of civil engineering works on railway infrastructure projects. This role is responsible for ensuring that all civil designs and construction activities meet regulatory requirements, safety standards, and project objectives, while driving innovation, efficiency, and best practice across the engineering lifecycle. Key Responsibilities Technical Leadership Lead the development and delivery of civil engineering designs for rail infrastructure, including track, earthworks, drainage, structures, and station works. Act as the technical authority for civil engineering within the project, ensuring robust and compliant design solutions. Review, approve, and sign off on design packages, calculations, and technical reports. Provide guidance and mentorship to engineers and design teams. Design Management & Coordination...

Role: Project Controls Manager Position: Contract Location: Based in our London or Suffolk office with hybrid working available - Travel to Paris will also be required Days on Site: 3 (TBC) Duration: Ongoing, Initial CED 31/12/2026, rolling contract thereafter Pay: up to 650£ PAYE/ 940 £Umbrella Vacancy Overview: Are you looking for a career which is rewarding, at the cutting edge of project development and where you can really make a difference? Come and join our expanding Sizewell C (SZC) team and work on one of the most exciting and largest megaprojects in the UK, whilst being at the forefront of the UK's climate change agenda and energy policy. Following on from the success of Hinkley Point C (HPC), the SZC Project is a nuclear new build project in Suffolk, which has obtained planning approval and Government financing support. The project has started construction and is now seeking private investment. When completed, it will provide dependable electricity to 6 million...

Our client, a leading organisation in the Defence & Security sector, is currently seeking a Principal Thermal Mechanical Engineer on a contract basis to join their team in Cowes. This role involves working on the design, integration, and testing of complex mechanical systems within maritime services. Key Responsibilities: Design and implementation of thermal management systems, including heat exchangers Conduct Computational Fluid Dynamics and Finite Element Analysis Oversee the design, build, test, and deployment of composite structural materials Serve as the Mechanical Design Authority for Future Radar Products Ensure compliance with relevant Standards and apply them effectively Engage in all engineering lifecycle phases, from requirements capture to in-service support Provide subject matter expertise in Thermal Mechanical Systems and related mechanical domains Collaborate with multidisciplinary teams to achieve project objectives Job Requirements: Experience in the...

Senior Civil Engineer (Chartered) Location: Birmingham Office Contract: 6 Months (ASAP Start) Engagement: Outside IR35 Sector: Transmission MRR Infrastructure is recruiting for a Chartered Senior Civil Engineer to join a highly respected engineering organisation delivering major UK transmission infrastructure projects. This is a six-month contract opportunity, confirmed as outside IR35, based within the Birmingham office. The Opportunity You will operate in a senior technical capacity within the Civil and Structural team, leading design activities across high-voltage transmission projects from concept through to detailed design and construction support. This role is suited to an experienced Chartered Civil Engineer who is confident leading design packages, mentoring engineers, managing client interfaces and delivering complex infrastructure solutions within regulated environments. The Organisation Our client is a globally established, employee-owned engineering and...

Principal EC&I Engineer - Nuclear Infrastructure Location: Glasgow (Hybrid - ideally 2 days per week on site) Contract: 12‑month contract Security Clearance: ability to obtain SC clearance We are supporting a major UK nuclear infrastructure programme in the appointment of a Principal EC&I Engineer to act as Electrical Lead. This is a senior, hands‑on leadership role, responsible for the delivery of nuclear safety‑implicated EC&I design across new infrastructure works within a highly regulated environment. Key Responsibilities Act as Electrical Lead for scheme design on nuclear safety‑implicated infrastructure. Lead and coordinate EC&I design activities including: HV and LV power systems Traditional building services electrical design Specialist communications and control systems Provide day‑to‑day leadership for a team of 5-6 electrical engineers, ensuring alignment with programme milestones. Ensure the team is working on the right activities at the right...

A well-established client of ours are looking for a Project Manager for the delivery of essential infrastructure projects across electricity transmission, distribution, renewable energy and customer connection frameworks, with an emphasis on a National Grid substation in the Wiltshire area. This assignment will start 13/04/2026 and last 6 months. This would be an inside IR35 role. Key responsibilities: Lead multidisciplinary construction and engineering teams through end‑to‑end project delivery, ensuring alignment across civil, M&E, and commercial workstreams. Deliver projects to agreed time, cost, quality, and safety requirements. Drive a cohesive project team ethos across Construction Managers, Commercial Managers, Design Leads, and Project Engineers Provide strong safety leadership, including preparation and oversight of Health & Safety Plans, Method Statements, and Risk Assessments. Maintain the highest standards of HSEQ performance and ensure compliance with...

