In the note “Aerodynamically induced vibration in coolers”, by D. G. Mabey (pp 876-7, December 1965 Journal), the results of Grotz and Arnold concerning the frequency of the Karman vortex streets in tube banks, such as in heat exchangers, are mentioned, as is also the law of the linear relation between f(T—d)/V and (2T-L)/d, as found by Putnam, where

f frequency of vortex shedding

T transverse distance

L longitudinal distance between tubes

d outer diameter of tube

V mean stream velocity based on minimum flow area between the tubes

This linear relation has no theoretical justification and cannot be accurate, as is admitted by the author cited. A further investigation on a theoretical basis seems to be necessary.

Summary:—There is no doubt of the need for strong central planning of aeronautical research and development as advocated by the Post-Plowden Working Party of the Royal Aeronautical Society (pp. 391-392 June 1967 “Journal“).

But there are many other problems in the efficient use of aerospace resources which are equally in need of attention by the Society. Among the most important are:

1. The complementary role of improved industrial and project management.

2. The need to deal separately with the distinct problems of Defence, Civil Aviation and Space—in particular the improvement of Defence procurement methods.

3. The need to discover the correct commercial and engineering bases (as distinct from political bases) for European collaboration.

4. The need to complement the work of a strong planning organisation by providing facilities for high-level and informed technical debate, wherever possible in public.

The Aviation Group of the Ministry of Technology (formerly the Ministry of Aviation) is responsible for spending a large part of the country's defence budget, both in research and development on the one hand and production or procurement on the other. In addition, it has responsibilities in many non-defence fields, mainly, but not exclusively, in aerospace.

Few developments have been carried out entirely within the Ministry's own Establishments; almost all have required continuous co-operation between the Ministry and Industry. In the past the methods of management and collaboration and the relative responsibilities of the Ministry and Industry have varied with time, with the type of equipment to be developed, with the size of the development project and so on. But over the past ten years there has been a growing awareness of the need to put some system into the complex business of translating a requirement into a specification and a specification into a product within reasonable bounds of time and cost.

The technical note by Dr. Alexander implies that hovercraft jet performance might be better than simple theory predicts for values of 1/x greater than 4. The experimental points used to compare with theory were obtained at the beginning of hovercraft development, but subsequently a number of British and American reports have been issued whose data can be interpreted to give points for comparison with theory. These results show that the simple theory overestimates the performance of the jet.

It would not, perhaps, be an exaggeration to say that aeronautics and space technology represent the most dynamic, progressive and exciting field of modern knowledge, where many bold dreams of yesterday are rapidly becoming the spectacular realities of today and tomorrow. Never before, and in no other field, has man learned so much and so profoundly in such a short space of time as he has here during the past ten years or so. This explosion of aerospace knowledge has brought forward and established new dimensions and criteria of national defence, international relations, military strategy, socio-political thought, economics, commerce, etc, and affects everyone’s life in one way or another.

Following a brief description of the basic radio aids and the terminology used, the paper discusses in some detail the differences between the original British and American approaches to all-weather landing; the different types of equipment resulting from these two approaches are broadly described. The mixing of ideas which occurred at the IATA Conference at Lucerne in 1963 and the more recent tendency towards a blending of British and American ideas are then discussed, and some predictions are made as to the form of the ultimate all-weather landing system. Certain Australian contributions to display research and the simulation of low visibility in flight are mentioned in context.

The experimental methods in current use for the determination of the dynamic properties of an arbitrary finite-freedom system are based on restrictive assumptions which may often be of questionable validity. The most common assumption is that the damping matrix can be reduced to a diagonal form by a congruent transformation using the modal matrix of the undamped system. Further, the damping is normally assumed to be hysteretic, or light if viscous.

Bishop and Gladwell give an excellent account of the theoretical background of the present experimental techniques. These can be divided into three groups:

• 1. The method of Kennedy and Pancu which obtains experimentally the complex receptance of the system and extracts its dynamic properties from vectorial plots.

• 2. The method of Trail-Nash and Asher which is based on the experimental determination of the in-phase response of the system and requires computation to be incorporated with the experimental procedure.

The nature of handling criteria and their uses in relation to the prediction of aircraft handling characteristics are discussed. A brief history is given of the development of ideas on handling, and a survey is made of criteria for modern aircraft, looking particularly at the physical factors affecting the pilot, as an indication of the basis of the criteria. The novel handling features arising with new aircraft species like slender wings and VTOL are considered. The scope of flight simulators and variable stability aircraft for systematic study of handling is discussed and the potentialities of theoretical study by means of servo analysis techniques considered. Finally, possible lines of development in relation to the assessment of aircraft handling characteristics are suggested.

