The main contribution of psychology to the design of displays up to the present time has been in advising on detailed points of design. It is suggested that there are three areas in which psychology can make a useful contribution; these are

(a) in stating the basic characteristics of the human operator, particularly the working of the perceptual mechanism,

(b) in stating the effect of environmental conditions on performance, and

(c) in assessing the information required and in advising on man's rôle in the system.

It is my very great honour to be asked as an operator to cover the Bell 212s part in the story of IFR operation of medium helicopters.

None of us should forget that two great British companies have for years been blazing a trail in the IFR operation of two helicopters, the S-61 and the Wessex 60, and I can only assume that it was because Irish Helicopters was, I understand, the first operator to put the CAA approved Bell 212/IFR into operation that the privilege of giving this talk has come my way, and I speak humbly and mindful of the invaluable efforts of others before us.

The Conventional method of assessing the direct costs or the aircraft type costs on a passenger mile or ton mile basis does not necessarily give a sufficient indication of the economic merit of a particular type of transport aircraft. It can be misleading when comparing aircraft of widely different design, and it does not indicate the best routes for effective airline exploitation.

The profit margin in relation to the fundamental cost or investment unit of the individual airline must be the ultimate yardstick of transport aircraft selection and this is here analysed with a view to providing further insight into the optimum conditions for potential profits. This study of the subject draws attention to the primary factors involved and suggests a criterion which can be simplified into a form valid for most airline economies.

Improvements made to the aerodynamic characteristics of the wing of the Avro CF-100 Mark 5 aircraft are discussed. Modifications to the wing included increase in aspect ratio, addition of vortex generators, and deflection of trailing edge plain flaps. The effect of flap deflection and addition of vortex generators on the aerodynamic characteristics of the wing are shown to be closely associated with interaction of the upper surface shock wave with the boundary layer. Performance gains were demonstrated at high subsonic speeds at high altitudes. Vortex generators improved the buffet boundary, whereas flap deflection both increased aircraft ceiling and improved buffet boundary.

The Important characteristics of the turbulent velocity profile of a plain concentric annulus and some of the methods of correlating the velocity distribution are briefly reviewed. The average velocities in an annular section are examined and some experimental data is correlated by a modified power law.

In 1962 the passenger fatal accident rate was less than one passenger fatality per 100 million passenger miles. This is a figure which can be used to demonstrate the safety of flying relative to other forms of transport.

I am not going to discuss the merits of the criterion of “passenger miles.” Whatever one says about it the rate achieved last year does demonstrate a notable improvement on the pioneer days of aviation when the airline passenger achieved a reputation of daring by accepting the risks then present.

Work on rocket propulsion was begun by the de Havilland Engine Co. in 1946, almost exactly a year after the end of the Second World War. For about the first year activities were confined largely to a general appreciation of rocket problems and techniques and to an assessment of the experience which had been obtained elsewhere. At that time “elsewhere” meant almost exclusively Germany, from where many technical reports were then becoming available.

In 1946 the policy in this country regarding guided weapons was, to say the least, obscure and the part which the liquid propellant rocket engine was to play in that field, even more obscure. It was not surprising, therefore, that the de Havilland Engine Co., being already well established in the field of aircraft propulsion, should very soon tend to concentrate its rocket propulsion efforts to manned aircraft applications. They were encouraged in this policy by the successful German use of the Me. 163 and of rocket take-off units fitted to the He.lll, Ju.88 and other aircraft. In particular, it was foreseen that the defence requirements of the United Kingdom might necessitate at an early date the use of a fast climbing rocket-propelled fighter.

The purpose of this paper is to attempt a broad review of some of the factors that influence the economic development of a country and to illustrate in general terms the importance and the application of airborne survey techniques, as a means of collecting the information on which any sound development must be based.

The industrial and agricultural revolution that is now taking place on a world-wide scale demands a completely new approach to the problem of economic development. When economic development was slow and confined to small areas it was sufficient perhaps to base that development on limited information. Today, however, the pace is quickening every year, but the speed with which we are obtaining the information, on which such development must be based, is lagging behind.

Why is the present position different from any other epoch in world history? The main cause is the industrial revolution, which has produced rapid means of communication, by air and by radio. The Twentieth Century now lives literally as neighbour to the Stone Age.

A further element for the Matrix Displacement method discussed in the author’s Main Lecture was a parallelogram or arbitrary anisotropy under plane stress. As for the other elements analysed in the preceding technical notes of this series, we assign to the parallelogram a linear variation of the strain along the edges. This is a more general specification of the strain pattern than for the parallelogram in ref. 2. Consequently, it is necessary to introduce additional nodal points in order to account for the increased number of kinematic freedoms. In the present case eight nodal points are provided as against four in the original model. The procedure is best understood in

I feel greatly honoured having been invited to deliver the Second Handley Page Memorial Lecture and, indeed, grateful for the opportunity to pay tribute to a great Englishman and aeronautical pioneer, who for 40 years was my personal friend and, for over 30, my Chief. As no other man, he has decisively influenced the course of my life.

