§ Motion made, and Question proposed, That this House do now adjourn.—[Mr. J. E. B. Hill.]
§ 10.12 p.m.
§ Dr. Jeremy Bray (Middlesbrough, West)
I wish to raise on the Adjournment the question of the boom from supersonic civil aircraft. It will help the House if we get clear from the beginning what kind of boom we are talking about. When any aircraft flies faster than sound it makes a bang on all points along its flight path and for 20 miles on either side, creating a continuous disturbance throughout its flight. This bang is a characteristic double bang, one being separated from another by only a few miliseconds. It is, therefore, easily distinguishable from any other type of explosion the public may hear.
1683 The loudness of the bang depends upon the height, speed and weight of the aircraft making the noise. Certainly, at low altitudes and high speeds, the bang can cause very serious damage to both persons and property, and it has done so in many parts of the world. There is no suggestion that supersonic airliners should fly under such conditions as to make such severe bangs as this. At the other extreme, the bang may be so slight that it is lost against the background noise. In these circumstances, one would expect no complaint.
The problem arises, however, of the intermediate levels—in technical terms, in the ½ lb.—2 lb. per sq. ft. increase in normal atmospheric pressure. In these conditions, the bang sounds like a clap of thunder a few miles away, loud enough to distract attention and to wake people—shift workers, children, Members of Parliament and such like—to make people sit up, perhaps to frighten children and, perhaps, even to delight the aerodynamicist who designed the aircraft. It is in this intermediate range that the boom from the Concord airliners will fall. I am satisfied that the designers of the Concord have sought to minimise the effect of the boom at the flying altitude and speed at which the aircraft will operate. It is obviously in their interests. It also minimises the drag on the aircraft.
It is true that the exact effect of the Concord boom is not known, but if it may be a little more of a "whoomf" and less of a "crack" than the boom from a Lightning, it is true that the change of pressure lasts for a rather longer time and so the secondary effects in shaking windows and doors and glass and so on will probably be greater than those experienced with lighter aircraft. So we know broadly the picture of what we can expect.
What we have to do, therefore, is to weigh the slight increase in convenience to air travellers against the deterioration in the environment of the whole community. It is not a question of what the aeronautical world, the aviation industry and the airlines can get away with, though these are the terms, I am afraid, in which aeronautical people sometimes talk. We are not a Fascist country, and we have to strike 1684 a genuine balance of advantage for the community as a whole.
If we look at how the Concord might be operated, on the London-New York flight there is no need for the aircraft to go supersonic until it gets well over the sea and no need for any boom to be heard over land at all. But on flights into Europe, to the Middle East, the Far East, South-East Asia, Australia and Africa, not to mention inside the North American Continent, substantial parts of the routes, the main trunk routes of the world, are over land, and if we want to fly over other people's territory we must expect other people to want to fly over ours at supersonic speeds. We must expect, in particular, flights from Northern Europe to America to pass over Britain.
The only estimate that I have seen of the numbers of flights likely to be involved is that 20 Concords may well be operating on these routes, making an average of three flights a day—which means 60 booms a day over Britain. If these are spread over three bands across the country, we might expect 15 million people to hear a bang about every half hour.
It is argued sometimes that people must just get used to the bangs as we have got used to traffic noise. But there is a big difference in that every member of the community both benefits and suffers more or less continuously from traffic and the nuisance and the benefits that it conveys. But for aircraft only a tiny proportion of the population flies, and that for only a tiny proportion of the time. Even in America today there are only 33 passenger flights a year for every 100 of the population, and these are probably made by less than 5 per cent. of the population. Therefore, the flying community is very small, and it is likely to remain so for many years.
But it is said that flying is on the increase. Very well. What will be the situation if every person in Britain makes one Concord flight a year over land? If the bang is heard by an average of 5 million people, everyone will have to listen to 50,000 bangs a year, or a bang every four minutes during the day, which will amount virtually to a continuous thunderstorm. 1685 It hardly seems worth it for the convenience of knocking a couple of hours off the flight to Istanbul once a year. So supersonic overland flying, whether for the whole population, which is out of the question, or for a privileged minority, exhibits really the most atrocious manners.
Fortunately for the Concord, the range and the fuel consumption per mile are more or less the same whether the aircraft is flying at subsonic or supersonic speeds. Therefore, mixed sea and land stages are possible. On a flight to Sydney, for example, if a speed restriction is applied over land to subsonic speeds, the flight will take 21½ hours, compared with a wholly supersonic flight of 16 hours. The increase in cost which would occur because the aircraft was occupied for a longer time would be about 20 per cent., which is hardly an insuperable economic obstacle.
