Aircraft Modifications & Certification An established aerospace engineering organisation is seeking a Principal Stress Engineer to join its engineering team, supporting the certification of large aircraft modifications. The role focuses on demonstrating compliance with applicable regulatory and customer requirements in line with a Design Organisation Handbook (DOH). Locations: Frimley The Role Reporting to the Structures Engineering Manager, you will work closely with a global engineering team across multiple time zones. You will support active and upcoming aircraft modification programmes by identifying technical requirements, developing compliant solutions, and leading certification activities. You will act as a technical focal point for structures, stress, and certification, contributing to high‑profile large aircraft modification projects from concept through embodiment. Key Responsibilities Lead certification activities to ensure compliance with applicable design, regulatory, and customer requirements Identify technical requirements and develop compliant engineering solutions for active and future projects Compile, review, and approve structural substantiation documentation for: New seating installations Cabin monuments and furniture (galleys, lavatories, class dividers, first‑class suites, VVIP furnishings) Cabin interior changes (LOPAs, PSU layouts, LRU installations) Primary structure modifications, ...