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Improvement in airframe structural efficiency through the utilization of unique and minimum weight concepts is a primary applied engineering objective for the hypersonic environment. The essential elements for hypersonic structures criteria are temperature environment, low load intensities, room temperature load conditions, structural stability, minimum gage material requirements, material producibility, reusability, nonoptimum factors, and vehicle configuration compatibility. ...A comparison of thermal structural concepts indicates that the hot load-carrying structure is the leading candidate for a typical M8 hypersonic cruise vehicle wing and fuselage application.

Hypersonic aeronautics research using the Pegasus® air-launched space booster is described. Two areas are discussed in the paper; previously obtained results from Pegasus flights 1 and 2, and plans for future programs. ...Proposed future research includes boundary-layer transition studies on the airplane-like first stage and also use of the complete Pegasus launch system to boost a research vehicle to hypersonic speeds. Pegasus flight 1 and 2 measurements were used to evaluate the results of several analytical aerodynamic design tools applied during the development of the vehicle as well as to develop hypersonic flight-test techniques. ...Pegasus flight 1 and 2 measurements were used to evaluate the results of several analytical aerodynamic design tools applied during the development of the vehicle as well as to develop hypersonic flight-test techniques. These data indicated that the aerodynamic design approach for Pegasus was adequate and showed that acceptable margins were available.

The status of the hypersonic research program at Stanford University is discussed and recent results are highlighted. ...The main areas of interest in the program are the numerical simulation of radiating, reacting and thermally excited flows, the investigation and numerical solution of hypersonic shock wave physics, the extension of the continuum fluid dynamic equations to the transition regime between continuum and free-molecule flow, and the development of novel numerical algorithms for efficient particulate simulations of flowfields.

The realization of unrefuled, hypersonic global range flight could have a significant impact on both commercial and military aircraft in the 21st century. ...This paper presents the results of a study done for the Air Force on the technical feasibility of an un-refueled, global range hypersonic aircraft. The results of the study indicate that it does not appear feasible in the foreseeable future to achieve an un-refueled hypersonic global range capability without a major technological break-through. ...The results of the study indicate that it does not appear feasible in the foreseeable future to achieve an un-refueled hypersonic global range capability without a major technological break-through. An un-refueled range capability in excess of 12,000 n. mi. may be possible to achieve sometime during the first decade of the 21st century.

The requirements for hypersonic air data measurement are reviewed, and techniques for the measurement of air data parameters for hypersonic vehicles are presented and assessed. Today's hypersonic vehicles, primarily the space shuttle, have had restricted flight envelopes and required minimal air data measurement performance. ...Advanced hypersonic vehicles are now being designed that will greatly expand the envelope of hypersonic travel. ...Accurate measurement or derivation of vehicle altitude, rates, Mach number, angle of attack, and sideslip are required to ensure that operation of a hypersonic vehicle over a broader envelope is possible. The hypersonic vehicle must operate in an environment characterized by low atmospheric and high dynamic pressures combined with high external-surface temperatures that reach extremes higher than 2000°C with flow velocities approaching Mach 25.

This report is a brief summary on the status of activities in hypersonic aerodynamics at The Ohio State University after the first year of support by a Hypersonic Training and Research Grant funded by the NASA, the Air Force OSR and the Navy ONR. ...The program now supports seven graduate students who are pursuing their degrees under a restructured curicullum which emphasizes the modern state of hypersonic aerodynamics. They participate in a research program which includes a variety of experimental activities.

The dominance of body-like shapes for hypersonic vehicles places emphasis on better understanding of pertinent body flow physics. Computational methods are implemented to enhance the knowledge of drag components generated by the production of lift forces at hypersonic speeds. ...Computational methods are implemented to enhance the knowledge of drag components generated by the production of lift forces at hypersonic speeds. Three forebody shapes are examined to identify the effects related to body shape parameters. ...In particular, it is noted that hypersonic body polar shapes are somewhat irregular; the result of incidence-induced form drag.

