Principal Systems Engineer

Job Title: Principal Systems Engineer

Location: Portsmouth Naval Base – On site

Salary: Up to £58,000 depending on skills and experience + 10% bonus

Who we are:

Join BAE Systems and you’ll be part of something bigger. As a valued member of our global colleague network, you’ll bring your unique skills and perspectives to help pioneer progress and protect what matters most. You’ll be trusted to play your part in delivering the advanced, technology-led defence, aerospace and security solutions of tomorrow, shaping a safer future, for all of us.

From the depths of the ocean, to the far reaches of space, there’s no limit to where a career at BAE Systems could take you.

What you’ll be doing:

In this position you will be applying Systems Thinking to understand the wider problem space, manage constraints and emergent behaviours, and balance key trade‑offs while shaping Architecture & Interfaces that define how systems work and interact. You will deliver strong Requirements Leadership and Management by capturing, decomposing and agreeing requirements, maintaining traceability and managing change. The role will champion Model‑Based Systems Engineering (MBSE) by modelling system behaviour, structure and interfaces, ensuring modelling standards are followed, and generating controlled outputs that support design, verification and validation. In addition, you will also apply Problem Decomposition & Complexity Management to break down multi‑domain challenges, visualise dependencies and maintain structured decision records throughout delivery.

You will contribute to Lifecycle Delivery & Systems Integration by tailoring lifecycle processes, planning integration when required, and preparing for design and test reviews. Service Hub Collaboration will be a requirement, involving close engagement with Asset Management Service Hubs to tailor and deliver systems engineering capabilities and services. Through strong Technical Expertise & Leadership, you will lead reviews, manage risks and issues, ensure governance and safety expectations are met, and deliver work packages to cost, schedule and quality. You will also mentor and coach engineers, promote systems engineering best practices and exemplify BAE Systems behaviours and ways of working.

Essential skills:

• You’ll have strong experience of applying systems engineering across the lifecycle, including requirements management, architecture definition, integration, MBSE and V&V
• You’ll have experience of using high level design methodologies and architectures (e.g. UAF, NAF, TOGAF, SysML, UML) and practical capability in MBSE, using tools such as Enterprise Architect to model system behaviour, structure and interfaces. Additionally, you will have experience using requirements and interface management toolsets (e.g., DOORS), maintaining traceability and controlling system interfaces
• You’ll have knowledge of applying Systems Engineering standards and principles including ISO 15288
• You’ll have exposure to system integration and verification activities to ensure functional and performance needs are met
• You will be Degree level qualified (or have equivalent experience) in a STEM or systems related discipline, with desirable awareness of maritime or ship systems. You must be working towards CEng or operating at that level of capability

The BAE Systems Warship Technical Authority Hub:

This position sits within the Systems Engineering Hub, which is part of the Warship Technical Authority (WTA) Service Hub. The WTA aims to deliver Naval whole ship, systems and equipment engineering support and change management.

The position will be part of a high performing Systems Engineering team, which works across the Maritime and Land Defence Solutions business unit. They will be required to lead and manage the delivery of on-going contracted workstreams and deliver tailored systems engineering services to the Asset Management Service Hubs, which comprises of warship Platform Management, Maintenance Management, Supply Chain, Data and Digital Services.

The Principal Systems Engineer provides technical leadership, acts as a technical authority within their scope, engages with customers and suppliers, and mentors engineers to build capability across projects and teams.

As a Principal Systems Engineer you will support the delivery of one or more of the core WTA service elements; Design Change Management, Platform Technical Assurance, Material State Management, Obsolescence Management, Specialist Engineering Support, Future Support and Transformation Planning.

Why BAE Systems?

Here you’ll build a career with purpose and limitless possibilities. With lifelong learning and meaningful work, this is a place where you can grow your career with confidence and be empowered to be your best. You’ll be recognised for your contribution and enjoy rewards tailored to what’s most important to you and your family, support for your financial and personal wellbeing, as well as a balanced lifestyle. In an environment embracing sustainable ways of working and with a strong sense of shared purpose, our supportive culture is a place you can feel you belong and proud of the difference you make.

A place where everyone can thrive:

We’re committed to building an inclusive workplace where everyone feels valued and supported. We know that a diversity of backgrounds, perspectives and experiences strengthens our teams and is vital to the work we do.

Please be aware that many roles at BAE Systems are subject to both security and export control restrictions. These restrictions mean that factors such as your nationality, any nationalities you may have previously held, and your place of birth can restrict the roles you are eligible to perform within the organisation. All applicants must as a minimum achieve Baseline Personnel Security Standard. Many roles also require higher levels of National Security Vetting where applicants must typically have 5 to 10 years of continuous residency in the UK depending on the vetting level required for the role, to allow for meaningful security vetting checks.

Closing Date: 14th April 2026

We reserve the right to close this vacancy early if we receive sufficient applications for the role. Therefore, if you are interested, please submit your application as early as possible.

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