German research company DLR completed wind tunnel tests early this month on a unique new concept in wing-leading-edge design. Rather than slats, the new-concept wing has a leading edge that changes shape internally, “drooping” to a higher-lift airfoil configuration without the drag and noise of leading edge slats.
The design uses a flexible glass-fiber reinforced material shaped by internal actuators and movable support structure.
“The leading edge can be lowered by up to 20 degrees with virtually no loss of lift,” said project leader Markus Kintscher of DLR’s Institute of Composite Structures and Adaptive Systems in Braunschweig, Germany.
The tests were conducted in one of Europe’s largest wind tunnels at the Russian Central Aerohydrodynamics Institute (TsAGI) at its Zhukovsky research facility near Moscow. With the newly conceived structure, a wing can also be reconfigured to maximize laminar flow at high speeds, enhancing efficiency and reducing drag by up to 12 percent, according to DLR.
Department head Hans-Peter Monner said, “On the one hand, the structure needs to be very elastic to enable it to morph to the required shapes, but on the other it has to be very rigid. The leading edge must bear around one third of the weight of the aircraft during landing.”
The next round of tests will involve adapting the new technology to accommodate requirements for lightning protection, anti-icing and protection from bird strikes.