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Small, W. J.

Publications and source records attributed to Small, W. J..

15 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

Aerodynamic tests and analysis of a turbojet-boosted launch vehicle concept (spacejet) over a Mach number range of 1.50 to 2.86

Results from analytical and experimental studies of the aerodynamic characteristics of a turbojet-boosted launch vehicle concept through a Mach number range of 1.50 to 2.86 are presented. The vehicle consists of a winged orbiter utilizing an area-ruled axisymmetric body and two winged turbojet boosters mounted underneath the orbiter wing. Drag characteristics near zero lift were of prime interest. Force measurements and flow visualization techniques were employed. Estimates from wave drag theory, supersonic lifting surface theory, and impact theory are compared with data and indicate the ability of these theories to adequately predict the aerodynamic characteristics of the vehicle. Despite the existence of multiple wings and bodies in close proximity to each other, no large scale effects of boundary layer separation on drag or lift could be discerned. Total drag levels were, however, sensitive to booster locations.

Riebe, G. D.↗
NASA NTRS1981

Orbiter/launch system

The system includes reusable turbojet propelled booster vehicles releasably connected to a reusable rocket powered orbit vehicle. The coupled orbiter-booster combination takes off horizontally and ascends to staging altitude and speed under booster power with both orbiter and booster wings providing lift. After staging, the booster vehicles fly back to Earth for horizontal landing and the orbiter vehicle continues ascending to orbit.

Jackson, L. R.↗
NASA NTRS1980

Aerodynamics of a turbojet-boosted launch vehicle concept

Results from analytical and experimental studies of the aerodynamic characteristics of a turbojet-boosted launch vehicle are presented. The success of this launch vehicle concept depends upon several novel applications of aerodynamic technology, particularly in the area of takeoff lift and minimum transonic drag requirements. The take-off mode stresses leading edge vortex lift generated in parallel by a complex arrangement of low aspect ratio booster and orbiter wings. Wind-tunnel tests on a representative model showed that this low-speed lift is sensitive to geometric arrangements of the booster-orbiter combination and is not predictable by standard analytic techniques. Transonic drag was also experimentally observed to be very sensitive to booster location; however, these drag levels were accurately predicted by standard farfield wave drag theory.

Small, W. J.↗
NASA NTRS1979

Arbitrary aircraft-geometry generator

Computer program helps designers to generate detailed configuration geometry with much flexibility in choices of configurations and details of description. Input requirements, program turnaround time, and costs are kept low. It consists of routines that generate fuselage and planar-surface (winglike) geometries and routine that determines true intersection of all components with fuselage.

Edwards, C. L. W.↗
NASA NTRS1977

GEMPAK: An arbitrary aircraft geometry generator

A computer program, GEMPAK, has been developed to aid in the generation of detailed configuration geometry. The program was written to allow the user as much flexibility as possible in his choices of configurations and the detail of description desired and at the same time keep input requirements and program turnaround and cost to a minimum. The program consists of routines that generate fuselage and planar-surface (winglike) geometry and a routine that will determine the true intersection of all components with the fuselage. This paper describes the methods by which the various geometries are generated and provides input description with sample input and output. Also included are descriptions of the primary program variables and functions performed by the various routines. The FORTRAN program GEMPAK has been used extensively in conjunction with interfaces to several aerodynamic and plotting computer programs and has proven to be an effective aid in the preliminary design phase of aircraft configurations.

Stack, S. H.↗
NASA NTRS1977

A fully reusable, horizontal takeoff space transport concept with two small turbojet boosters

Results of a preliminary study of a space transport concept are presented. The concept consists of a winged orbiter containing ascent propellants and two small turbojet-powered winged boosters, used for acceleration to supersonic speeds. The concept offers full reuse and horizontal takeoff from numerous existing airports. With current structure and rocket technology, this transport concept has lower gross weight for a selected payload than single-stage-to-orbit concepts, which require structural advancements. Discussion includes alternatives to the baseline space transport concept which improve performance; such as advanced structures, dual-fuel rockets, and lightweight scramjets for the orbiter. A concept of using a stretched shuttle orbiter instead of an all-new configuration is discussed for two payload-class vehicles.

Jackson, L. R.↗
NASA NTRS1976

Scramjet nozzle design and analysis as applied to a highly integrated hypersonic research airplane

Engine-nozzle airframe integration at hypersonic speeds was conducted by using a high-speed research aircraft concept as a focus. Recently developed techniques for analysis of scramjet-nozzle exhaust flows provide a realistic analysis of complex forces resulting from the engine-nozzle airframe coupling. By properly integrating the engine-nozzle propulsive system with the airframe, efficient, controlled and stable flight results over a wide speed range.

Small, W. J.↗
NASA NTRS1976

Scramjet integration on hypersonic research airplane concepts

Several rocket-boosted research airplane concepts were evaluated with a research scramjet engine to determine their potential to provide research on critical aspects of airframe-integrated hypersonic systems. Extensive calculations to determine the force and moment contributions of the scramjet inlet, combustor, nozzle, and airframe were conducted to evaluate the overall performance of the combined engine/airframe system at hypersonic speeds. Results of both wind-tunnel tests and analysis indicate that it is possible to develop a research airplane configuration that will cruise at hypersonic speed on scramjet power alone, and will also have acceptable low-speed aerodynamic characteristics for landing.

Weidner, J. P.↗
NASA NTRS1975

Studies of scramjet/airframe integration techniques for hypersonic aircraft

New design and analysis techniques for engine-airframe integration were applied in a recent hypersonic vehicle design study. A new technique was developed to design the vehicle's forebody so that uniform precompressed flow was produced at the inlet entrance. Results are verified with three-dimensional characteristic calculations. Results from a new three-dimensional method for calculating nozzle flows show that the entire lower afterbody of the vehicle can be used as a scramjet exhaust nozzle to achieve efficient, controlled, and stable flight over a wide range of flight conditions.

Edwards, C. L. W.↗
NASA NTRS1974

Scramjet nozzle design and analysis as applied to a highly integrated hypersonic research airplane

The configuration and performance of the propulsion system for the hypersonic research vehicle are discussed. A study of the interactions between propulsion and aerodynamics of the highly integrated vehicle was conducted. The hypersonic research vehicle is configured to test the technology of structural and thermal protection systems concepts and the operation of the propulsion system under true flight conditions for most of the hypersonic flight regime. The subjects considered are: (1) research vehicle and scramjet engine configurations to determine fundamental engine sizing constraints, (2) analytical methods for computing airframe and propulsion system components, and (3) characteristics of a candidate nozzle to investigate vehicle stability and acceleration performance.

Small, W. J.↗
NASA NTRS1973

Potential of hydrogen fuel for future air transportation systems.

Recent studies have shown that hydrogen fuel can yield spectacular improvements in aircraft performance in addition to its more widely discussed environmental advantages. The characteristics of subsonic, supersonic, and hypersonic transport aircraft using hydrogen fuel are discussed, and their performance and environmental impact are compared to that of similar aircraft using conventional fuel. The possibilities of developing hydrogen-fueled supersonic and hypersonic vehicles with sonic boom levels acceptable for overland flight are also explored.

Small, W. J.↗