SBIR-STTR Award

This innovation applies multiple winglets to reduce induced drag without increasing the span of aircraft wings. The advantages of conventional single winglets have been demonstrated on transport aircraft and business jets, and new designs are now incorporating them. However, biologists have shown that the multiple, individually controlled winglets used by soaring birds show significant improvement over single winglets, not only by reducing the overall magnitude of the tip vortices, but also through the active control of the individual winglet angles of attack, dihedral, and sweep during flight. This program will develop and demonstrate smart-structure-controlled multiple winglets that show potential for a variety of applications in aircraft, propellers, watercraft, and helicopter rotors. The multiple winglets will show significant improvements over the performance of single winglets, and the active control will allow them to be optimized over a wide range of flight conditions. The total combination of multiple winglets, smart structures, and active control will produce maximum reduction in induced drag, leading to improved performance and reduced fuel costs.

This program will produce prototypes of aircraft wingtip treatments to reduce induced drag without increasing span of aircraft wings, and to reduce wind dynamic responses for improved ride. The advantages of conventional winglets have been demonstrated on transport aircraft and business jets. Phase I of this effort demonstrated that even greater results can be obtained by modified winglets of new design. Phase II will develop and demonstrate prototype models of these new winglets that can be used for a variety of applications in unmanned air vehicles, general aviation craft, and commercial airliners. The incorporation of all the innovations proposed here will produce maximum reduction in induced drag, leading to improved range and endurance, and reduction on wing dynamic response, leading to improved ride quality and fatigue life.

Benefits:
Our new design for winglets will have wide commercial and military potential, which will be demonstrated by this Phase II program. For the Air Force, they will enable shorter wingspans for cruise missiles and uninhabited air vehicles, allowing for tighter storage and more weapons to be carried in space-limited cargo and bomber aircraft holds. In general aviation aircraft, they can be retrofitted for improved fuel economy. For airliners, they can improve ride quality and increase wing fatigue life. For wind turbines, they will allow higher power output with shorter span and lower towers. For watercraft, they could allow improved propeller performance with less draft.