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ONE of the many features that need careful consideration during the initial design stages of a modern cargo carrying aircraft is the adequate provision of suitable loading facilities. A commercial aircraft is only producing revenue when it is in the air carrying cargo and it is therefore essential that the greatest number of flying hours possible be achieved. Speed is one of the main factors in reducing costs to an airline operator, because it enables him to spread his fixed operating costs over a greater number of miles per hour. The efficiency of a freighter in the air, however, can be nullified by its ‘performance’ on the ground, for a 30 m.p.h. increase in cruising speed, for example, might well be outweighed by delays in loading and unloading the aircraft at its stopping places.

This paper presents a case study on the problem of loading air containers in air express carriers motivated from DHL and Air Hong Kong. The problem is to determine the containers to be loaded and the locations of the loaded containers in an aircraft while maintaining stability of the aircraft. The objective of the problem is to maximize the revenue obtained from delivering containers. We present an integer programming model to represent and optimally solve the problem. Computational experiments done on a number of randomly generated test instances show that the integer program can be a viable tool for generating loading plans in the companies since optimal or near-optimal solutions for the test instances are obtained within a reasonable amount of computation time.

By application of the analytical method to a wide range of current aircraft types an approximate form of the method is developed for the quick estimation of tail load maxima and associated torques during the checked manoeuvre and the same is also confirmed for the unchecked manoeuvre of Ref. (3). Numerical values of critical elevator actions to be associated with the airworthiness design case are considered and hence, from a comparison with the approximate method, the limitations of the present empirical approach given in British and American civil airworthiness regulations are brought to light.

IN aircraft construction, until about fifteen years ago, the customary static method of stressing generally also provided for an adequate fatigue strength. This does not now apply for various reasons (e.g. increased flight speeds, use of high‐strength materials with changed fatigue properties). It is, therefore, necessary to establish design rules which take account of more recent knowledge; which variables are to be specially considered, and what their importance is in a particular case, becomes clear from fatigue tests which, to a considerable extent, cater for the peculiar loading conditions of flight (service endurance tests or programme‐loading tests). The principle of these tests was established in the DVL (1938 to 1941) and it is now in general use in automobile design for determining the relation between fatigue strength and endurance (life function) as in many cases of service failures a very good agreement with these tests can be observed.

IN the year 1945 aircraft structural design had reached an advanced stage in this country, as judged by all previous standards. The needs of war and the vast expenditure on aircraft design and manufacture had unquestionably forced the pace of progress. On the other hand, war‐time conditions must inevitably have tended to produce an unbalanced growth. Expenditure of money and effort was accompanied by a no less drastic expenditure of technical capital, and really long‐term thinking was unavoidably put aside.

THE purpose of this paper is to examine the part that metal fatigue plays in the engineering of the helicopter, and to outline the methods used at present to estimate the safe fatigue life of the component parts of the helicopter.

A Discussion concerning the Use of Wind Tunnel Results and Flight Test Measurements in the Prediction of Aerodynamic Loads for Stressing Purposes in the Aerodynamics Department of the Weybridge Division of British Aircraft Corporation. The responsibility for the prediction and issue of aerodynamic loads for stressing purposes at the Weybridge Division of British Aircraft Corporation is carried by the Aerodynamics Department. The arguments for and against this arrangement are briefly examined. One of the main arguments in favour is the facility with which wind tunnel tests can be instigated and controlled. The use of wind tunnel tests specifically designed to give aerodynamic loading data and their relation to estimation using theoretical and semi‐empirical methods is fully discussed and illustrated. The confirmation of design estimates by full scale in‐flight load measurement is described and the usefulness of in‐flight measurements as a design tool on subsequent aircraft of a similar type is discussed.

The United States Air Force often provides effective airlift for cargo distribution, but is at times inefficient. This paper aims to address the under-utilization of military airlift cargo compartments that plagues the airlift system.

The authors examine seven techniques designed to increase cargo compartment utilization and increase airlift utilization rates. The techniques were applied through load planning software to 30 real-world movements consisting of 159 sorties. They then ran each post-technique movement through a modeled flight environment to obtain cycle movement data. The metrics gained from both the load planning software and the modeled environment were regressed to provide statistical understanding regarding how well each technique influenced cost savings.

The results showed a 24 per cent elimination of aircraft required and a savings of $14.5m. Extrapolation of the authors’ findings to four years of airlift mission data revealed an estimated annual savings of $1.6bn.

This research effort provides multiple options to improve the efficiency and effectiveness of military airlift.

Flight simulators are one of the noticeable breakthroughs in aerospace engineering. One of the main compartments of flight simulators is its control loading system (CLS). The CLS functions as a generator of virtual aerodynamic control-loads over control columns of a simulator. This paper aims to present the design of a high-fidelity six six degrees of freedom (6DOF) nonlinear CLS for the Boeing-747 aircraft simulator.

An introduction to CLS for flight motion simulators are first recapitulated. Afterward, the commanding devices are explained through schematics available in an engineering sense. This paper then presents in detail, the active control loading strategy and hardware design for the CLS, while also introducing the aerodynamic model structure. The satisfactory computer numerical simulations are presented before the paper ends up in concluding remarks.

The multiple input multiple output (MIMO) 6DOF nonlinear CLS for Boeing-747 flight simulator has been successfully developed. The outcome of computer simulations in real-time verifies practicality of the design strategy. The research presented in this paper could be a simple roadmap for prototyping high-fidelity 6DOF nonlinear CLS for flight motion simulators.

The available control architecture and hardware technologies cannot enable a high-fidelity load realization in a CLS. The existing research has not yet presented a 6DOF nonlinear MIMO CLS architecture along with the underlying controller setup for a high-fidelity load realization. In this paper, the design of a high-fidelity 6DOF nonlinear MIMO CLS for flight simulator of a large transport aircraft has been accomplished.

INTEREST in the fatigue of cabins of transport aircraft has increased considerably in the last year or so. Fatigue tests on a complete aircraft, undertaken as part of the Comet accident investigation, gave indications that the fatigue life of pressure cabins could be more critical than had generally been supposed.