The basic theory of the compressible non-swirling rotational flows through ducts with varying hub radii, associated with the concept of actuator discs, is described. The problem is simplified by considering a single-parameter in the radial velocity profile. Particular attention is given to the combined effects of the taper of inside walls and also of compressibility on the radial velocity and the axial velocity profile. The derived ordinary differential equation with non-homogeneous terms can be reduced to the well-known formula of classical actuator disc theories for the cylindrical passage. A numerical example is also presented.

The direct problem of aerodynamics (profile of the aerofoil is given—calculate the aerodynamic characteristics) has been studied for thin aerofoils with small camber. Given the undisturbed stream function

V, ω, α being the constant velocity, vorticity and angle of incidence respectively, the pressure distribution, lift coefficient and pitching moment have been calculated for a general profile.

From the very start of aviation a suitable engine has been the basic pre-requisite for successful flight.

The first known Swedish proposal for a heavier-than-air flying machine was made in 1716 by the scientist and philosopher Emanuel Swedenborg. A steam engine, invented by him in 1714, was to provide the propulsion. His superior, “Royal Mechanicus” Christoffer Polhem, opposed the idea, and the project was abandoned without any attempt being made. More than 150 years later, in 1877, another Swede—Carl Rickard Nyberg, well-known inventor of the blow-lamp and other gas-producing devices using liquid fuel—presented a design for a helicopter and 20 years later still, for a steam-engine-driven aeroplane. The engine weight problem was to be solved by using a light tubular steam boiler, invented by him. Several prototypes were produced during the years 1899 to 1910 without being really flyable since the steam engine gave only 10 hp compared with the estimated 40 hp required.

Management Education in the Air Corporations is based largely on the Air Transport Staff College, East Burnham. This was originally founded by BEA in 1960; BOAC had a similar establishment at Dormy House, Sunningdale, from March 1963. The two Corporations now share East Burnham on an alternate monthly basis. Up to 35 students can be accommodated.

In 1957 the successful launching of the first artificial earth satellite had little immediate effect on the technical activities of the Aerospace Industry of the European countries. It was some years before various countries in Europe either singly or collectively allocated significant funds from their national budgets to allow any real research and development work to begin. In Britain, for example, it was only with the cancellation of Blue Streak in 1960 that the question of determining some sort of national policy in space activity was really brought into focus.

Work on the finite element analysis of flat plates in bending has been directed towards elements which satisfy kinematic conditions between the adjacent elements in conjunction with the theorem of minimum potential energy, eg Argyris, Bazeley et al, Clough and Veubeke.

The purpose of this Note is to provide the main details of a triangular element which satisfies equilibrium conditions between the adjacent elements and which is used in conjunction with the complementary energy principle. The bending moments vary linearly within the element and use is made in the derivation of the analogy (see eg Southwell, Fox, Fung and Morley that exists between problems of plane stress and plate bending. In particular, many of the present details are taken directly from the plane stress analysis of Veubeke who, along with Argyris, considers a displacement triangular element with linearly varying strain.

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.

I would first like to thank the Royal Aeronautical Society for inviting Entwicklungsring Süd to give this lecture on the development work on vertical take-off aircraft. The Southern Germany Development Group—Entwicklungsring Süd—the abbreviation of which is EWR—was founded at the beginning of 1959 for the purpose of developing a vertical take-off and landing strike-fighter, the VJ 101, and was an association of the three firms: Bölkow-Entwicklungen KG, Ernst Heinkel Flugzeugbau GmbH und Messerschmitt AG. Heinkel has recently left the association and joined Vereinigte Flugtechnische Werke (VFW), Bremen. The work is now carried on by the remaining two firms, Bölkow and Messerschmitt. Since July 1965 EWR has the form of GmbH (Ltd).

At the outset, I must make it quite clear that any views or opinions expressed are my own and are not necessarily those of either British European Airways or the Flight Safety Committee.

In this paper, I have attempted to discuss some of the problems which face those whose task is to obtain and to disseminate safety information. At the end, I have posed a number of questions which I believe are relevant and should be posed, and which Harold Caplan will take up in his subsequent discussion of the legal problems.

Air Safety is essentially the prevention of accidents by minimising the risk of encountering foreseeable hazards and the consequences of unforeseen situations. Thus the dissemination of air safety information is simply the spreading of accident prevention material. It is undoubtedly best achieved by a sharing among all concerned of the lessons learned from their incident and accident experience. This activity is one that has to be shared by operators, flight and ground crew, air traffic control, the designers and makers of aircraft, engines and equipment, and regulatory authorities.