Certainly if there were a restriction to supersonic flight only over the sea there would be an economic penalty in the number of aircraft ordered, but it has been estimated that the market would still provide a demand for 130 Concords, which is substantially more than is now hoped will be needed to reach a breakeven point in the numbers manufactured.
While nothing can be done about the kind of boom we can expect from the Concord, it is not true that supersonic flight always causes a bang. For example, the satellites do not cause an audible bang on earth, nor at any stage in their flight. The exact height and, consequently, the speed at which a bang would not be heard upon the surface of the earth is not known, but no doubt it will be found in due course, although not during the lifetime of the Concord. Indeed, there are aero-dynamic shapes which can pass through the atmosphere at supersonic speeds, even at a low altitude, without causing a boom at all—swallowing their own boom as they go.
In the House this evening my objective is not to knock the Concord. I support the project wholeheartedly, and I wish it every success and look forward to flying in it. But the Government should be warned, and should warn quite unmistakably the aircraft industry and the airlines, that supersonic flight overland is just not on, and that there will be a 1686 very strong public reaction once the public begin to experience the effect of the boom on their daily lives.
The Oklahoma City tests are only one stage less naïve than some of the tests carried out by the Ministry of Aviation itself, by which it is true it sets no great store. They consist of exploding charges suspended from a balloon over an explosive research establishment, where the local community makes its living out of the bangs. The more bangs the greater the pay packet. Whatever tests are made are bound to be synthetic, and we have to use our ordinary human and political nous as to the total balance of advantage to the whole community.
I want to make two specific suggestions. First, since the Ministry of Aviation is an interested party—bearing in mind the fact that the scientists and engineers involved have given their lives to this project for the past 20 years they are passionately involved and rightly so—the problem of the supersonic boom should be handed to a Ministry which is used to weighing delicate questions of social and public amenity. I suggest that the Ministry of Housing and Local Government is well equipped to do this. I do not think that it would want such a hot potato, or that the Ministry of Aviation would be very keen to hand it over, but I am sure that in the interests of good Government this would provide a fairer and, in the long term, more helpful assessment of the problem for all concerned.
Secondly, I suggest that it should be specifically stated that supersonic flight overland for the Concord is not on, and that any further planning of the project which is now under way, relating to modifications, flight testing and production, should be made on the assumption that supersonic flight overland will not be acceptable in this country or elsewhere.
This is a question for Britain. It will face us before it faces the United States. As for France, I cannot help feeling that de Gaulle would feel that the bigger the bang the better. What more glorious symbol of the power of France than a French boom—albeit an Anglo-French boom—circumnavigating the globe, going into every hut, skyscraper and home. But this is not the way that Britain behaves. This is a difficult question for 1687 any Government, but it is literally too explosive merely to slide over. If this Government or their successors do not grasp this nettle, with all the international and technical complications involved, I suggest that it will be for this House, in its duty to protect the interests of the community and the established rights of the whole population, to pass a Private Member's Bill, prohibiting civil airliners from making supersonic bangs over Britain.
§ 10.25 p.m.
§ Mr. Rupert Speir (Hexham)
I do not seek to intervene for long in this necessarily brief debate. It is obvious that this subject will have to be discussed more fully in the House in the near future.
I should like to thank the hon. Member for Middlesbrough, West (Dr. Bray) for raising this very important subject. He has directed attention to a horrifying new threat to life in this modern world. It is a menace which will very soon face us all in Britain. Today, it faces particularly people living in rural Britain.
After what has been happening lately, I am not now surprised that when I piloted the noise abatement Act through the House, a year or two ago, the Ministry of Aviation was determined and emphatic that aircraft and aerodromes should be excluded from its provisions. As America has already discovered, and we in Britain are now to discover, the supersonic bang problem is very much more serious and worse than we ever feared that it would be.
In recent weeks, in rural areas in the north of England, we have suffered from the sound barrier having been broken on at least a dozen occasions. The dreadful and worrying thing, I think, is that no one knows just how much damage the resulting shock waves have done to life, both human and animal, or to property—to foundations, walls, roof tiles and panes of glass. I do not suppose that we ever shall know exactly how much damage these shock waves do cause. We know that the damage has been quite considerable already. Some of it is obvious and some is hidden. Some of the damage is open for anyone to see, but a great deal will remain secret for many years to come.
We also know that although the Americans now consider that a shock 1688 wave of even 1½ lb. per sq. ft. is excessive, the Ministry of Aviation is calmly authorising fights to take place at supersonic speed overland in Britain which give rise to shock waves 25 per cent. above the level which the Americans now consider the maximum which should be allowed. I consider that this position is pretty well intolerable. It is unacceptable and monstrous that the Ministry of Aviation should decide that during the next 12 weeks no fewer than 75 supersonic flights should take place overland in Britain without a full knowledge of all the consequences and side effects that these supersonic flights may well cause.
