IMPROVING AIRCRAFT ENERGY EFFICIENCY.

A NASA task force has reviewed possible advances in all areas of aeronautical technology, and defined a number of major programs that could conserve fuel use by air transports. These advances include the development of high-bypass engines in the 20,000-25,000-lb-thrust class ( ″ten-ton″ engines), the development of technology to improve existing engines, the development of a fuel-conservative engine involving the use of advanced turbofans and unconventional variants, and the development of a Mach 0. 8, 30,000-ft-cruise transport with a turboprop propulsion system. The task force also considered four potential improvements to the aerodynamic efficiency of aircraft, namely, the use of winglets mounted on the tip of the main wing, drag cleanup, improved aerodynamic design, and laminar flow control through pumping. A final area of consideration is the development of composite materials for primary aircraft structures.