Variable, multi-element winglets for aircraft control and stability
Group Members
Tom Brunt, Adam Challacombe, Prathiv Rao, Wan Iqra, Conor Walsh, Michael Clements
Professor Neil Bressloff
Sustainability is an increasingly key parameter in aircraft design, with targets to increase aerodynamic and fuel efficiency while reducing noise and pollution. In 2019 Airbus launched the Bird of Prey project, a conceptual airliner with the goal of inspiring the next generation of engineers. The Bird of Prey aircraft possesses features of biomimicry design, the purpose of which are to increase sustainability. The Unmanned Aerial Vehicle (UAV) designed in this project incorporated multi-element winglets directly inspired by those on the bird of prey airliner. The aircraft employed these winglets such that they can be used for roll control, using one element per wing as a tiperon. The aircraft had the ability to furl the remaining winglet elements to offer variable in-flight stability. To evaluate their effect, the aircraft was designed as a modular platform which allowed 3 possible modules for comparison. This included a clean wing section as well as fixed and furling winglets. The aircraft was designed from a blank canvas, predominantly using the computational methods finite element analysis (FEA) and computational fluid dynamics CFD. A full-scale prototype was manufactured for testing which was then improved into the final design. Extensive prototyping was undertaken on the mechanical systems designed to operate the furling wingtips. The multi-element winglets showed comparable performance to a square-tip wing during wind tunnel tests. According to CFD, subsequent changes to the winglet design displayed significant improvements in aerodynamic efficiency while maintaining similar roll authority. Unfortunately, due to Covid-19 further wind tunnel tests and flight tests could not be performed to evaluate the aerodynamic performance or the effect of the furling winglets on maneuverability.
Front view of aircraft assembly



Exploded view of aircraft
1. Multi-Element Winglets
2. Modular Winglet Housing
3. V-Tail Assembly
4. Carbon Fibre Fuselage Panels
5. Aluminium Fuselage Ribs
6. Electronics Assembly
7. Electric Ducted Fan


Furling winglet and tiperon assembly


Mark 1 winglet configuration mounted in the wind tunnel


Mark 1 clean wing smoke visualisation in the wind tunnel


Mark 1 winglet configuration mounted in the wind tunnel


Assembling the mark 1 for wind-tunnel testing


Assembling the mark 1 for wind-tunnel testing
Mark 1 clean wing configuration in the wind tunnel