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Since the motivation for research in the civil transport field is mainly to improve the aircraft's economics, and since active control technology (ACT) offers more in terms of direct operating costs than do many other areas, the functions of relaxed stability, manoeuvre load alleviation and gust load alleviation are receiving considerable attention. Companies are actively pursuing programmes which promise major gains in efficiency, one of these involving a British Aerospace One‐Eleven which will be equipped with ACT packages. Intially, the two systems of load alleviation and an active elevator will be kept separate for research purposes with the objective of determining how much ACT technology can be designed into future commercial aircraft and what benefits can be derived from applying it to existing types.

Reviews the evolution of British Aerospace’s wing production facilities at Chester and Filton in the UK and on the design of the wings for the Airbus series of aircraft, from the first set of wings designed for the A300 in 1971 through to the A340‐500 and 600 and the A3XX. Reports on the design of the completely new wing for the A320 which was the first to incorporate fly‐by‐wire and other technologies. Discusses the design of load alleviation for defined manoeuvre and gust cases and the impact of a change in the airworthiness design case requirements on the design of the wing for the A321 and subsequent aircraft. Finally, the article examines the fully automated parts store at the British Aerospace Wing Centre at Filton.

This study aims to predict dynamic responses of aileron and spoiler control surfaces in subsonic flight via the use of surrogate models. The prepared reduced order models prove useful when quick estimations for a large number of variations are required.

The linear frequency domain (LFD) method was used for the simulation study. Each surrogate contained a database of 100 control surface dynamic responses over a spectrum of 200 harmonics computed with LFD. To interpolate new results, the DLR surrogate modelling toolbox, SMARTy, was used. The database’s samples were prepared in a Halton sequence, making interpolation reliable. The surrogate’s parameter space was the Mach number, Reynold’s number, angle of attack, control surface deflection angle and the control surface chord length.

The LFD method proved effective for the mentioned purpose: the surrogates were accurate, up to 15% of relative error, in reproducing dynamic responses of aileron and spoiler deflections at low speed, within the limitations of flow field linearity, as well as surrogate prediction capability. The restrictions of the surrogate, and the reasoning thereof, are also presented in detail in the study. Future load alleviation studies are a potential of the findings here.

LFD is an innovative technique for load prediction and alleviation studies. This paper provides a reference for engineers wishing to use the method for the two mentioned control surfaces, or the like.

Held at the NEC Birmingham, the Aerospace Technology Exhibition and Conference was sponsored by the Aerospace Industries Division of the Institution of Mechanical Engineers together with the Institutions of Electrical Engineers and Electronic and Radio Engineers. It attracted papers on a variety of subjects and gave companies the opportunity to show a range of products, many of which were related to safety matters or maintenance programmes.

EUROPEAN aerospace was well to the fore at the Show, with first appearances of the A320, Fokker 100 and BAe 146–300. Few large US aircraft were present although the executive jet market was well represented with products from both sides of the Atlantic. Potential developments were featured in many areas, all of which should be realised in the next few years. Progress of the flight trials of the Airbus Industrie A320 was detailed with three of the four aircraft in the programme now flying. The first of these is exploring all the critical flight conditions. The normal operating envelope was covered on the first flight; from 80 knots to 381 knots/0.89 M and a cg range up to 46% aft cg. Handling qualities have now been explored over the full flight envelope, with the protection devices working as predicted and buffet limits better than forecast. Major tasks have included stall identification and handling qualities at aft cg as well as flutter tests with and without the load alleviation function. The second A320 has the primary tasks of dealing with the development and checking of the systems, emphasis on the third is placed on flight control and computing and the fourth aircraft will be undertaking performance trials.

THE highly complex character of the gust‐load problem and the lack of knowledge of gust structure have led to the general use of gust‐strength criteria for aeroplane wings that are based on the concept of a “sharp‐edged” gust in which the aerodynamic phenomena are assumed to obey the laws of steady flow.

The purpose of this paper is to find an omnidirectional robust gust response stabilization (GRS) scheme with anti-disturbance and state-limited features.

Disturbance observer and barrier Lyapunov techniques, which can, respectively, estimate the lumped disturbances of the dynamic system in real-time and ensure the middle states within some prescribed ranges according to some flight safety indexes.

In the existing literature, almost all of the GRS controllers are either only for the longitudinal dynamics or only for the latitudinal dynamics. Few studies have considered the gust response alleviation problem with omnidirectional wind disturbance and full aircraft model.

This paper proposes a fresh scheme to deal with a more holistic GRS problem; the disturbance observer based (DOB) barrier Lyapunov backstepping longitudinal controller has been put forward; DOB nonlinear dynamic inversion to handle the multi-input-multi-output lateral dynamics; and to closely connect the two loops of the latitudinal dynamics, a manipulating variable conversion method is proposed.

IN March Air France becomes the first airline to take delivery of an Airbus A320. Two more will follow in April and a fourth in September with all of the 25 ordered gradually replacing the earlier Boeing 727's over the next few years. British Airways will also receive its first A320 during March and others will be delivered during the year.