Actively Controlled Multi-Winglets

Period of Performance: 05/03/2000 - 03/03/2001


Phase 1 SBIR

Recipient Firm

Star Technology and Research, Inc.
3213 Carmel Bay DriveSuite 200
Mount Pleasant, SC 29466
Principal Investigator


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. Multiple winglets will have wide commercial potential beyond this Phase I application to subsonic aircraft wings. For the military, they may 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. For sailplanes, they can improve performance in wingspan-limited competition classes, beyond a single winglet's capabilities. For wind turbines, they have the potential for higher power output with shorter span and lower towers. For watercraft, they make possible improved propeller performance without increased draft.