IIT Madras develops morphing skin to boost aircraft safety

What if aircraft wings could behave more like birds, adapting in real time to prevent dangerous stalls while also improving fuel efficiency?

Researchers from the Indian Institute of Technology Madras (IIT Madras) have developed a novel “morphing skin” concept inspired by bird flight that could help aircraft prevent aerodynamic stalls, improve lift, reduce drag and enhance overall flight safety.

The research was led by Dr Rinku Mukherjee of IIT Madras, who worked on the numerical code with IIT Madras alumnus Antony Samuel B and on the wind tunnel experiments and implementation with fellow alumnus Dr Aritras Roy.

This novel adaptive “external skin” reshapes itself in real time to prevent airflow separation, increase lift, reduce drag, and improve aircraft safety and fuel efficiency.

Bird-inspired skin could prevent aircraft stalls

An aerodynamic stall occurs when airflow separates from a wing, resulting in a sudden loss of lift and an increase in drag. When the wing can no longer generate enough lift to support the aircraft’s weight, the aircraft begins to lose altitude.

The study demonstrates a simple yet effective solution: a flexible external wing assembly that dynamically reshapes itself as airflow begins to separate. Rather than allowing airflow to separate, causing a stall and sudden loss of lift, the adaptive external skin adjusts to the airflow, keeping it attached and improving aircraft stability even at higher tilt angles.

One immediate application could be in commercial aviation, where the technology may enable safer take-offs and landings, especially on busy or short runways, by allowing aircraft to perform efficiently across a wider range of flight conditions. Its ability to increase lift while reducing drag could also help lower fuel consumption and emissions, supporting the aviation industry's efforts toward greater sustainability.

The findings were published in European Journal of Mechanics - B/Fluids (https://doi.org/10.1016/j.euromechflu.2025.204348), a peer-reviewed Elsevier journal that publishes theoretical, computational and experimental research across all areas of fluid mechanics.

The paper was co-authored by Dr Aritras Roy and Dr Rinku Mukherjee. Elaborating on the research, Dr Mukherjee, Associate Professor in the Department of Applied Mechanics and Biomedical Engineering at IIT Madras, said, “Our research taps into a universal curiosity in that birds rarely "stall," yet aircraft, despite being inspired by them, still do.”

The team sought to bridge this gap by mimicking nature’s adaptability through engineering and smart materials. The system combines predictive computational models with real-world wind tunnel testing and integrates Macro Fibre Composite (MFC) strips that can sense and actuate shape changes in real time, Mukherjee added.

“When a flight takes off, it always tilts itself to generate additional force to lift the airplane from the ground into the air. Sometimes the tilt can also happen due to some adverse flying conditions. In such conditions, the external skin (wing assembly attachment) tilts itself to a safe degree which continues to generate additional lifting force that keeps the airplane in air and/or prevents accidents,” said Mukherjee.

Early results are promising. The morphing skin not only prevents airflow separation but also increases lift while reducing drag, potentially making flights safer and more fuel-efficient. Crucially, the device continues to work beyond conventional operating limits, potentially giving pilots greater control in challenging conditions such as turbulence, bird strikes, or mechanical disturbances.

Sharing an update on the current status of the research and the potential timeline for real-world applications, Rinku Mukherjee said, “This research is more than 20 years old where we have taken a concept to study separated flow and converted it into a physical device to actually control flight properties in real-time. We have experimentally validated the concept and also tested test cases and patented the same. Hence, we are ready to implement this in real aircrafts in real-time flight conditions as we speak.”

Technology could improve efficiency and flight control

Beyond improving stall resistance, the research points to several potential real-world applications across aviation and related sectors. The morphing skin concept, tested on a 3D wing featuring a standard NACA 4415 airfoil, can dynamically change airflow characteristics without relying on complex mechanical systems, making it promising for next-generation aircraft design.

The technology could also benefit unmanned aerial vehicles (UAVs) and drones, where adaptive wings could improve endurance, manoeuvrability, and payload efficiency.

Since the design avoids heavy actuators and relies on passive or semi-active deformation, it is particularly suitable for smaller aircraft platforms where weight and energy constraints are critical, the research team said.

In defence and high-performance aviation, the technology could improve aircraft control during extreme manoeuvres, turbulence and combat scenarios, where maintaining stable airflow over the wings is crucial. Its ability to adapt wing behaviour in real time could enhance both survivability and mission

The relatively simple add-on design of the external skin could also allow it to be retrofitted onto existing aircraft, potentially lowering the barrier to adoption, they added. Instead of redesigning entire wings, manufacturers could integrate morphing surfaces to improve aircraft performance, making the technology potentially scalable and suitable for future industry applications.