Numerical simulations of hypersonic flow around a 2-D cylinder and a 3-D complete reentry vehicle have been carried out by solving Euler/Navier-Stokes equations which incorporate the equation of state for an equilibrium gas. ...The results of hypersonic flow analysis using this code suggest us that the real gas effects, such as chemical reaction, are not negligible to predict the hypersonic flow characterisics acculately. ...The results of hypersonic flow analysis using this code suggest us that the real gas effects, such as chemical reaction, are not negligible to predict the hypersonic flow characterisics acculately.

Hypersonic Aerodynamics has attracted outstanding graduate students and faculty at NCSU. It has grown to 6 faculty and 32 graduate students for fall, 1988. ...The combined program produces graduates with the background needed to perform aerodynamics investigations of hypersonic aircraft and spacecraft. The research performed helps advance the state of the art as well as assist government laboratories in meeting their goals.

A transversely injected jet into a hypersonic flow is simulated numerically in order to study the flow field of the injection jet in the hypersonic atmosphere, its heat flux on the body surface and the moments working on the body. ...A transversely injected jet into a hypersonic flow is simulated numerically in order to study the flow field of the injection jet in the hypersonic atmosphere, its heat flux on the body surface and the moments working on the body. The flowfields is governed by the two-dimentional Reynolds averaged full Navier-Stokes equations with an algebraic eddy viscosity model developed by Baldwin-Lomax.

This paper describes a hypersonic cruiser concept for the 21st century. It is based on studies conducted by The Boeing Company and the National Aeronautics and Space Administration (NASA - Langley) to assess the capability of a hypersonic vehicle concept to conduct cruise and/or space launch missions. ...It is based on studies conducted by The Boeing Company and the National Aeronautics and Space Administration (NASA - Langley) to assess the capability of a hypersonic vehicle concept to conduct cruise and/or space launch missions. It details a Mach 10 cruise vehicle from NASA's Dual-Fuel Airbreathing Hypersonic Vehicle Design study (1995/96), and a Mach 10 cruise/space access vehicle, which resulted from follow-on work. ...It details a Mach 10 cruise vehicle from NASA's Dual-Fuel Airbreathing Hypersonic Vehicle Design study (1995/96), and a Mach 10 cruise/space access vehicle, which resulted from follow-on work.

Abstract To assist in initializing the conceptual design of hypersonic aircraft, we outline a new, systematic framework based on historical aircraft data and primarily composed of design data and regression models. ...An example is provided to demonstrate the application of the framework to launch the conceptual design of a new hypersonic aircraft with a given set of mission requirements.

Thermal protection systems (TPS) for hypersonic transport vehicles are described and evaluated. During the flight through the atmosphere moderate to high aerodynamic heating rates with corresponding high surface temperatures are generated. ...It is demonstrated that microporous and multiwall insulations are efficient, light weight and reliable TPSs for future hypersonic transportation systems.

A brief review of investigations in the field of advanced structural concepts and structure member with the aim of making a forecast of hypersonic and aerospace vehicle development is given. Methods of material choice for a hot and thermal protected structure is discussed.

This paper presents the theory of an insulation-radiation cooling method applicable to expandable hypersonic vehicles; two simple configurations, a sphere and a cylinder, are analyzed to illustrate this method.

The development of simulation codes for hypersonic flow computations is the pacing ilea in the definition of a reentry vehicule such as the European HERMES, in order to complement the experimental facilities which cannot cover the complete flight envelope.

A single, efficient, reliable emergency escape system is needed to provide, at an acceptable total cost, emergency escape capability throughout the entire mission envelope of hypersonic and orbital vehicles. Analysis and limited testing indicate that the Douglas Paracone emergency escape system will meet this requirement.

The refractories were being considered for the wing leading edges and the nose of a proposed hypersonic aircraft. The insulants were for application between the outer skins and the interior structure.*