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The variable-geometry features of the United States supersonic transport are described. Particular attention is given to the hardware development of those variable-geometry features unique to the supersonic transport. ...Particular attention is given to the hardware development of those variable-geometry features unique to the supersonic transport. The design, development, and current status of a direct lift control sys tern, the supersonic internal-external compression inlet, and the full-scale wing pivot are described. ...The design, development, and current status of a direct lift control sys tern, the supersonic internal-external compression inlet, and the full-scale wing pivot are described.

A model scaled test apparatus has been designed and assembled to simulate supersonic plume/aircraft structure Interaction for the cruise configuration. Preliminary results have been obtained to demonstrate the severity of the associated acoustic fatigue loads. ...Two rectangular supersonic nozzles with aspect ratios of 7 and 7.7 ware fabricated with internal convergent-divergent contours designed for Mach numbers of 1.35 and 2.00. ...Phase averaged schliern measurements revealed the presence of high intensity acoustic emission from the supersonic plume above the plate and directed upstream. This radiation can be associated with the shock noise generation mechanism.

Variable Cycle Engines being studied for advanced commercial supersonic transports show potential for significant environmental and economic improvements relative to 1st generation SST engines. ...Unique fuel control techniques are combined with cycle characteristics that provide low fuel consumption, similar to a turbojet engine, for supersonic operation. This is accomplished while retaining the good subsonic performance features of a turbofan engine. ...In total, these unique engine concepts have the potential for significant overall improvements to the environmental and economic characteristics of advanced supersonic transports.

SOME of the aerodynamic and mechanical problems of jet engines designed for supersonic flight speeds are discussed in this paper. The aerodynamic problems considered include the required range of operation of the compressor, the thermal efficiency of the cycle, the inlet-engine airflow match, and jet nozzle design.

With the imminent development of the United States Mach 3 Supersonic Transport (SST), aircraft hydraulic fluid state-of-the-art must take another step forward to meet system performance requirements combined with high temperature environments.

This paper describes the methods employed in stabilizing stagnation temperature, settling chamber pressure and transonic Mach number in the 5 ft × 5 ft High Speed Wind Tunnel of the National Aeronautical Establishment, Ottawa, Canada. Under the most demanding flow conditions a temperature drop of less than 10°F is achieved by 210 tons of thin walled tubing placed in the last 90 feet of the last of three storage vessels connected in series. Pressure in the settling chamber is maintained constant within ± 0.5% over the range 1.8 to 13.5 atmospheres by a specially designed 72" diameter sleeve valve and matching feedback control system. The valve also incorporates a unique safety feature - that of physically preventing the valve from over-opening and hence over-pressuring the tunnel circuit in the event of a control system malfunction.

A record of excellent compatibility with induction systems of all installations has been established by the J79 engine in six air weapons operating at Mach 2 and above. The paper discusses the aspects of steady state matching, dynamic matching, inflow distortion, and compressor design. Studies show that the engine must be evaluated as a component of the propulsion system, and that dynamic matching is at least as important as steady state matching for air breathing engines at Mach 3 and above.

During the past several years, the world's major airlines have been planning for the introduction of inertial navigation into scheduled airline operation. This effort has resulted in the generation of ARINC Characteristic 561. Systems which have been designed to this characteristic are expected to enter airline service in 1968. A description of the configuration of the “561” system is presented which includes the various aircraft interfaces, system modes of operation, and the performance which can be realized from such a system. In order to extend the capabilities of the basic 561 system, the airlines are about to begin generating Characteristic 562 which will describe a digital computer whose function it is to perform additional computations incidental to the navigation problem and to extend the 561 interface. Such extension will be desirable, for instance, in navigating the SST. A discussion of some of the candidate 562 functions is presented.

The nozzle with design Mach number of 2.94 placed in a Mach 1.8 flow reveals that the nozzle can choke and deliver supersonic flow at its exit. In this paper the wall static pressure distribution along the length of the straight and slanted entry nozzle and its comparison with isentropic flow is discussed. ...The variation of inlet and exit Mach numbers for both straight and slanted entry nozzles run by a supersonic stream is also discussed. The separation location obtained by present experiment and from other empirical relations is compared.

