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The design and recovery considerations are presented for a staged supersonic transport (SSST). It is shown that the SSST offers economic benefits over the conventional SST. The SSST benefits from the ability to “optimize” the design for minimum drag during supersonic cruise without the penalties of: landing gear, extensive flaps for landing, and the meeting of FAR 36 noise requirements. The recovery considerations are also presented to validate the SSST concept.

An economic analysis is presented of a composite (= staged) configuration option to a supersonic transport with transatlantic range. It is shown that the staged approach offers economic advantages over a conventional SST. A staged SST offers the possibility of ‘optimizing’ the configuration for the cruise flight condition, does not require flaps nor landing gear, does not carry any penalty for meeting FAR 36 takeoff and landing noise requirements and causes up to 30% less stratospheric pollution. Therefore, despite the potential for operational problems with launch and recovery, the staged SST option may have to be taken seriously.

A wind tunnel investigation was made of a new high-lift system consisting of a leading edge cusp flap combined with split upper and lower trailing edge flaps. The idea behind the system was to generate two strong spanwise vortices that would increase maximum lift and drag simultaneously. Test results were not encouraging. The spanwise vortices were observed, but were not sufficiently strong to generate the anticipated high lift. Several interesting flow phenomena were observed and are described. The purpose of this paper is to present a summary of results obtained from this wind tunnel test program.

This paper presents the results of an investigation into the design of advanced commuter configurations. The airplanes were required to carry 30 passengers over a 600 n.m. stage length at a cruise Mach number of 0.6 at an altitude of 28000 feet. The airplanes were required to have inherent static stability. Five unconventional twin turboprop configurations were investigated. These consisted of three canard and two 3-surface configurations. To provide separation of passengers and crew from the plane of the propellers and engine turbine and compressor discs, aft-mounted pusher-propeller configurations were adopted. This also resulted in a saving in the amount of sound proofing (weight). High wing loading was chosen to reduce wetted area and achieve good ride qualities. The combination of high wing loading and the required inherent static stability made it extremely difficult to realize canard configurations.

This paper describes work done under a NASA-Langley grant at the university of Kansas Flight Research Laboratory in the area of natural laminar flow and regional aircraft. The focus of this paper is on the application of natural laminar flow over various major wetted areas. In particular, efforts were concentrated on analyzing the potential benefits of achieving extensive laminar flow on the wing, empennage, and fuselage. The effect of the presence of large amounts of laminar flow is evaluated in terms of performance and efficiency improvement over an all-turbulent baseline aircraft. An introduction is given to the concept of regional aircraft, and the aerodynamic characteristics are compared to those of other airplane classes. Some recent aerodynamic developments are presented that justify, to a certain extent, the assumptions made concerning the amount of natural laminar flow that is possible for each surface.

This paper presents examples of how severe and/or novel design requirements can ‘drive’ an airplane designer to select a ‘unique’ configuration. Examples to illustrate this are given for the flying wing, for two- and for three-surface canards and for joined wing airplane configurations. Brief historical reviews are also provided.