Can feather-like flaps improve flight performance and reduce drag?

Bird-inspired wing flaps could be the future of aviation, as they can boost flight performance by improving lift and reducing drag. In a recent study, engineers explored how “hidden feathers” – the layered, overlapping feathers on bird wings – could be simulated on aircraft wings to improve maneuverability and stability. According to a study, installing lightweight, passive flaps over an aircraft’s wing surfaces could provide significant aerodynamic benefits, allowing aircraft to achieve greater lift and less drag.

A new approach to aircraft flap design

According to research published on October 28 in Proceedings of the National Academy of Sciences Traditional aircraft wings typically use flaps and spoilers controlled by mechanical systems to manage airflow during flight. However, this bio-inspired approach aims to replace complex controls with a passive design activated solely by air pressure changes at high angles of attack – the position where wings meet the incoming airflow head-on. Engineer Aimy Wissa, from Princeton University, explained that unlike conventional components, these flaps “are not controlled by motors or actuators,” but respond naturally to airflow, providing simplicity and coverage over the entire wing surface .

Wind tunnel tests reveal improved stability and lift

In wind tunnel tests, researchers examined the impact of these spring-like flaps on wing models. Flaps at the leading edge of the wing guided airflow more effectively, improving lift and reducing drag. Additional rows of flaps enhanced this effect, while swept-back flaps stabilized air pressure by preventing it from flowing forward, a crucial aspect of maintaining lift. The study found that a five-row flap design increased lift by 45% and reduced drag by 31%, highlighting the potential of these flaps to optimize aerodynamics without complex machinery.

Potential benefits for modern aviation

When tested on remote-controlled aircraft, the spring-like flaps also helped increase the range of safe flight angles by nine percent, reducing the chance of stall – a sudden loss of lift that often occurs during steep climbs or tight turns. This increased attack range could make flights safer, especially in turbulent conditions or during short runway landings. As Wissa noted, the passive flaps could support a wider range of maneuvers, offering benefits for various aviation applications, from commercial aircraft to drones.