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Subsonic and supersonic aerodynamic characteristics of aircraft configuration using double pivot variable sweep wings
Rolling stability derivatives of variable sweep tactical fighter aircraft model at subsonic and transonic speeds
A Mach-3.0, 250-passenger, 6500-n. mi. range SST configuration's alternative use of fixed-planform or variable-sweep wings is presently evaluated, with a view to effects on aerodynamics, mission performance, and sizing. After preliminary design, the fixed and variable-wing configurations were resized to perform missions incorporating subsonic cruise segments of as much as 4000 n. mi.; the effect of subsonic segment length on design gross weight and block time was then ascertained. Due to the reduced supersonic efficiency of the variable-sweep aircraft, over one-half of the 6500-n. mi. mission would have to be flown subsonically for its sizing to reach a lower ramp weight than that of its fixed-geometry counterpart.
Transonic aerodynamic stability and damping in yaw and pitch for variable sweep supersonic transport model
Wing pivot location effect on longitudinal aerodynamic characteristics of variable sweep wing having M planform
Transonic aerodynamic characteristics of two variable sweep aircraft configurations capable of low level supersonic attack
Longitudinal aerodynamic characteristics at transonic speeds of two V/STOL aircraft configurations with skewed and variable sweep wings
Static longitudinal and lateral aerodynamic characteristics of V/STOL aircraft with variable sweep wing
Large scale wind tunnel investigation of low speed aerodynamic characteristics of supersonic transport model having variable sweep wings
The impact of variable sweep wing technology with relaxed static stability requirements on a supersonic-cruise executive jet with transatlantic range was assessed. The baseline vehicle utilized modified, current-technology engines and titanium structures produced with superplastic forming and diffusion bonding; this vehicle meets study requirements for both supersonic-cruise and low-speed characteristics. The baseline concept has a ramp weight of 64,500 pounds with a crew of two and eight passengers. Its Mach 2.0 cruise range is nearly 3,500 nautical miles; its Mach 0.9 cruise range is over 5,000 nautical miles. Takeoff, landing, and balanced field length requirements were calculated for a composite variant and are all less than 5,000 feet.
Longitudinal aerodynamic characteristics at transonic speeds of V/STOL aircraft configuration with fixed delta wing having auxiliary variable sweep outboard panels
Wind tunnel flutter analysis of simplified component models of variable-sweep-wing airplane at Mach numbers up to 3
High lift characteristics of variable-sweep transport model with blended engine-fuselage and engine-mounted horizontal tails
Low speed wind tunnel testing of high aspect ratio variable sweep wing supersonic transport model for determining methods of reducing pitch-up tendency
Leading edge and trailing edge flap deflection effect on high left and lateral control characteristics of semispan variable sweep wing and tail surfaces
Transonic and supersonic dynamic stability characteristics of variable sweep wing tactical fighter aircraft
An investigation of air flow over the aft portions of a variable sweep fighter aircraft configuration was made. Tests conducted in the unitary plan wind tunnel at Mach number 2.16 included measurements of forces, moments, and local static pressures as well as visual recordings of the air flow. An aerodynamic analytical prediction method was evaluated when used in data comparison at angles of attack of 0, 5, and 15 degrees. The results indicate that in supersonic flow the typical outboard located twin vertical tail arrangement tends to provide a more positive increment in normal-force on the afterbody fuselage and the horizontal tail than a single center-mounted vertical tail of similar planform shape. In addition, the results indicate that a method for aerodynamic analysis of wing-body-tail configurations currently available can provide reasonable estimates of pressure coefficient distributions on configurations in regions of complex supersonic flow. At this time, however, the available analytical method cannot adequately replace experimental wind tunnel tests for determining the supersonic flow environment of a given configuration.
NASA Langley and NASA Ames-Dryden have defined a variable-sweep transition-flight experiment utilizing the F-14 aircraft to enhance understanding of the interaction of crossflow and Tollmien-Schlichting instabilities on a laminar-boundary-layer transition. The F-14 wing outer panel will be modified to generate favorable pressure gradients on the upper wing surface over a wide range of flight conditions. Extensive computations have been performed using two-dimensional and three-dimensional transonic analysis codes. Flight-test and computational data are compared and shown to validate the applicability of the three-dimensional codes (WBPPW and TAWFIVE). In addition, results from two preliminary glove designs derived from two different approaches to the design problem are presented. Advantages and disadvantages of each approach are identified, and it is concluded that coupling an analysis code with an automated design procedure yields a powerful code with distinct advantages over a 'cut-and-dry' approach.