A winglet, like everything else on an airplane, represents a compromise between many factors, including cost, structure and performance. A winglet is a wing tip extension whose purpose is to improve aerodynamic efficiency. “Airflow around winglets is complicated, and winglets must be carefully designed and tested for each aircraft.” (How things work: Winglets). The invention of the winglet helps reduce the drag acting on the aircraft by converting the airflow at the wingtip into a forward force, rather than an upward force. The size, shape and angle at which an aileron is mounted on the wing depends on the type and size of the aircraft. A winglet improves the overall performance of the aircraft and is beneficial to the aviation industry as the aircraft will have improved fuel economy, reduced need for engine maintenance checks, ability to carry a greater load useful and will be better for the environment. The idea of ​​winglets was developed by FW Lancaster, a British aerodynamicist in the late 1800s. However, it was not until 1976, during an energy crisis, that caused the price of fuel to skyrocket , that Richard Whitcomb, a NASA aerodynamicist, took the Lancaster concept to the next stage. Whitcomb soon published a comparison between a wing with a winglet and the same wing with a simple wing extension to increase its wingspan. This article showed a significant improvement from just extending the wing to winging with the aileron. The winglet caused a reduction in drag and an improvement in the lift-to-drag ratio. Whitcomb proved that in theory the winglet would work, but it was Burt Rutan, an American aerospace engineer who designed his "Vari-Eze" to incorporate the "Whitcomb wings". "Rutan takes the winglets from the drawing...... middle of paper ...... advantage of drag reduction by reducing speed and saving fuel. Payload: Due to fuel saving Improved, winglets allow an aircraft to carry less fuel and more payload Allowing the company to save money on fuel and get more mileage out of payload. reduced means reduced emissions The fins would have reduced CO2 emissions by up to 6% and NOX by 8%. manual, p. 25) By reducing spanwise flow at the wingtip, winglets are therefore able to weaken vortices and significantly reduce drag. In cruise, minimal drag means performance. Winglets are now quite common in the aviation industry, making them "...one of the most successful examples of NASA aeronautical innovation used worldwide on all types of aircraft." (nasa.gov).