Futuristic aircraft wing with shape-shifting slat-cove filler reducing turbulence and noise.

Smart Wings: How Shape Memory Alloys are Revolutionizing Air Travel

Avery Sinclair in Tech & Innovation June 2025 • 5 min read.

"Explore the innovative use of shape memory alloys in slat-cove fillers to reduce airframe noise and improve aerodynamic performance, paving the way for quieter, more efficient flights."

For decades, air travel has been a marvel of engineering, connecting people and cultures across vast distances. However, the environmental impact of aviation, particularly noise pollution, has become a growing concern for communities near airports. Aircraft produce significant airframe noise during approach and landing due to geometric discontinuities. One major contributor to this noise is the leading-edge slat, a high-lift device deployed to improve aircraft performance at lower speeds.

The noise generated by these slats is the disruption of airflow, especially in the cove area just behind the slat. Shape Memory Alloys (SMAs) present a fascinating solution. SMAs are special materials that can remember a shape. Engineers are experimenting with something called a slat-cove filler (SCF) made from SMA. Imagine a material that can fill in that noisy gap when the slat is extended, making the airflow smoother and the flight quieter. In prior studies, it was shown to reduce the airframe noise by filling in the area aft of the slat and stopping air circulation.

Now, scientists are building on this idea. Using both computer models and real-world experiments, they're exploring how an SMA-based SCF can adapt to different flight conditions, all while reducing noise. This research is about finding ways to make air travel quieter, more efficient, and more environmentally friendly. As concerns grow about noise pollution near airports, it's more important than ever to minimize noise during landing. This is the future of flight.

The SMA Slat-Cove Filler: A Deep Dive

Futuristic aircraft wing with shape-shifting slat-cove filler reducing turbulence and noise.

The core of this revolution is the SMA slat-cove filler, a device designed to smooth airflow over the wing by filling the cove aft of the leading-edge slat. This eliminates the circulation region within the cove, which is a primary source of airframe noise. As the slat moves, the SCF will need to handle a great deal of air pressure and still be able to keep its shape. The design must reduce noise and keep airflow smooth for the wing to function properly. A team of researchers are pushing the boundaries of aviation technology. They aim to refine and improve existing designs, focusing on the adaptability and efficiency of a scaled high-lift wing incorporating a superelastic SMA SCF.

Computational fluid dynamics (CFD) analyses, using real-world turbulence measurements from the Texas A&M University wind tunnel, helps provide a more accurate representation of airflow. These CFD models are then coupled with structural finite element models, allowing for fluid-structure interaction (FSI) analysis of the SCF. This is crucial for understanding how the SCF will deform under aerodynamic loads. Both fully-deployed and retraction/deployment cases are being considered. Measurement of SCF displacement is conducted using laser displacement sensors and digital image correlation systems to capture the SCF’s behavior.

Noise Reduction: Fills slat cove to eliminate air circulation and reduce noise.
Aerodynamic Efficiency: Smoothes airflow for better wing performance.
Adaptive Design: SMA allows for shape change to adjust to flight conditions.
Real-World Testing: Validated with wind tunnel experiments.

To address the lack of structural stiffness in 3D-printed plastic slats during retraction and SCF stowage, a rigid steel slat is incorporated into the physical model. Researchers conduct preliminary wind tunnel tests at multiple angles of attack. This hybrid approach of computational modeling and experimental validation provides a robust framework for evaluating and optimizing the SMA SCF design. The overarching goal is to make air travel quieter and more environmentally friendly while maintaining or improving aircraft performance.

The Future of Quieter Skies

This research represents a significant step toward quieter and more sustainable air travel. By harnessing the unique properties of shape memory alloys, engineers are developing innovative solutions to reduce airframe noise and improve aerodynamic efficiency. As the aviation industry continues to evolve, advancements like the SMA slat-cove filler promise to play a crucial role in shaping the future of flight.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1115/smasis2018-8129, Alternate LINK

Title: Aerodynamic And Structural Evaluation Of An Sma Slat-Cove Filler Using Computational And Experimental Tools At Model Scale

Journal: Volume 1: Development and Characterization of Multifunctional Materials; Modeling, Simulation, and Control of Adaptive Systems; Integrated System Design and Implementation

Publisher: American Society of Mechanical Engineers

Authors: William Scholten, Ryan Patterson, Makiah Eustice, Sebastian Cook, Darren Hartl, Thomas Strganac, Travis Turner

Published: 2018-09-10

Everything You Need To Know

What are Shape Memory Alloys (SMAs), and how are they being utilized in aviation to reduce airframe noise?

Shape Memory Alloys (SMAs) are unique materials that can revert to a predetermined shape when subjected to a specific stimulus, like temperature change. In aviation, this property is used in the design of slat-cove fillers (SCFs). These fillers adapt to different flight conditions, which helps to reduce airframe noise by smoothing the airflow over the wing when the slat is extended. This capability addresses the issue of geometric discontinuities that cause air turbulence and noise.

How do SMA slat-cove fillers (SCFs) work to reduce noise, and what design considerations are important?

Slat-cove fillers (SCFs) made from Shape Memory Alloys (SMAs) are designed to fill the cove area behind the leading-edge slat on an aircraft wing. By filling this space, the SCF eliminates the circulation of air in the cove, which is a major source of airframe noise during landing and approach. The design of the SCF must balance the need for noise reduction with the need to maintain smooth airflow and proper wing function.

What role do computational fluid dynamics (CFD) analyses play in the development and testing of SMA slat-cove fillers (SCFs)?

Computational fluid dynamics (CFD) analyses are utilized in the design and testing of SMA slat-cove fillers (SCFs). CFD models simulate airflow around the wing and SCF, using real-world turbulence measurements to provide accurate representations. These models are coupled with structural finite element models for fluid-structure interaction (FSI) analysis. FSI analysis helps engineers understand how the SCF will deform under aerodynamic loads, ensuring that the design is both effective and durable. Laser displacement sensors and digital image correlation systems measure the SCF’s behavior.

How does the use of SMA slat-cove fillers (SCFs) affect air travel beyond noise reduction, and what are the broader implications?

The use of SMA slat-cove fillers (SCFs) directly addresses the issue of airframe noise, particularly during the approach and landing phases of flight. Airframe noise is caused by airflow disruption around parts of the aircraft, such as the leading-edge slats. By smoothing airflow, SCFs reduce noise pollution near airports. While the text focuses on noise reduction, this technology could also influence fuel efficiency and reduce the carbon footprint of air travel.

What are the current challenges in developing SMA slat-cove fillers (SCFs), and how are researchers addressing them?

One challenge in the development of SMA slat-cove fillers (SCFs) is ensuring the structural stiffness of the slat during retraction and stowage, especially when using 3D-printed plastic models. To address this, a rigid steel slat is incorporated into physical models for testing. Researchers conduct wind tunnel tests at various angles of attack to evaluate and optimize the SCF design. This iterative process, combining computational modeling and experimental validation, is crucial for creating effective and reliable SCFs.