Advanced design of a full-scale active morphing droop nose

Abstract

This paper describes the design of a morphing droop nose conceived to increase the performance in high-lift conditions of a twin-prop regional aircraft, while ensuring the natural flow laminarity of the wing. Starting from the results obtained in a previous phase, mainly concerned with the performance augmentation, a detailed structural design is conducted. The main aim is the achievement of a feasible solution based on the use of conventional materials, such as aluminium alloy for the internal structure and glass-fibre for the skin. A finite element model of the complete device is generated for the three-dimensional shape quality evaluation and for the skin structural verification. Stress analyses on high-fidelity models of the single adaptive ribs are also performed. At the same time, various design aspects are evaluated, such as installation and inspection issues, actuation power, and weight considerations. All these requirements contribute to the definition of an advanced and complete solution for the device, up to the realization of a detailed CAD model. Final verification on the virtual prototype assesses the functionality of the device when attached to the wing-box. Moreover, the bird impact safety of the leading edge is demonstrated according to the certification rules.