I understand—I should like the Parliamentary Secretary to comment on this if he can—that some of these flights will take place at heights below 35,000 ft. I say emphatically that supersonic flights generally ought to take place only over the sea. If, for a special experimental reason, they must take place overland, arrangements should be made for them to take place somewhere abroad, over sparsely populated country. I consider that the Ministry of Aviation is treating this problem far too casually. If the Minister will not accept some limitations he will find that the whole of rural Britain is up in arms, and on this occasion I think that rural Britain will win the fight, and will deserve to win it.
§ 10.29 p.m.
§ Mr. John Cronin (Loughborough)
I should like to congratulate my hon. Friend the Member for Middlesbrough, West (Dr. Bray) on having raised this subject and on the lucid way that he explained the problem. The Opposition have always supported the Concord project. We always support any opportunity to deploy the technical resources of Britain, and to help our prosperity and give increased employment to the aircraft industry. But we have given our support always with reservations. One principle reservation has been in respect of the amount of noise which is likely to be generated by supersonic aircraft.
There is no evidence so far that this noise problem has been overcome or is likely to be overcome in the immediate future. It would seem that there is danger that hundreds of thousands may be grossly inconvenienced in giving increased speed of travel to a few dozen people each time there is a supersonic 1689 bang. We regard such a situation as quite intolerable. Mr. Halaby, who in the United States is the equivalent to our Minister of Aviation, said a few weeks ago:We do not think the President should be asked to sanction our proceeding with the supersonic transport without some knowledge of this problem.He was referring to the supersonic boom. These are very grave words on the matter of supersonic transport.
I hope that the Parliamentary Secretary will give us a comprehensive reply to the points put by my hon. Friend the Member for Middlesbrough, West. I hope he will tell us what is to be done about the Concord. Is it to be confined to operating only over the Atlantic? If so, will it be economically viable? Perhaps he will also take the opportunity to tell us the revised estimate of the supersonic aircraft. There has been evidence to suggest that the cost will be more than the £180 million originally budgeted for.
I hope that the hon. Gentleman will tell us to what extent this enormous investment is likely to be jeopardised by the problem of the supersonic boom.
§ 10.32 p.m.
§ Mr. Timothy Kitson (Richmond, Yorks)
I endorse the remarks of my hon. Friend the Member for Hexham (Mr. Speir). I, like him, have a very sparsely populated constituency. In fact, mine is the most sparsely populated in England, and the Ministry of Aviation makes far too many tests over it. I should like the Parliamentary Secretary to say how those who suffer damage are to be compensated.
In a dales area, such as Wensleydale, Swallowdale and Teesdale, where roofs are of stone, damage is considerable. Damage is not so much due to Concord tests as Lightning tests. It is absolutely essential that these tests should be made over sea or over land abroad much more sparsely populated than my constituency. If there are 75 supersonic tests during the next 12 weeks the number of letters we shall receive from constituents will be prohibitive. I hope that my hon. Friend the Parliamentary Secretary will explain how compensation can be granted to individuals.
§ 10.33 p.m.
§ The Parliamentary Secretary to the Ministry of Aviation (Mr. Neil Marten)
In the few minutes left to me, I am afraid that I cannot give a comprehensive reply to the hon. Member for Loughborough (Mr. Cronin). Perhaps, on a future occasion, we can have a further debate on this extremely important subject.
I am glad that the hon. Member for Middlesbrough, West (Dr. Bray) has raised this subject. We can regard this debate as a cocktail to quite an orgy. He has drawn attention to what undoubtedy will be a very important factor in the operation of civil supersonic transport aircraft, and one which I can assure the House the Government are taking most seriously. We have already done a vast amount of work on the subject of the boom, and we shall continue our researches and experiments with the utmost vigour.
As the hon. Member said, when aircraft fly at supersonic speeds they create a sound wave, just as a ship moving through the water creates a bow wave. From an aircraft there are two waves, one from the nose and one from the tail. Sometimes the double wave merges and we get a single boom. The loudness of the noise depends on a variety of factors—proximity of the actual flight path, the height of the aircraft and its size, atmospheric conditions, ground topography and so on. Our latest findings tend to indicate that the rate at which the pressure rises—and so affects the eardrums—may be more important than the actual degree of over-pressure measured. The noise heard on the ground may also vary with different aircraft. As the hon. Member said, it is sometimes a "woof" and sometimes a bang.
