Principal Stress Engineer

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, including antenna installations and fuselage changes
Perform and review classic stress analysis hand calculations and finite element analysis
Act as a technical representative during customer meetings such as ITCM, PDR, CDR, and FAI
Provide on‑site engineering support to customers during the aircraft embodiment phase when required
Promote a strong engineering and compliance culture across the organisation

Minimum Qualifications

Bachelor's degree in Aerospace, Aeronautical, or Mechanical Engineering

Skills & Experience

Current or recent experience within the aerospace industry, ideally in an EASA Part 21J Design Organisation (or equivalent)
Strong knowledge of aircraft interior and/or primary structure modification practices and interfaces
Proficiency in:
Classical stress analysis and hand calculations
Finite Element Analysis (FEA)
Technical report writing and compliance documentation
Working knowledge of EASA regulatory and airworthiness requirements, including CS‑25, (E)TSO, JAR‑25, and FAR 25 (structures/stress related)
Experience with aircraft interior reconfiguration and primary/secondary aircraft structures
High attention to detail and strong professional integrity
Ability to manage multiple programmes with varying priorities
Flexible, organised, and able to adapt to changing project demands

About You

A person of integrity who values trust, honesty, and respect
Comfortable working in a collaborative, global engineering environment
Willing to share knowledge and openly acknowledge limitations
Adaptable, resilient, and motivated by high standards and ambitious goals