I Feel highly honoured at having been asked to deliver this inaugural lecture as a prelude to the bi-annual series of Memorial Lectures on the development of Civil Aviation in South Africa. This lecture will be devoted to the man—Major Allister Macintosh Miller.

Much has come about in the field of Civil Aviation since the days I am going to speak about. Space and time have been telescoped. Colossal strides have been made. In this hall tonight I see a number of persons who, like myself, are able to make the comparison between the civil aircraft of vintage 1919 and the civil aircraft of today.

The success of the TUBA plate elements, has not only engendered the development of the SHEBA elements but has also lead, nolens volens, to the consideration of folded plate structures (Faltwerke), which are of considerable practical importance. A little thought shows that a consistent theory of such systems requires that the kinematic representation or interpolation rule of the membrane state is identical to that for the bending state laid down in the TUBA analysis. Moreover, the membrane modes must be effectively the same as the ones adopted for the SHEBA element.

Measurements of skin friction were made with a set of rectangular mouthed pitot tubes of constant thickness ratio. The results gave a unique calibration between skin friction and pressure recorded by the tube when plotted after the method of Preston it the outside thickness is taken as the representative length. The calibration curve differs from that for circular Preston tubes when the effective centre of the pitot mouth lies within the sublayer.

In the past aircraft loading has only had a minimal effect on terminal design. In principle the only preference was that aircraft should be parked as near to the terminal building as possible so that load was carried over the shortest possible distance.

There are many who have stated that the arrival of the very large aeroplane is going to cause massive congestion in terminal buildings. This is not really the case, as the very large aircraft themselves will not increase the market. The only effect their introduction has is to bring the traffic into terminals in larger clumps.

Although a numerical solution of the turbulent boundary-layer equations has been achieved by Mellor and Gibson for equilibrium layers, there are many occasions on which it is desirable to have closed-form expressions representing the velocity profile. Probably the best known and most widely used representation of both equilibrium and non-equilibrium layers is that of Coles. However, when velocity profiles are examined in detail it becomes apparent that considerable care is necessary in applying Coles's formulation, and it seems to be worthwhile to draw attention to some of the errors and inconsistencies which may arise if care is not exercised. This will be done mainly by the consideration of experimental data. In the work on constant pressure layers, emphasis tends to fall heavily on the author's own data previously reported in ref. 1, because the details of the measurements are readily available; other experimental work is introduced where the required values can be obtained easily from the published papers.

This paper is a reaction paper, in the sense that the author has recently been concerned, both as an economist and a technological forecaster, with looking at the total economic consequences of space activity. I describe it as a reaction paper because, as a hopefully “professional” worker, I am not amused at the methods used to evaluate proposals in this particular field, and, if one is restricted solely to the normal, customary, accepted criteria of economic reasoning, it is impossible not to react violently to the near confusion of arguments and decision-taking mechanisms in this subject.

I intend to speak briefly on three aspects of Project Management in the amplification of what Mr. Williamson has just said. Members of the audience who have attended lectures at this Society and elsewhere before, will, I am sure, recognise some of the Figures and I should not like it to be thought that I am presenting new or original ideas.

Turning to the control cycle that we at Hunting Engineering Ltd have been using now for a number of years, let me say that we believe that projects lasting two years or more need to be reviewed and re-cast, if necessary, at least every month. We have, therefore, evolved a four week management cycle and Figs. 1-5 explain our modus operandi. Programme re-casting is done at what we call the Management Decisions Meeting (Fig. 1). This takes place at the second week of the four week cycle. The efficacy of management decisions is tested by network re-running on the computer during the third week of the cycle, and on the assumption that the decisions meet the projects target date requirement the PERT time predictions resulting from these re-runs are issued during week three.

Exact solutions for certain types of non-linear systems where the non-linearity is symmetrical, that is to say, gravitational effects have been ignored, and damping is absent, are given by Den Hartog and Mikina. The algebra involved in these solutions is somewhat cumbersome and inconvenient to apply. A numerical method is given by Stormer but the computation is tedious without the use of a digital computer. The method employed by Lourie and Tchekmarev is commendable by virtue of its simplicity.

