Job Title: Principal Systems Engineer Duration: 12-Month Rolling Contract Location: On-site – South West England (Hybrid with on-site presence required) Hourly Rate: £70.00 – £80.00 (Inside IR35) Clearance: Current SC Clearance (or eligibility) required Principal / Senior Systems Engineer We are seeking an experienced Principal / Senior Systems Engineer to support a long-term, high-security engineering programme focused on delivering advanced systems solutions across aerospace, defence, and marine domains. This role involves full lifecycle systems engineering, from requirements management through to integration, verification & validation, and delivery of complex platform-based systems. Requirements: * Proven experience as a Senior or Principal Systems Engineer within defence, aerospace, or maritime sectors * Strong understanding of systems engineering lifecycle, including requirements capture, architecture design, integration, and V&V * Hands-on experience with integration and qualification activities * Ability to contribute to bids, technical estimates, and work package planning * Current SC Clearance (or ability to obtain) * UK work authorisation required Desirable: * Familiarity with system modelling and analysis (e.g., SysML, MBSE) * Experience with trade studies, concept assessments, and performance analysis * Strong documentation skills for design reports, test plans, and compliance ev...