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This paper aims to present a novel structural reliability analysis scheme with considering the structural strength degradation for the wing spar of a generic hypersonic aircraft to guarantee flight safety and structural reliability.

A logarithmic model with strength degradation for the wing spar is constructed, and a reliability model of the wing spar is established based on stress-strength interference theory and total probability theorem.

It is demonstrated that the proposed reliability analysis scheme can obtain more accurate structural reliability and failure results for the wing spar, and the strength degradation cannot be neglected. Furthermore, the obtained results will provide an important reference for the structural safety of hypersonic aircraft.

The proposed reliability analysis scheme has not implemented in actual flight, as all the simulations are conducted according to the actual experiment data.

The proposed reliability analysis scheme can solve the structural life problem of the wing spar for hypersonic aircraft and meet engineering practice requirements, and it also provides an important reference to guarantee the flight safety and structural reliability for hypersonic aircraft.

To describe the damage evolution more accurately, with consideration of strength degradation, flight dynamics and material characteristics of the hypersonic aircraft, the stress-strength interference method is first applied to analyze the structural reliability of the wing spar for the hypersonic aircraft. The proposed analysis scheme is implemented on the dynamic model of the hypersonic aircraft, and the simulation demonstrates that a more reasonable reliability result can be achieved.

As to different angles of attack and nonlinear problems caused by high temperatures in coexisting hypersonic aircraft, people mainly rely on fluid software for research but lack analysis of flow mechanisms. Owing to computational difficulties, few people use numerical algorithms to combine them for discussion. Hence, this study aims to make a deep inquiry into the laminar flow and heat transfer of compressible Newtonian fluid in hypersonic aircraft with small attack angles.

In this paper, on the basis of mass, momentum and energy conservation laws, the governing equations of the hypersonic boundary layer are established. Viscosity, specific heat capacity and thermal conductivity are considered nonlinear functions concerning temperature. In virtue of the MacCormack finite difference method, the stationary numerical solutions are solved directly, and the validity of the algorithm is verified.

The results demonstrate that at Mach number 5, compared to the 0° attack angle, the maximum temperature near-wall at the 3° attack angle increases by about 25%. An enjoyable phenomenon is discovered, where the position corresponding to the maximum wall shear force shifts back as the attack angle and Mach number increase. The relationship between the near-wall maximum temperature versus attack angle and Mach number is fitted through numerical calculation results.

Empirical formulas can be used to estimate heat transfer characteristics at small attack angles, which will guide the design of aircraft thermal protection systems.

SUMMARY The main overall problems associated with transparencies for manned supersonic and hypersonic aircraft are considered. Civil and military concepts are compared in relation to aircraft performance requirements and the reasons for the continuing need for optical transparencies are enumerated. Aircraft performance requirements and typical flight plans show the necessity for designing the transparencies to withstand a considerable range of environmental conditions in addition to the aerodynamic dictates in relation to size, position and shape. These conditions are listed and design feature considerations are discussed in some detail with particular accent on the thermal problems. Reference is made to certain organic and inorganic materials for the basic glazings and the problems associated with the ‘marrying’ of these materials with retaining frame members are discussed. Detail proposals are made for typical windscreen and canopy assemblies. Brief reference is made to the poor reliability shown by many transparencies in present‐day modern aircraft which indicates the need for revision of certain existing test requirements. The proposed new requirements will result in the development of new testing techniques although test factors might well be reduced. The paper concludes with a statement on the importance which is being given to the subject matter by the various bodies in the U.K. and the emphasis which should be placed on the need for the continuation of research and development work in this field.

The purpose of this paper is to attempt an aerospaceplane design with the objective of Low-Earth-Orbit-and-Return-to-Earth (LEOARTE) under the constraints of safety, low cost, reliability, low maintenance, aircraft-like operation and environmental compatibility. Along the same lines, a “sister” point-to-point flight on Earth Suborbital Aerospaceplane is proposed.

The LEOARTE aerospaceplane is based on a simple design, proven low risk technology, a small payload, an aerodynamic solution to re-entry heating, the high-speed phase of the outgoing flight taking place outside the atmosphere, a propulsion system comprising turbojet and rocket engines, an Air Collection and Enrichment System (ACES) and an appropriate mission profile.

