NASA and Boeing have tested a new drone that can hit incredible speeds due to a material innovation that allows the wings to dynamically change shape and position based on flight needs.
The principle of reducing drag on a plane is not new, but the new design shows a significant improvement in overall performance for flights of this type. “From the time we started initial testing here at Boeing, up to the flight tests, the material behaved consistently stable, and showed a superior performance to previous materials,” says Jim Mabe, a researcher at Boeing.
The material is called shape memory alloy, and while the concept has been around for almost a century, these new capabilities are groundbreaking. Shape memory alloy can be deformed and reshaped while at room temperature, but when they are heated up they return to their original position. The metal changes "phase" at a very specific temperature, meaning the actuators don't need to heat or cool the object very much in order to get it to respond. Shape memory alloys are also extremely durable and can return to their original shape even after a significant stress has been placed on them. NASA's little drone was able to shift its wingtips from 0 degrees to 0 degrees in their successful flight tests.
The alloy was molded into an actuator, allowing the wings to change shape mid-flight to properly adjust for wind and speed conditions. The device used to change the temperature of the alloy is significantly lighter and more compact than motors and joints, allowing machinery to fit in a much smaller space.
The material is very interesting and has a number of unique properties that make it viable in other industries as well. Its coolest quality is its malleability, but without one other key feature, it would be useless in aircraft: its weight. Because the alloy is extremely light, it can be placed anywhere on the plane. Using it in actuators allows engineers to replace what would otherwise be bulky and heavy steel machinery, significantly reducing the overall weight of the craft. According to NASA, crafts with this material may weight up to 80% less than current crafts.
Weight has been a huge concern in aircraft design since the Wright Brothers. The two engineers that crafted the first human-piloted flying machine had to create their own engine because existing ones were made out of steel and were far too heavy. The development of super light materials makes way for impressive new designs. Not only does this allow for smaller crafts to reach supersonic speeds, but it might also innovate larger crafts too; lighter crafts are more fuel efficient, and more moving parts means they will be able to go more places and offer higher controllability in the air.