This paper presents an approach to the design optimization of a conventional landing gear system for a supersonic transport, from a structural loads standpoint. Frequency analysis considerations are related to the computer simulated response of the nonlinear gear-airframe interacting system.

Our previous experimental results show that supersonic jets could extend the lean flammability limit of fuel/air mixtures in the main chamber in comparison to subsonic jets. ...The present paper investigated the characteristics of supersonic hot jets generated by combustion of stoichiometric H2/air in a pre-chamber to understand the ignition mechanism of ultra-lean mixtures by supersonic hot jets. ...The present paper investigated the characteristics of supersonic hot jets generated by combustion of stoichiometric H2/air in a pre-chamber to understand the ignition mechanism of ultra-lean mixtures by supersonic hot jets. Numerical simulations were carried out to examine the transient hot jets issued from six different nozzles (two straight nozzles, one converging nozzle, and three converging-diverging (C-D) nozzles) using a detailed H2/air chemistry.

An experiment has been developed to investigate the ignition characteristics of ultra-lean premixed H2/air mixtures by a supersonic hot jet. The hot jet is generated by combustion of a stoichiometric mixture in a small prechamber. ...The results show that a supersonic jet by using a converging-diverging nozzle can ignite leaner mixtures than the jet produced by a straight nozzle of the same throat area (e.g., the ignition limit is reduced to ϕ = 0.22, from 0.35). ...Additionally, infrared imaging and OH* Chemiluminescence indicated diamond shock structures in the supersonic jets and a high-temperature zone downstream the shocks. This high-temperature zone is likely the reason why the main-chamber flammability limit can be further reduced.

With respect to engine cycles, it is shown that a new round of subsonic engines can be expected; for supersonic transports the cycle is needed which better matches both supersonic and subsonic flight requirements. ...Propulsion system requirements for subsonic and supersonic transports in the 1975 to 1985 period are presented from an airframe manufacturer’s point of view. ...The number one problem will be noise, with different detail problems to be solved for subsonic and supersonic transports. With respect to engine cycles, it is shown that a new round of subsonic engines can be expected; for supersonic transports the cycle is needed which better matches both supersonic and subsonic flight requirements.

Functional requirements and limitations of the Boeing supersonic inlet system are presented and several of the design considerations are discussed. Some trade studies are defined and examples of current hardware concepts are presented.

To develop a STOVL fighter design with supersonic capability requires the integration of an advanced propulsion system into the airframe design. ...A promising propulsion system for supersonic STOVL application is the relatively new Hybrid Fan Vectored Thrust (HFVT) concept. This advanced Tandem Fan concept incorporates a dual-cycle engine with front and rear fully vectorabie nozzles of the three-poster type, to provide the required performance.

This paper assesses the state of the art in acoustic fatigue technologies as applied to an advanced supersonic short takeoff and vertical landing (STOVL) aircraft. The topics covered include advanced materials, fatigue, acoustic loads prediction, and stress response prediction. ...Subsonic and supersonic jet noise generation mechanisms, axisymmetric and two-dimensional nozzles, and noise suppression methods are covered.

A study of the costs/benefits trade-off was conducted for an Advanced Supersonic Short Takeoff and Vertical Landing (ASTOVL) aircraft incorporating a jet flap. The data used were the theory of jet flaps and high-aspect-ratio nozzles, experience with the McDonnell V/STOL aircraft study performed for NASA Ames Research Center in February 1982, and a high-performance aircraft-synthesis program (ACSYNT). ...The methodology was to accurately model the McDonnell supersonic Harrier V/STOL aircraft design on ACSYNT, and then modify the design by both adding high aspect-ratio (AR) nozzles in place of the rear (core-flow) nozzles on the Pegasus-type turbofan engine, and integrating these nozzles on each wing's trailing edge, thus creating a jet flap.

THIS paper deals with the general performance of turbojet engines in both subsonic and supersonic flight in relation to aircraft requirements. The advantages and disadvantages of the bypass engine and small turbojet in relation to the large straight jet engine of 18,000-lb thrust are examined.

Air Force XB-70 and B-1 bombers and a number of European aircraft including the tornado multirole combat aircraft and the Concorde supersonic transport. The V-22 Osprey incorporates a 5000 psi hydraulic system. The power levels of military aircraft hydraulic systems have continued to rise.