The first point which must be made—and I may not be the only speaker today who will make it—is that there is nothing new in a low air fares policy, at least so far as the United Kingdom is concerned. During the 1950s British independent airlines pioneered low fare scheduled services to Africa—the ‘colonial coach’ services. Much of the expansion in air travel that occurred between the United Kingdom and Europe and on the North Atlantic in the 1960s was due to the availability of low fares on charter services. Control over the minimum prices of inclusive tour holidays in Europe was finally suspended by the United Kingdom in 1972. In the same year, Edward Heath, addressing the Annual General Meeting of IATA in London, bluntly warned the scheduled airlines of the world that if they did not cater for the mass travel market by offering low fares, Governments would make sure that somebody else did. In the same year Laker Airways was licensed to operate a Skytrain service to New York—a scheduled service geared specifically to a low fares policy.

This last year has shown how delicate a balance exists between all constituent parts of our travel industry. Airlines, airports, air navigation, governments, travel trade, hoteliers, tourism institutions, aircraft manufacturers and above all, consumers have faced uncertainty and change. Most changes have been sudden, some have been successful, and others have proved difficult.

Main beneficiaries of recent relaxations in price and entry rules have, so far, been some scheduled airlines (through increased revenue) and some passengers (through lower fares). Airports, charter airlines, people living near airports, tourism institutions, even governments, have all shown less enthusiasm (especially at peak times).

It is said that 1978 was a great year for the consumer: IATA's face was pushed in the mud; President Carter had a great new freedom of the skies policy; and the CAB had a new deregulation policy. At long last the consumer benefited from the massive new spread of low fares.

This is a gross exaggeration; low fares have been around for a long, long time. European inclusive tours, for instance, through the fifties, sixties and seventies, through trials and disasters, have grown to be a new way of life for the holidaymaker and vacationer from Northern Europe, who vacates Northern Europe en masse in the spring, in the summer, through the autumn and goes to the Mediterranean. No other way could that have been done without the promotion of low fares as part of a total package.

The views I am putting forward today are my own I and may not represent the views of other independent airlines.

Low fares are not a new feature of the Civil Aviation industry. After all, charter airlines have been providing low cost air transportation for the past three decades, and what a painful process the development of those services has been. For years scheduled airlines, backed by Government regulatory agencies, subscribed to the theory that charter services, if liberalised, could lead to the destruction of scheduled services and therefore scheduled services should be protected. In the UK, the growth of Inclusive Tour Charters to points in Europe was slowed down by capacity restrictions and by pricing policies designed to minimise diversion of traffic from scheduled services.

Passenger traffic through the seven BAA airports, Heathrow, Gatwick and Stansted in the South-East and Glasgow, Edinburgh, Prestwick and Aberdeen in Scotland is predominantly in the leisure sector and this sector is most affected by low fares. In 1978 this sector formed 65% of all traffic at the three South-East airports and 55% at the four airports in Scotland.

As Ray Colegate and Adam Thomson have said low fares are no new choice for air travellers. Low fares for charter operations with a range of fare options have been the main feature of the rapid passenger growth at Gatwick Airport for many years. This is also the case at Luton Airport which is not owned by the BAA but serves the South-East.

Both within the US, and on the North Atlantic, there has been a dramatic reduction in governmental control over airline pricing routeing and service policies. In the short run, the most visible and important development has been the substantial decrease in average fares, spearheaded by greatly reduced fares available in certain restricted circumstances.

Because decisions about price, routeing and service interact, I find it most useful to talk about the loosening of governmental strictures on them, collectively, as deregulation, and I want to concentrate my remarks on the impact of deregulation from my perspective as an observer of the industry, and as an airport operator. I hope also to develop the theme that loosening one of these strictures without attention to the others can adversely affect air service.

To begin I should like to point out that Aeroport de Paris is a public establishment, somewhat similar in structure to the British Airports Authority, whose role is to conceive, study, build and operate civil airports in the Paris region. Our two major commercial airports are Orly and Roissy-Charles de Gaulle. In 1978 their cumulated traffic amounted to 23·5 million passengers, 500 000 metric tons of freight and 290 000 aircraft movements.

The recent history of world air transport is marked with profound upheavals: the advent of jet aircraft, then of jumbo jets, the growth of charter airlines, the creation of airlines by countries having obtained their independence, oil crises, … the latest of these events laden with consequences is without doubt the fundamental questioning of the tariff system as demonstrated by IATA's breakdown, the American deregulation and the re-negotiation of bilateral agreements.

The growth potential of air transport has been realised since the late 1960s /early 1970s when, in the UK, imaginative marketing by tour operators caused a boom in bookings for inclusive tour holidays and scheduled airlines operating across the Atlantic in this period introduced the first of an eventual flood of discount fares. However, far from the expected revenue boom, the eventual reductions in average yield caused by the inflow of ‘new’ passengers and the unexpected cross-over of full fare paying passengers started these airlines on the road to an eventual $2.5 billion loss over a seven year period. An unfortunately timed fuel crisis also added to the difficulties.

