Subject Matter Expert

NATS Ltd; United Kingdom; Hybrid; GBP 45,000 - 75,000; Full time

Benefits offered by this job

Flexible working arrangements

Hybrid/remote work option

Opportunities for professional growth

Job summary

NATS Ltd is seeking a technically skilled professional to act as a domain expert for one or more systems, supporting assurance, documentation, and in-service changes. You will work closely with Domain Leadership and project teams to maintain system integrity and regulatory compliance.

The role offers agile working with a mix of office and remote work, and requires security vetting for UK eligibility. A strong background in systems engineering and the SFIA framework will be advantageous.

Qualifications

• Minimum HNC in Engineering or IT or equivalent with structured technical training.
• Experience in safety-critical or real-time environments desirable.
• Strong understanding of system engineering lifecycle and standards.

Responsibilities

• Serve as primary technical expert for assigned system(s) and support operational assurance.
• Maintain and update system documentation, SRAs, SADs and technical files.
• Contribute to change and transformation projects with Domain Leadership.
• Engage with stakeholders and external regulators as needed.

Skills

Systems engineering

Technical support

Problem solving

Communication

SFIA Systems Design Level 3

Education

Higher National Certificate in Engineering or IT

Job description

NATS is the UK’s leading air navigation service provider, handling over 2.4 million flights each year. We provide air traffic control services from two control centres and at airports around the UK. We also provide a wide range of commercial products and solutions internationally. Our people are at the heart of our purpose to advance aviation and keep the skies safe.

Closing Date: 21/09/2026

Job Purpose/Overview

Act as a technical expert for a specific system or group of areas (systems, domains, capabilities, assets or services). Provide subject matter expertise to support the assurance, sustainment, and evolution of in-service areas. Contribute to the maintenance of system documentation, regulatory compliance, and support transformation and change activities as required. Operate under the guidance of the Domain Leadership, with responsibilities agreed on a system-by-system basis.

Other Duties Include

• System Expertise & Support: Serve as one of the primary technical experts for assigned system(s), supporting operational assurance and system understanding across the Domain.
• In-Service Asset Assurance: Maintain and update key system documentation including but not limited to Work Instructions, Security Risk Assessments (SRAs), System Architecture Documents (SADs), and Technical Files. This also includes maintenance of Operational Support environments as needed.
• Regulatory & Safety Documentation: Support the upkeep of regulatory documentation and safety assurance artefacts to ensure continued compliance.
• Problem & Change Support: Contribute to the analysis and resolution of PTRs (Problem Tracking Reports) liaising with operational units and support the definition and implementation of changes to in-service systems.
• Transformation & Change Projects: Provide system-specific input to transformation initiatives and asset change projects, as requested by the Domain Leadership.
• Collaboration & Communication: Work closely with the Domain Leadership, Project Managers, Engineering Leads, and other SMEs to ensure consistent and informed decision-making.
• Continuous Improvement: Stay informed of industry trends, technology developments, and operational feedback to identify opportunities for system improvement.

Autonomy

Operates with autonomy in system-specific matters under the direction of the Domain Leadership. Responsible for delivering agreed outputs and maintaining system documentation and assurance artefacts. Escalates decisions outside of agreed scope, all within the boundaries of NATS Business Management processes (BMS).

Job Scope

• System Support: Acts as the internal expert for one or more systems, ensuring continuity of knowledge and technical integrity.
• Documentation & Assurance: Maintains system documentation and supports assurance processes, including updates to safety and regulatory artefacts on behalf of Domain Leadership.
• Support to Projects: Provides input to change and transformation projects, ensuring system-specific considerations are addressed.
• Stakeholder Engagement: Interfaces with internal stakeholders and, where appropriate, external suppliers or regulators on system-specific issues.
• Technical Expertise: Provide technical input throughout project phases, providing efficient resolution of issues to stakeholders.
• Design Envelope Evolution: Assist in defining and refining the design envelopes for in-service systems, ensuring alignment with operational needs and future capability.

Essential Skills and Experience

• Qualifications: The post holder is expected to hold, as a minimum, a Higher National Certificate in an Engineering or Information Technology related discipline, and relevant experience. Job holders not holding the expected qualification but who have undertaken structured technical training (e.g. apprenticeship recognised by a professional body) with recognised qualification ideally to at least HNC equivalent level will also be considered.
• Experience: Experience in systems engineering or technical support roles, ideally within safety-critical or real-time environments. Familiarity with the assigned system(s) is highly desirable.
• Knowledge: Strong understanding of the assigned system(s) and their operational context. Familiarity with relevant technical standards and assurance processes.
• Skills: Strong problem-solving ability, understanding of the systems engineering lifecycle, effective communication skills, and attention to detail with a commitment to quality. Expected to align with skills from SFIA Systems Design Level 3.

Additional Vacancy Information

We have adopted agile working to provide greater flexibility and increased choice over working arrangements, with the opportunity for this role to work in our modern office facilities as well as remotely. We also welcome discussions on flexible and part-time working arrangements.Find out morehere .

Please note:All staff at NATS are subject to UK Security Vetting and Clearance (SC) and mustmaintainvalid clearance throughout employment. We are unable to progress applications where an applicant does not meet eligibility requirements for clearance. For further guidance, please click here - Security Clearance - NATS.

If you share our passion to advance aviation and keep the skies safe – we would like to hear from you whatever your age, sex, race, faith, sexual orientation, gender identity, gender expression, visible or invisible disability. Individuals that bring different perspectives, skills, lifeexperiencesand backgrounds help us be at the forefront of our industry.