Aviation Partners, Inc. (API), long known for its fuel-saving winglets, announced at NBAA 2015 that it has launched a joint-venture with FlexSys to market a new proprietary wing-morphing technology known as FlexFoil, which offers the potential for even better fuel economy.
Since its formation in 2000, Ann Arbor, Mich.-based FlexSys has been working on variable-geometry control surface mechanisms, which have been validated in NASA tests on a Gulfstream III, in which the flaps were replaced with seamless continuous surface units that can morph from -9 degrees to 40 degrees. The lightweight technology leverages the inherent elasticity in materials by distributing the stresses encountered in shape changing over a wide area, allowing not only a change in camber but enabling it to twist spanwise at a very high rate, according to FlexSys founder and CEO Sridhar Kota. “At the same time it is not only flexible but it is very important to know it is very strong, strong enough to withstand air-loads and also strong enough to last a lifetime of cycles,” he told reporters in Las Vegas.
The resulting continuous surfaces could mean a revolution in the design of aircraft control design. “Replacing conventional multi-jointed flaps and other control surfaces with smooth seamless surfaces has been an elusive goal for the aerospace industry for decades, said Kota. “After 15 years of R&D, and successful flight testing, the FlexFoil variable-geometry control surface mechanism ushers in a new frontier in aircraft design.”
In addition to fuel savings from reduced drag, the new technology could also make aircraft quieter by closing the gaps in wing control surfaces. “According to NASA about 40 percent of the airframe noise comes from those sections,” said Kota. The surfaces could eventually be utilized for mission-adaptive profiling, where operators can adapt the control surfaces for optimal shape depending on the phase of flight.
In addition to control surfaces, API (Booth C8113), which currently has 6,300 shipsets of blended winglets in service on Boeing commercial airliners as well as business jets, sees potential in the development of active winglets, which could change their dynamic loading. “By morphing the winglet we can get the same effect as toeing it in or changing the camber,” said API chairman and CEO Joe Clark.
Another area of opportunity for Aviation Partners FlexSys could come from the replacement of some deicing systems currently in use, involving boots and/or bleed air. “Deicing is most readily accomplished by a gradual torqueing of the surface in order to shed the ice, and the FlexFoil technology is ideally suited for that,” noted API COO Hank Thompson, who added that despite the possible definition of the technology by regulators as “new and unusual,” he expects a product based on this technology to be certified and flying within the next 18 to 24 months.