Search results

The Howard Shuttering Contractors case throws considerable light on the importance which the tribunals attach to warnings before dismissing an employee. In this case the tribunal took great pains to interpret the intention of the parties to the different site agreements, and it came to the conclusion that the agreed procedure was not followed. One other matter, which must be particularly noted by employers, is that where a final warning is required, this final warning must be “a warning”, and not the actual dismissal. So that where, for example, three warnings are to be given, the third must be a “warning”. It is after the employee has misconducted himself thereafter that the employer may dismiss.

AT the beginning of October it was announced that the Pressed Steel Co. Ltd. were taking steps to form a subsidiary company to concentrate upon the design and manufacture of a new range of executive and light aircraft for the home and export markets. To this end, the whole of the share capital of Auster Aircraft Ltd. has been acquired and a technical and manufacturing liaison with F. G. Miles Ltd. has been established. The new company will be known as British Executive and General Aviation Ltd. or by the abbreviated form of BEAGLE. Rolls‐Royce Ltd. have taken part in discussions with the various companies involved with a view to producing a series of engines suitable for this type of aircraft and a licence agreement with Continental Motors Corp. has recently been signed.

A PHYSICIST addressing an informal gathering recently was asked by one of his audience if lie could put Einstein's relativity theory in a nutshell. The task of covering in one short article the whole realm of problems which arise in the aerodynamic design of an aeroplane to‐day, though not so exacting, is still formidable. Fortunately a learned scientific thesis on every aspect, even were space available, is undesirable; for I am sure it will be agreed that a too meticulous or detailed study of even a few of the problems would only obscure the main issue, which is to discuss our present ideas on aeroplane design from the aerodynamic point of view and to indicate the direction in which they are likely to lead us.

THE concept of an ‘all‐plastics’ airframe has been possible of achievement since the early 1940s but, apart from some special applications, such as radar and radio transparencies, bearings, fuel tanks, etc., the introduction of reinforced bonded materials has been extremely slow. Curiously, and despite the intense pressures of technological advances, the aircraft industry is conservative and many innovations which can be seen in retrospect to have been inevitable, have been held back for years until they have been forced on the designers by circumstances. Cases in point are the time taken to abandon the biplane to accept wing flaps and to adopt variable‐pitch propellers. Even the jet engine was, for a long time, squeezed into airframes of obviously unsuitable shape. Nevertheless, it seems surprising that it has taken some twenty years to bring the use of plastics for major airframe components to the stage of practical proof.

Typical performance data for combustion chambers with separate introduction of fuel and air have already been presented in FIG. 1. Comparison with FIG. 7, typical of one‐stream chambers, reveals some important differences. Firstly, the data are neither confined within the inflammability limits nor have their peak at the stoichiometric O.F.A.R.; the shift is usually towards the weak side. Secondly, the ratio of the maximum O.F.A.R. to minimum O.F.A.R. of a given curve may be many times the corresponding range of a one‐stream chamber. Thirdly, the curves do not all terminate at substantially the same value of combustion efficiency. Particularly the second of these features is of great practical importance, for, in gas turbines, combustion chambers are required to cope with a very wide range of O.F.A.R. and must maintain a high efficiency throughout this range. The possibility of designing for a wide O.F.A.R. range is one of the reasons for using a two‐stream in preference to a one‐stream chamber. Some of the design features influencing O.F.A.R. range will be discussed below.

IT has been a year of mixed fortunes for the British aircraft industry typified by several irritating disappointments, a number of resounding technical successes and an overall feeling that the outlook for the future is bright. During the early part of the year the final stages of the regrouping of the industry took place, so that now there are in existence two main airframe groups, Hawker Siddeley and the British Aircraft Corporation; two main engine groups, Rolls‐Royce and Bristol Siddeley; a single helicopter group, Westland Aircraft, and a number of smaller individual companies such as Handley Page, Short Brothers and Harland, Scottish Aviation, Alvis and Boulton Paul Aircraft. A notable addition to the fraternity of the smaller firms has been the recent formation of British Executive and General Aviation which incorporates Auster Aircraft and F. G. Miles Ltd. with the financial backing of the Pressed Steel Company.

This article is based upon a paper presented by Major Oliver Stewart to a meeting of The Historical Group of the Royal Aeronautical Society on March 19, 1962, just a few days after the last issue of Major Stewart's own monthly aeronautical journal ‘Aeronautics’ was published. Although some fifteen months have now elapsed since the original paper was presented, it has continuing relevance at this time as the British aeronautical press undergoes further changes. To mention but three examples, the journal ‘Airport and Airline Management’ ceased publication with its May I June 1962 issue, the English language edition of the French ‘Aviation and Space Magazine’ ceased publication with its April 1963 issue, and ‘Aircraft Production’ became a general production engineering journal as from the April 1963 issue. There can be few people better qualified to describe the changing scene of aeronautical journalism, for apart from his experience as a ferry pilot and single‐seat fighter pilot during the First World War and subsequently as an experimental and test pilot at Orfordness and Marilesham Heath, Major Stewart has been aeronautical correspondent of ‘The Morning Post’ (1926–37), ‘The Times’ (1939), ‘The Evening Standard’ (1940) and ‘The Manchester Guardian’ (1941–58). In addition, he was, of course, Editor of ‘Aeronautics’ from the time of its birth in 1939 until its demise last year.

Assisted high‐lift devices which are based on the removal or the addition of air jets from the flow over the wings may be classified as follows, in accordance with their method of operation:

IN the life of a man ten years is a comparatively short period, but in aeronautics it is an epoch.

The solution of the problem of estimating the take‐off distance to a height of 50 feet has to a certain extent been limited by the absence of a theoretical analysis of the airborne part of the take‐off manoeuvre. The three main physical quantities associated with the motion immediately after an aircraft leaves the ground are aircraft speed, the angle the flight path makes with the horizontal and the lift coefficient increment. This latter quantity is the lift coefficient in excess of that required for level flight at the unstick speed, and is produced when the pilot pulls the stick quickly back at take‐off. A linear theoretical analysis is obtained by assuming that variations of the physical quantities already mentioned are small enough for squares and higher powers of such variations to be neglected in comparison with the variations themselves. The results of the analysis depend on the solutions of a pair of ordinary simultaneous linear differential equations with constant coefficients. If the aircraft speed never falls below the unstick speed, the limiting values of the lift coefficient increment which define the safe range of take‐offs can be determined. By considering the mean value of the lift coefficient increment over the safe range of take‐offs it is possible to define a mean safe take‐off, and for such a take‐off, the mean safe airborne distance from the unstick point to a height of 50 feet can be estimated. The application of the theory as a means of estimating the take‐off performance of a bomber aircraft is given as an example at the end of this work.