The phenomenon of a jet emerging tangentially to a wall and flowing along the surface of the wall has long been known as a wall jet. Plane and curved wall jets have been investigated by many researchers in the past. In spite of many investigations in this field, a reasonably complete understanding of the curvature effects on the turbulent wall jet has not been achieved. This investigation, therefore, was intended to serve as a complementary study of curvature effects. Experiments were performed with a two-dimensional turbulent jet flow over a plane surface and over circular convex and concave surfaces of various radii in still air. The study was limited to the mean properties of the flow and was not concerned with the momentum loss on the surface.

The Chairman said that the main object of the Symposium was to present the various facets of technological education as they exist today and as they seem likely to develop, having regard to those factors which were likely to influence technological education in the foreseeable future.

Inevitably there would be some bias towards the training of men and women for the aeronautical industry but this should not adversely affect the value of the discussions, for much of what applied to the aeronautical industry applied equally well to other engineering concerns.

Determination of the cross-sectional dimensions of panels of least weight typically follows the procedure set out by D. J. Farrar in this JOURNAL 20 years ago. Farrar made the assumption that for panels of least weight the flexural and local instability stresses were coincident. Using this he investigated the Z-section stringer-skin combination and later, using the same method, E. J. Catchpole studied the panel having unflanged integral stiffeners. In both cases the panel is treated as a wide strut, i.e. the flexural buckling load was taken to be the Euler buckling load, no account being taken of the effect of edge restraint.

I am defining the airport facilities as the strength of its pavements and the sophistication of its passenger and baggage loading and aircraft handling provisions.

To illustrate the effect of pavement strength on design, I have taken two representative sizes of aircraft, 50 000 lb (23 Mg) and 300 000 lb (136 Mg) AUW, and shown in Fig. 1 the effect on undercarriage volume of meeting various values of load classification number (LCN) with appropriate variations of tyre pressure and wheel spacing. The smaller machine has twin wheels while the larger has a four-wheel, twin-tandem bogie. The advantage to the designer of being able to work to a high LCN lies not only in the reduced undercarriage stowage volume, but undercarriage weight itself is saved if the wheels can be closely grouped together.

Although the past year cannot be classed as an outstanding one, nevertheless, there are some items which are worthy of noting and recording. The number of Fellows elected was the largest ever elected in one year, and the total number of members increased steadily if not spectacularly. It is of much concern to the Council that the number of Graduates and Students diminishes, and in the oncoming year efforts will be made to counteract this tendency.

A Joint Policy Committee has been formed with the Institution of Mechanical Engineers and Institution of Production Engineers to investigate all possibilities of cooperation in establishing joint policies and activities and even administration. At present, the Committee is investigating areas of such co-operation.

In a recent discussion on measurements made by Quarmby in fully-developed turbulent flow in concentric annuli, Quarmby has made several statements which are incorrect and need to be clarified.

Quarmby states that the pitot displacement corrections measured by MacMillan are those solely due to the shear and that they do not take account of the effect due to the presence of the wall. This is not so. Fig. 9 of MacMillan's original paper shows the total displacement effect. It is this total displacement effect which was used in my paper on the calibration of Preston tubes to relate the calibration curve to the inner-law velocity distribution. It is quite obvious that a Preston tube will be influenced both by shear as well as the wall and it would have been pointless to attempt to correlate its calibration with the velocity distribution using pitot displacement corrections unless these corrections included the rather important influence of the wall.

The transfer matrix method of vibration analysis is widely used for the calculation of the natural frequencies of turbo-generator rotors, and of propeller blades, axial compressor blades, turbine blades, and helicopter rotors. A comprehensive account of the method has been given by Pestel and Leckie. The basis of the method is to deine a state vector, which gives all the generalised displacements and forces at a given cross-section of the system. The state vector at one cross-section is then related to the state vector at a neighbouring cross-section by means of a transfer matrix. It is found that, by a suitable choice of the order and signs of the elements of the state vector, the transfer matrix can in many cases be made symmetrical about the secondary diagonal; that is the diagonal running from the top right corner to the bottom left corner of the matrix and is also often called the “cross diagonal”.