Now is the time of reckoning: airlines seem to be moving to a three class service (on the North Atlantic at least), similar to that operated in old steamship lines, in an attempt to maintain revenues from full fare passengers and at the same time encourage ‘discount’ travel.

The proliferation of discount fares and their understanding by the regulators, or for that matter, by the travelling public, is one of the most complex, if not bewildering aspects of today's airline industry. You may consider it presumptuous for me, representing an aeroplane manufacturer, to comment on airline fares policies. However, as part of an industry directly affected by whether or not airlines are profitable, we are very ‘interested parties'. This interest has invoved us in many discussions with airlines, as well as in Boeing-sponsored studies to understand discounted fares and the basis for their being profitable or unprofitable. Low fares, of course, are only one aspect of a rapidly evolving air transport industry—one which is seeing a new regulatory environment in the United States, new forms of bilateral agreements, and a whole host of fresh marketing ideas.

'Low-Fares’ is a misleading term. Low compared with what? It certainly implies change. Perhaps ‘lower’ fares are what the debate is all about. There are tourism as well as aviation conditions.

Fares are vital to tourism. A quarter of a century of low fares has supported the world tourism boom, making tourism the biggest single factor in world trade, and produced a growth rate of 8-9%, considerably higher than that for world trade as a whole. In particular, the trans-Atlantic fare revolution is not new.

The journal of the ITA gave an illustration of this, comparing a package tour New York/Rome for Holy Year 1950 priced at $585 and the same offer for the second Holy Year 1975 at $580. Taking into account the equivalent dollar purchasing power, the 1950 offer represented a price of $1400. ‘Eternal bliss', said the ITA reporter, ‘at half the price!’

Tourism is both a growing industry and is also an increasingly competitive one. It has become an important factor in the social and economic life of this country, but it is the international visitors who form the growth sector in the market and make the greatest contribution to the national economy. In 1977 the United Kingdom attracted 4·7% of the world total of international travellers and its share of the growing world market has increased by half over the past 10 years. Figures from the Department of Trade show that in 1977 tourism was third in the league of invisible exports and seventh overall in export earnings.

If the advent of cheap air fares is to lead to a tourist ‘explosion’ then the effects are likely to be dramatic in terms not only of the tourist industry but the social life of places visited as well as on the national economy. As the foremost tourist centre in Britain, London will feel the effects soonest and most dramatically. While this provides very welcome opportunities, the social and economic implications are far-reaching and need to be carefully considered.

The first point which I wish to make, speaking on behalf of the Air Transport Users Committee, is that low fares are still an exception rather than the rule outside North America. There are some genuine low fares on the North Atlantic and many inclusive tour fares from this country, as other speakers have said, can be classified as genuinely low. Elsewhere in the world fares are still much too high, although we have been glad to see a slight reduction in fares to Scandinavia and to Australia.

While users very naturally are interested in low fares and do not wish to pay more than is absolutely necessary for their travel, they do have reservations regarding low fares which are achieved by very high seat factors rather than by genuine reduction in cost.

Free flight testing of missile designs is generally necessary to confirm that accurate estimates have been made of effects due to the change in size from wind tunnel model to full scale missile and of effects arising from the flight dynamic behaviour of the missile. The amount of such testing is generally limited by the high costs involved and so every effort is made to obtain the maximum information from each flight trial. During recent years parameter estimation techniques have been developed to provide superior methods for analysis of free flight tests. They enable the analyst to extract the required data with greater accuracy from fewer tests than has previously been possible. The old equation error methods relied on measuring all the variables characterising the projectile motion and using the equations of motion to obtain a relationship between aerodynamic forces and moments and translational and angular velocities of the vehicle.

In the analysis of aircraft flight dynamics problems at high incidence, non-linear aerodynamic effects are of considerable importance. The aerodynamic phenomena are generally extremely complicated and the non-linearities may be difficult to predict quantitatively. In this note we confine our attention to longitudinal symmetric motion at constant speed and height. Our aim is (i) to enable the pilot to know when he is in a potentially dangerous manoeuvre (which could lead, for example, to a super-stall) and (ii) to determine simple control laws for an autopilot which would prevent such a super-stall occurring.

Interference fits are an effective method for improving the fatigue performance of bolted joints. The use of Taperlok bolts in aircraft joints is one such example. One of the most important but difficult problems to analyse in these joints is their behaviour after the onset of separation between pin and plate.

Extensive work has been done in the past for the analysis of interference fit joints prior to separation. A comprehensive survey of this area (up to 1965) was brought out by Venkataraman. He also presented many new analytical solutions by a direct method of continuum analysis for interference joints in finite domains. Analysis of these problems in the pre-separation zone continues to draw attention and recently, John Crews used a complex variable technique to analyse the stresses around a flexible pin in an infinite plate under uniaxial tension.