A Discussion on the Relationships between Government and Aeronautics was held at the Society on 4th November 1965 with the President, Sir George Gardner, KBE, CB, HonDSc, FRAeS, in the Chair. Short introductory papers were given by Mr. Denis W. G. L. Hayiland, General Robert Lecamus and Brigadier General Ake Sunden. Introducing these principal speakers Sir George said how fortunate the Society was to have persuaded three such eminent people to open this Discussion; they were particularly grateful to their French and Swedish colleagues. General Sunden had graduated as an engineer and had been a pilot since 1934. He had served in a number of commands and had been a flying instructor and a test pilot. He was now a member of the Board and Director of Aircraft, Royal Swedish Air Force Board, which included responsibility for aircraft, armament, aero engines, airborne electronics and test flying.

General Lecamus was also an engineer and a pilot; he had served as an engine specialist in various duties, including three years as Head of the Engine Test Section at the French Test Flying Centre at Bretigny. In 1948 he had joined Direction Technique des Industriel Aéronautiques (DTIA) (which later became DTCA—Direction Technique des Constructions Aéronautique) as Deputy Chief of the Development Department and later had served as Chief of Inspection Services in Toulouse for the South West of France. He was now Director of DTCA.

Mr. Haviland had served throughout the 1939-45 War in the Army but he also had learned to fly. After the War he had been Principal, Control Office for Germany and Austria, becoming Assistant Secretary; in 1951 he transferred to the Ministry of Supply becoming Under Secretary, and from 1959-64 was Deputy Secretary, Ministry of Aviation. In 1964 he had joined Industry and was now Chairman and Managing Director of Staveley Industries Ltd.

In preparation for the wind tunnel testing of a series of aerodynamic research models a strain-gauged balance was sought which could be successfully made without the use of sophisticated tools. The principal requirements which influenced the design of the balance were:

1. (a) It must enable lift, drag and pitching moment to be measured.

2. (b) Deformation of the balance under the aerodynamic loads to be small.

3. (c) Use of only basic workshop tools.

4. (d) Short manufacturing time.

Further, the models were to be sting mounted at one end of the balance with their span vertical. The other end of the balance was to be rigidly fixed to a supporting stand which would be mounted on the wind tunnel turntable to permit incidence variation (Fig. 5).

This paper contains nothing new to airline people. It is not an original contribution. For some time I had been under the impression that the ideas we use and the troubles we have in the airline business were clearly understood by technical people outside the airlines. Recently, however, I have been surprised to discover that this is not so and this fact is the excuse for the shape of this lecture. So I am not talking to airline people but for them. If, when you have heard me, you have heard nothing you did not know, I shall be happy.

The purpose of this note is to present some recently acquired data showing the effects of variations in the open area of slotted liners on the pressures on a twodimensional aerofoil at sonic speed in the 36 inch X 14 inch transonic wind tunnel at the NPL. The basic slotted liners for this tunnel have eleven longitudinal slots, giving an open-area ratio (σ) of 0.091. Other slot openings are obtained by closing appropriate slots with “Sellotape.” Nine values of σ ranging from 0 to 0.091, were used in this investigation. A wall static-pressure orifice, sufficiently far upstream of the model to be unaffected by its presence (3-6 chords), was used as a reference pressure for tunnel speed. The relationship between the Mach number given by this reference pressure and the true tunnel Mach number (M0), at the model location, was obtained by careful calibration.

Measurements of cylinder drag in two-dimensional flow are readily available. In contrast, drag data for other cylinder configurations in which the flow is not strictly two-dimensional, for example free-ended cylinders or cylinders joined to a plane wall, is less plentiful. Some results for the former case have been given by Wiesels-berger and others, obtained at Gottingen and NPL, have been presented by Goldstein.

This note discusses some preliminary drag measurements made for turbulent flow about circular cylinders which were joined to plane parallel walls at each end. Such configurations appear repeatedly in practice. The justification for applying the classical free-ended cylinder data to this problem is slight since, in this case, flow may occur round the ends of the cylinder from the high pressure region upstream to the low pressure wake.

Until recently it was believed that Sir George Cayley's note-books had been lost. In 1927 Mr. J. E. Hodgson, the Honorary Librarian of the Society, learnt that a quantity of miscellaneous manuscript papers were in existence in the home of the Cayley family, and permission was obtained to sort out from such papers matter bearing on Cayley's aeronautical and other engineering or technical labours. Among them was the Note-book, which will shortly be published in full by the Newcomen Society, by kind permission of Sir Kenelm Cayley.