A Novel Surrogate-Assisted Structural Optimization Framework for Full-Aircraft Configurations

Aircraft configurations; Aircraft structure; Conventional approach; Finite element modelling (FEM); High-fidelity; Kriging; Optimization framework; Parametric finite elements; Structural optimisations; Surrogate-based optimization; Aerospace Engineering

Abstract :

[en] Designing lighter, stronger, and more efficient aircraft structures is a constant challenge in aerospace engineering. To this end, the present study introduces a novel surrogate-assisted structural optimization framework for full-aircraft configurations, integrating a parametric Finite Element Model (FEM) of the uCRM-13.5 geometry with Kriging-based Surrogate-Based Optimization (SBO). Unlike conventional approaches, that either optimize isolated aircraft components or rely on low-fidelity models, the proposed framework simultaneously sizes the wing, fuselage, and tail, capturing realistic load paths and global interactions under three load cases (cruise, +2.5g, −1g), global buckling, and flutter constraints. Aerodynamic and aeroelastic loads are obtained using the subsonic Source and Doublet Panel Method (SDPM), while flutter stability is enforced through a Kreisselmeier–Steinhauser aggregation of modal damping ratios. The surrogate models achieve high accuracy, with root-mean-square errors of the order of 1% and g2 ≈ 0.997 relative to the high-fidelity FEM responses. Three independent SBO runs with different Latin Hypercube samples converge robustly to fully feasible optima with final structural masses of approximately (2.13 ± 0.02) × 105 kg, corresponding to less than 1.6% variation between runs. The +2.5g maneuver is identified as the governing sizing case, with beam and shell stress constraints in this condition being consistently active, while cruise, −1g, and flutter constraints remain comfortably satisfied. A direct comparison with the MIDACO global optimizer shows that, for a similar budget of a high-fidelity evaluation, the proposed SBO framework attains a feasible design that is around 5–7% lighter than the best-feasible MIDACO solution, while MIDACO exhibits highly oscillatory convergence. The results demonstrate that the developed framework enables efficient and robust high-fidelity, full-aircraft structural optimization, providing a practical bridge between detailed FEM analysis and efficient preliminary design.

Disciplines :

Aerospace & aeronautics engineering

Author, co-author :

Kilimtzidis, Spyridon; University of Patras, Rion, Greece

Kostopoulos, Vassilis; University of Patras, Rion, Greece

Dimitriadis, Grigorios ; Université de Liège - ULiège > Département d'aérospatiale et mécanique > Interactions Fluide-Structure - Aérodynamique expérimentale

Language :

English

Title :

A Novel Surrogate-Assisted Structural Optimization Framework for Full-Aircraft Configurations

Publication date :

12 January 2026

Event name :

AIAA SCITECH 2026 Forum

Event place :

Orlando, Usa

Event date :

12-01-2026 => 16-01-2026

Audience :

International

Main work title :

AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2026

Publisher :

American Institute of Aeronautics and Astronautics Inc, AIAA

ISBN/EAN :

978-1-62410-765-8

Peer review/Selection committee :

Editorial reviewed

Additional URL :

https://arc.aiaa.org/doi/pdf/10.2514/6.2026-0581

Available on ORBi :

since 05 June 2026

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