The June 1963 Report of the Inter-Departmental Committee on the Third London Airport concluded that a third London Airport would be required in the early 1970's, and possibly a fourth soon after 1980. It also brought out that because of the large amounts of air space required for the sequencing areas and approach paths of each airport, and because of limitations imposed by the positioning of the main air traffic routeings, the choice of possible sites within reasonable distance of Central London for the third airport was severely restricted. In a postscript to the Report, it was recognised that after the third airport has taken over a further block of air space, the difficulty of siting a fourth airport would be even more severe.

The Airline is satisfying a demand, a demand for transportation. Such transportation is not something in itself—people do not simply go for the ride—but is part of a bigger demand. The airline attempts to create, stimulate and, to some extent, change this demand by tariff and other means but nevertheless it is attempting to satisfy a naked demand as it arises. If the demand is for 8 a.m. out of Glasgow, we as an airline—contrary to popular opinion— attempt to satisfy the demand at that time within the overall context of profitability. In a competitive situation—and this includes competition with other forms of transport, not simply air, as well as other forms of consumer expenditure—the airline's ability to take of this demand what suits it and ignore the rest, is strictly limited. The success of an airline depends upon the efficiency with which it satisfies this demand.

There are several ways of judging the efficiency with which a terminal area is organised. Commercial operators are interested in the cost of the deviations or delays which they are subject to when using the principal terminal airports. Other users of the air space are concerned with the restrictions which terminal area procedures impose on their movements; while ATC (Air Traffic Control) authorities are interested in the cost of the ground facilities necessary to move the traffic with safety and expedition. In this paper we shall discuss mainly how delays and deviations may be minimised. Nevertheless, the procedures which result from this survey will lead to benefits for all and to a freer use of the terminal air space by other traffic.

The ATC system must ensure the safe and expeditious movement of traffic through the TMA and down to and along the surface of the airport. There must be a plan which defines the path to be followed by each aircraft, taking account of all other proposed movements. There must also be a means of implementing this plan with adequate accuracy, or for revising it should later events make this necessary. The plan must take account of the finite accuracy with which an aircraft can navigate (using “navigation” in the broad sense of “the progress of the craft about its ways in space and time“). We will therefore discuss first the tools required for implementing any chosen plan, before discussing the planning function itself.

I hope that I shall be forgiven if I deal only in part with this subject, and also if I approach it from the airline engineer's point of view, although what I have to say is a personal expression of opinion.

Airlines are commercial undertakings and do not welcome change for change's sake. To improve service competitively from the point of view of time, regularity and safety and to encourage the continued growth of traffic through reductions in fares is the broad aim; it is against this background that, for example, the supersonic transport is being considered by the airlines. As you may have gathered, there is no marked enthusiasm. In due course, come it will, and traffic management plans must bear it in mind in considering future developments in Air Traffic Management. I am going to adopt the rather conservative attitude that most air traffic over the next two decades will be in aircraft much as we know them at present, and that if the growth in traffic leads to difficulties in Air Traffic Management then the main source of improvement must be sought in the system of management.

In comparison with the previous papers, this one is somewhat speculative in tone. In discussing commercial VTOL there is little hard fact to form a sound basis for extrapolation as there is with conventional aviation.

But we do know that relatively fast VTOL aircraft can now be engineered around the jet, the fan and the propeller. It also seems that VTOL may offer some peculiar advantages and bring about a significant increase in the capacity of the air transport system as a whole.

So it should be useful now to discuss in pretty broad terms the impact of the higher performance type of VTOL on the system: it will certainly be invaluable to the aircraft constructor to try to find out the influence of the whole air transport environment upon the design of the vehicle itself.

An analysis is presented for equilibrium of yawing moments for a yacht sailing in the displacement mode in smooth water. The geometry of hull form and sail plan are quite unrestricted, although special attention is given throughout to currently popular types.

The free-surface flow is simplified by a reflection technique. In cases where the hull form is appropriate, the hull hydrodynamics are treated by lifting-line theory: in other cases slender-body theory is applied. The sail aerodynamics are treated by methods taken from aerofoil theory. Some design charts are given and computation methods are suggested for practical design calculations.

Static directional stability is treated theoretically and some general conclusions drawn regarding the influence of various characteristics on stability.

Where the theory has been applied, results have agreed with the available experimental data within the limits normally provided for adjusting balance of helm. Changes of balance with angle of heel and static stability have been given by the theory at least qualitatively correctly; experimental results are, however, not available for comparison.

A large lump of ice fell from a cloudless sky one morning in September 1964 and landed only ten yards from a farmer in the Brits district of the Transvaal, South Africa. A whirring sound shortly before the impact alerted the farmer so that he saw the ice as it struck the ground.

The lump was flattish-shaped and irregular, estimated at 11 x 9 x 6 inches, and gave off a peculiar odour. The farmer also observed that the ice was composed of numerous layers and that parts of its interior were brownish-coloured. He did not recall noticing aircraft in the vicinity at the time of the incident.

An analysis of experimental results shows that the maximum pressure rise attainable in a two-dimensional subsonic diffuser of length L correlates with the parameter L/δ0*, δ0* being the displacement thickness of the boundary layer at entry. The results agree well with boundary layer theory.

This Note is concerned with the axisymmetric buckling of orthotropic circular plates. A circular plate fabricated with radial and/or circumferential reinforcements may be idealised as an orthotropic plate of uniform thickness h having different material properties in the radial and circumferential directions.

“The Rank Technique” is a method for automatic selection of redundancies in the Matrix Force Method. The method was developed for the complete linear analysis of general plane frames, but is equally applicable to other forms of two- and three-dimensional configurations whose state can be expressed as a system of linear equations. An attractive feature of the method is that the structure is systematically and automatically investigated to determine its basic characteristics. The first point considered is whether the structure is stable or unstable for the prescribed load conditions; if stable, whether determinate or redundant and if redundant, the degree of redundancy. A consistent set of redundants is automatically isolated. For general structures the technique automatically generates the basic and redundant load systems in an indirect manner which can be made readily available, if required. The initial development of “The Rank Technique” was carried out in collaboration with Robert R. Regl and is given in reference 1.