Role: Planning Engineer / Wrapping, Insulation and Caulkin Planner Position: Contract Location: Hinkley Point C Days on Site: 3 Duration: Approx until 31st Dec 2026 Pay: Inside IR 35, Up to 429 PAYE - £468.92 umbrella Job Purpose / Overview The Wrapping, Insulation and Caulking (WIC) planner is a key role within the Integrated Planning team which encompasses Design, Engineering, Procurement, Manufacturing, Logistics and Installation for the WIC Scope of Work for HPC.The Planning Teams work within a matrix organisation supporting all the involved areas, programmes & contracts of Works across Unit 1 & Unit 2 Nuclear Island (NI), Conventional Island & Balance of Plant and the Offshore Marine Scope (CI/BOP) .The WIC Planner is accountable to the MEH Lead Planner for WIC planning throughout the project lifecycle, it's Productivity,the quality of its outputs their accuracy and value, the implementation of the broader HPC Planning Strategy, the provision ofa...

Senior / Principal CE&I Design Engineer - Silos MSSS SEP1&2 Sellafield Site (3 days/week on plant) | West Cumbria Design Office | Monthly Warrington visit Up to £80/hour (Inside IR35) | SC Clearance required | An opportunity has arisen for a Senior or Principal CE&I Design Engineer to join the Silos MSSS SEP1&2 CE&I design team, supporting one of the UK's most complex and safety-critical nuclear environments at Sellafield. This role is central to providing front-line, site-based design support to Commissioning teams, ensuring that detailed CE&I designs and changes are delivered, reviewed, and verified to meet stringent functional and business requirements. You will play a key role in shaping safe, compliant, and buildable engineering solutions-while delivery and commissioning execution is handled by dedicated site teams. Key Responsibilities Provide site-based CE&I design support to commissioning activities on MSSS plant (SEP1 & SEP2) Deliver...

Contract Opportunity - Principal CE&I Engineer (Inside IR35) Location: Hybrid - 8 days in Warrington Office £60-68 Inside IR35 The Role We are seeking an experienced Principal Electrical, Control & Instrumentation (CE&I) Engineer to lead the electrical systems design for the SIXEP Cooling Towers and other local projects. This is a key technical leadership role, responsible for driving CE&I design delivery from concept and preliminary design through to detailed design, installation and commissioning support. You'll play a pivotal role within a small, integrated design team, providing technical leadership, assurance, and hands-on expertise across all aspects of CE&I engineering. Key Responsibilities Lead and take full responsibility for CE&I design delivery across assigned projects Produce, review and check engineering deliverables through all design phases Provide technical support during installation and commissioning, addressing design queries as...

Control Systems Engineer - Energy Sector Location: Remote with occasional travel to either Manchester, London, Newcastle & Glasgow (depending on your location) Contract: 6-Month Rolling Contract Rate: Up to £65ph Umbrella IR35: Inside IR35 ARM is recruiting for an experienced Control Systems Engineer to support major projects across the power generation, utilities, oil & gas, and process industries sectors. Key Responsibilities Develop Control Narratives, Control Philosophy, and Functional Logic Specifications Support DCS configuration, FAT/SAT, commissioning, and system optimisation Design industrial control system architectures and communication networks Work with OEMs, EPC contractors, and multidisciplinary engineering teams Support control system upgrades, migrations, and cybersecurity compliance activities Required Experience Strong C&I/control systems background within energy or process industries Experience on FEED or Detailed Design projects with major...

Principle Electrical Engineer - Low Carbon Remote (Remote with occasional visits to the office for project meetings) Up to £65 per hour (Umbrella) Overview: You'll be part of a multidisciplinary team delivering cost-effective, efficient and innovative engineering solutions to complex challenges, helping to shape practical, high-quality designs across a wide range of energy projects. This role involves contributing to projects at all stages of maturity, including Feasibility Studies, Concept Design, FEED, Value Engineering and Detailed Design. You'll take a lead role in developing electrical engineering deliverables and supporting the assessment, optimisation and safe operation of electrical systems across the energy sector. Key Responsibilities: Lead and support the development of practical, cost-effective and innovative engineering solutions in collaboration with wider project teams. Deliver engineering work across multiple project phases, from early-stage feasibility...