Adaptive wing-tip design for pollution reduction

Most of the commercial long-range aircraft are equipped with winglet to decrease the induced drag thus saving more fuel; this feature can also be found on birds, but in conventional aircraft, the winglet device is fixed. Recent projects point toward advanced smart materials and telescopic wing-tip devices to obtain an adaptive morphing shape that gives, through performances improvement, a fuel consumption and so a pollutant reduction. In order to obtain pollution reductions via high aerodynamic efficiency, the design of a telescopic inflatable variable height wing-tip device has been addressed. The span variation is pursued toward a telescopic device that is linked to an inflatable system distributed in chord and along the base of tip, ready to be extruded according to flight conditions. The performance analysis has been conducted especially to evaluate range performance, which mainly provides the relation to fuel consumption. The hinged telescopic device gives the chance of obtaining variation in winglet span according to flight condition requirements in terms of stability and aerodynamic efficiency. The solution of the inflatable system would guarantee a more comfortable arrangement of deployment system and just minor surplus of weight compared to classical winglet solutions, with all the subsequent advantages.