I have listened to a series of bangs I went to Aberporth, in Cardiganshire, and had a whole series of these bangs made over me. The over-pressure which was measured on that occasion was between 1½ and 2½ lbs. per sq. ft. I listened to these bangs both out of doors and indoors, and I must say that I did not find them particularly worrying or alarming. But that is me—and it is a subjective matter. At about 2 lbs. per sq. ft. my reaction was that it was rather 1691 like an explosion which one would hear from a stone quarry about a mile away.
I think that it is important that we should not, by this debate, generate any alarmist thoughts about the problem. In my view, it is something which people will learn to live with—and I do not agree with the hon. Member here—just as they have learned to live over the last 100 years with railways, motor cars and jet aircraft.
§ Mr. Marten
This is all part of the research which is going on and which will go on before the Concord comes into service. We shall be studying that in great detail.
I want to tell the House what is being done on this matter, because it does not seem to be known by the public at large. The Royal Aircraft Establishments at Farnborough and Bedford have been working on it for some time. Considerable theoretical work has been done in predicting the waveforms and the overpressures which can be expected from supersonic flight. This has been substantiated by wind-tunnel measurements and by measurements on the ground from Lightning aircraft—sometimes over Hexham, I am afraid—in flight.
The hon. Member said that only the Ministry of Aviation is responsible. In fact, the Applied Psychology Research Unit of the Medical Research Council has been studying this question at Cambridge. It has been studying the relative annoyance of sonic booms and ordinary aircraft noise and it is engaged in studying the effect of sonic booms on working efficiency. In addition, the University of Southampton has been investigating the importance of waveform characteristics. The National Physical Laboratory has been examining noise levels indoors, and it is following up the work done by Southampton University with more elaborate experiments. The work is not restricted to the Ministry of Aviation, which I agree has, or ought to have, a vested interest in the matter.
The Royal Aircraft Establishment has carried out an exercise over a three- 1692 month period to find out the subjective reaction of a community to explosive noise similar to that of the sonic boom, and it has concluded that people do get used to it to some extent. Measurements are being made to determine variations in sonic boom over-pressures caused by meteorological conditions. This is one of the varying factors. At the same time, the Americans are carrying out their tests over Oklahoma, and they hope to conclude these tests in August. When he was in America earlier this year my right hon. Friend visited Oklahoma, where these tests are being carried out. He told me that the main controversy, about which we have read in the newspapers, was not so much about the bangs themselves as about the political issue of whether and where the tests should be carried out.
Certainly, Oklahoma is a very important experiment which the Americans are carrying out, and we and our French partners in the Concord project are in close touch with the Americans about it. We have already received certain preliminary information, and I have a booklet here which I will let the hon. Member read if he is interested. We shall be receiving the remainder of the information on the work which they are doing, but until the tests have been completed and thoroughly analysed it is premature to start trying to draw deductions from them. My hon. Friend the Member for Hexham claimed that the Americans had said that 1½ lb. per sq. ft. pressure was unacceptable. I do not think that they have yet come to such a conclusion. Many of us have seen various newspaper articles commenting on the tests, and this may be what my hon. Friend had in mind. These inevitably give only very partial reports, and I suggest that it is important not to be swayed one way or another by them.
The important thing is to await the full analysis of the tests and to relate them to our own knowledge of the subject. Only when that has been done shall we be in a position to decide whether we should carry out a large-scale experiment of this sort in this country. At that stage we shall bring in other Government Departments, as the hon. Member suggested, and we shall have to consider how we should handle the social survey, which we should have 1693 to make and which would be a necessary part of the experiment. I am grateful to the hon. Member for having raised the point, which I note, and which will be given further consideration when the time arises. I can assure the House that we would consult fully with the local authorities in any areas which might be involved.
§ Mr. Marten
I will write to my hon. Friend. [An HON. MEMBER: "Get it on record."] If the hon. Member will put down a Question I will answer it and, that way, it will be on the record. There are well laid down procedures and compensation is paid.
From the point of view of this country, aircraft operating out of our airports will almost always be over the sea before they go supersonic and we shall mainly be concerned with supersonic overflights. 1694 With respect to the hon. Member for Middlesbrough, West, I think that the figures which he gave were rather exaggerated. We have power to control the routes and heights of aircraft overflying this country.
I hope that I have said enough to show that both we and the French are taking this aspect of the Concord's development very seriously. We are both doing a great deal of research on the problem, and this will continue. We certainly have no intention whatever that the Concord should be operated in such a manner as to become a positive nuisance to those areas over which it passes. On the contrary, it is our firm intention to develop this aircraft so that it will fit satisfactorily into the pattern of living of the 1970s and 1980s.
§ Question put and agreed to.
§ Adjourned accordingly at nineteen minutes to Eleven o'clock.