It was found that a LEOARTE aerospaceplane design subject to the specified constraints with a cost as low as 950 United States Dollars (US$) per kilogram into Low Earth Orbit (LEO) might be feasible. As indicated by a case study, a LEOARTE aerospaceplane could lead, among other activities in space, to economically viable Space-Based Solar Power (SBSP). Its “sister” Suborbital aerospaceplane design could provide high-speed, point-to-point flights on the Earth.

The proposed LEOARTE aerospaceplane design renders space exploitation affordable and is much safer than ever before.

This paper provides an alternative approach to aerospaceplane design as a result of a new aerodynamically oriented Thermal Protection System (TPS) and a, perhaps, improved ACES. This approach might initiate widespread exploitation of space and offer a solution to the high-speed “air” transportation issue.

THE problem of providing engines suitable for high Mach number aircraft is a fascinating study which at the moment has only been taken to the stage where many solutions look feasible, thus the choice of engines for the different roles for which high Mach number aircraft may be used is still fairly wide open.

The purpose of this paper is to propose a new approach for aerodynamic parameter identification of hypersonic vehicles, which is based on Pigeon-inspired optimization (PIO) algorithm, with the objective of overcoming the disadvantages of traditional methods based on gradient such as New Raphson method, especially in noisy environment.

The model of hypersonic vehicles and PIO algorithm is established for aerodynamic parameter identification. Using the idea, identification problem will be converted into the optimization problem.

A new swarm optimization method, PIO algorithm is applied in this identification process. Experimental results demonstrated the robustness and effectiveness of the proposed method: it can guarantee accurate identification results in noisy environment without fussy calculation of sensitivity.

The new method developed in this paper can be easily applied to solve complex optimization problems when some traditional method is failed, and can afford the accurate hypersonic parameter for control rate design of hypersonic vehicles.

In this paper, the authors converted this identification problem into the optimization problem using the new swarm optimization method – PIO. This new approach is proved to be reasonable through simulation.

The transport system is fundamental to both meeting social needs and providing the lifeblood for the economy. In recent years, transport and especially the automotive sector has had to respond to increased competition and environmental concerns. Technological innovations in transport appear particularly important since they could provide competitive advantage for providers of transport technology and also address environmental issues. This article considers both short‐term and long‐term policy implications which emerge from analysis of national foresight studies in the area of transport.

DURING the first forty years or so of the history of manned flight, the application of aerodynamics was confined largely to subsonic speeds and to one basic aircraft shape. Since the end of the Second World War the aerodynamic domain has expanded in spectacular fashion in terms of speed and shape until at the present time ‘conventional’ manned aircraft are penetrating into the realms of hypersonic velocities and the satellite vehicle has brought with it aerodynamic problems at what must surely be the near‐ultimate speed range for the technology. Nor are these advances confined to high‐speed aerodynamics: they include radically new approaches to low‐speed problems, particularly those arising from take‐off and landing manoeuvres.

THERE have been various suggestions that the return of man from his trips of exploration into space may best be effected by glider. The design of such an unusual form of aircraft will present many unusual and difficult problems, and here we shall merely be content to remark upon those which fall into the category of stability and control.

The purpose of the paper is to design a robust control system for a generic hypersonic vehicle which includes dynamic nonlinear, open loop unstable and parametric uncertainties.

For a complex longitudinal model of a generic hypersonic vehicle which includes dynamic nonlinear, open loop unstable and parametric uncertainties, a nonlinear dynamic inverse (NDI) approach combined with proportional differential (PD) control is used to design a strong robust control system to deal with the sensitivity to changes of atmosphere condition. In this way, a simple genetic algorithm is used to search a group of parameters of the control system to satisfy the specific performance indices. Then parametric uncertainties are considered to verify the robustness of the control system.

The PD hypersonic vehicle control system using NDI approach can satisfy the specific flight performance. And it has strong robustness under the parametric uncertainties.

The paper fulfills a complete process of the nonlinear control system design for a generic hypersonic vehicle. And, the simulation results show the efficiency and robustness of the control system.