In the first contribution to “Looking Ahead in Aeronautics” Dr. Küchemann writes “The task of viewing the prospects over a whole century may be regarded as being at once impossible, presumptuous and not without a touch of the absurd”, which lies close to the first response of the present author. But on reflection, the very impossibility of reliable prediction a century ahead surely stands to change the tune somewhat. Over this large time-scale, bold flights of fancy into the unknown must take equal place with cautious realism and an author may presume to feel released from some at least of his usual conditioned restraints. In turn, yielding of constraint strengthens the writer's arm, until, not without a certain sense of trepidation, one is at length tempted to plunge into the guessing pool along with a goodly company of fellow men.

Since this is a Tizard Memorial Lecture, I think it is appropriate that I should tell you something about Operational Research in the Royal Air Force as it is carried on today. The RAF has a great tradition of actively using operational research to promote the efficiency of the Service and it was Sir Henry Tizard who initiated this tradition and sustained it until it was well established. Indeed, he was responsible for the much wider application of science to air warfare, but I am not attempting to cover the wider field in this lecture.

Before I begin to generalise about the RAF, let me make a generalisation about mankind and us islanders. All men are escapists by nature. What distinguishes islanders from all other men is that they are the progeny of active escapism. In the legends of antiquity these “Islands of the West” in which we live were the “Isles of the Blest”. Remote continentals longed to escape hither. That is something we tend to forget—not without reason nowadays!—although the process still goes on, in darker colours now. Aviation has become the most general and the most active form of escapism. It is essentially transcendental !

Structural testing has always been an art as well as a science but never more so than at present. Even though knowledge in relation to design and stressing has increased, testing is still a vital feature. This increase in knowledge has been accompanied by more complex problems particularly in relation to the need for environmental testing with the advent of supersonic and hypersonic aircraft, VTOL aircraft, rockets, guided missiles and space vehicles.

Considerable effort has been extended over the past years in adapting the matrix displacement method to the specific problems of thin shells under membrane and bending action and developing suitable elements of varying sophistication. Some of the difficulties arising in the process of idealisation were reviewed in ref. 1. For example, simple considerations show that a representation of a shell by polyhedron surfaces may lead to serious errors, especially in the presence of pronounced bending and so-called boundary-layer effects. For this and other reasons it appears imperative to allow for the curvature of the shell. Much ingenuity has been shown in evolving elements for shells of specific geometry.

The results of a series of shear buckling tests on shallow, flat-sided, corrugated webs are presented, and a comparison made with a theoretical analysis in which the web is assumed to buckle either as an orthotropic plate or in a local mode. An expression is derived for the efficiency of a corrugated web in shear, and used to compare the four shapes of cross-section tested.

We envisage here that it is desired to evaluate (using a digital computer) the integral of a function f (x, y) with respect to x (say), along a curve γ in the xy-plane; the value of the function and of the co-ordinates of the curve being known only at discrete, and possibly irregularly spaced, points of γ. Such a problem frequently arises, especially where γ is a closed curve: as for instance in aerodynamics when it is desired to estimate the force components and pitching moment inferred from an experimentally determined set of pressures taken over an aerofoil; here the function values are related to the pressure measurements and γ is the aerofoil contour.

The exercise of carrying out jet V/STOL operations in any given combination of weather and site conditions is clearly open to theoretical analysis and relatively simple solution, along the existing lines of conventional autoland. With present knowledge automatic operation of a jet V/STOL aircraft would not be a very great task, providing that things such as cost, reliability, space, weight, ground equipment, in fact the overall economics of the operation were not allowed to intrude into the problem. But this is not reasonable, the advantages of automatic operation must be weighed against the cost.

Now that the British Services are becoming drawn inexorably into the business of helicopter armament, the attitudes of individuals are widely diverse; some are appalled; some are eager; others mutter evasively “Can't we leave this sort of thing to the professionals?” Number me among the enthusiasts.

My aim this afternoon is simply to air the current problems relevant to helicopter armament in support of British Army operations—in the hope that members of this Society will later come up with clever ideas to solve them.