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This paper describes a numerical method for solving three-dimensional incompressible flow problems and its use in predicting the aerodynamic characteristics of V/STOL aircraft. Arbitrary configuration and inlet geometry, fan inflow distributions, thrust vectoring, jet entrainment, angles of yaw, and flight speeds from hover through transition can be treated. Potential-flow solutions are obtained with the method of influence coefficients, using source and doublet panels distributed on the boundary surfaces. The results include pressure distributions, lift, induced drag and side force, and moments. Theoretical solutions are presented for clean lifting wings and for a NASA fan-in-wing model. Comparisons with the experimental NASA data demonstrate the validity of the approach and uncover the importance of viscous effects, fan inflow distribution, and jet entrainment.

The concept of powered wheels as applied here is the propelling of an airplane on the ground by direct traction of landing gear wheels using onboard power and under direct control of the pilot. This concept suggests an improvement in economic and ecologic factors associated with ground operation of commercial transport airplanes. For the concept to be economically feasible, penalities for addition of airborne equipment must be overbalanced by savings in fuel, engine operating time, ground equipment, ground personnel, and terminal space, and by increased airplane productivity. The use of direct wheel traction can improve the airport and terminal environment by reducing air pollution, jet blast, and noise from main propulsion engines during taxi and parking. This paper is a preliminary look at requirements, configurations, and trades that require further investigation to establish the role of powered wheels in future air transportation.

Significant advances in transonic airfoil technology have occurred during the last decade in Europe and in the United States. Some of this new technology, available in the open literature, could be applied to business aircraft. The phenomenological differences between the flow characteristics of the newer transonic airfoils and the conventional NASA-type airfoils are described. In particular, supercritical flow generation and recompression without shock-wave, boundary-layer interaction sufficiently strong to destroy the airfoil aerodynamic efficiency are emphasized. One deterrent to the use of improved transonic airfoils is the sophisticated design methodology required to transform an airfoil into a successful three-dimensional wing. Some techniques for designing compatible wings and fuselages, where a large percentage of their surfaces is covered with supercritical flow, are described.

The basic electromagnetic shielding of conventional riveted aluminum aircraft construction provides inherent protection to the aircraft systems and occupants against the hazards of lightning discharges. The increased use of adhesively bonded construction techniques on structures of future aircraft indicates a potential reduction in the basic electrical continuity of the airframe. The significance of the conductivity reduction on aircraft lightning protection will be evaluated for various proposed construction techniques, including: bonded honeycomb skin panels, bonded skin joints, bonded basic structure, and different types of monocoque construction. The discussion examines related problems that have been encountered in designing protection for aluminum aircraft.