HC Deb 19 July 1968 vol 768 cc1914-20
Mr. William Rodgers

I beg to move Amendment 29, in page 17, line 14, leave out 'exceeding the speed of sound' and insert: 'in excess of Flight Mach 1'.

Mr. Speaker

We shall debate at the same time Amendment 28, in page 17, line 13, leave out from 'aircraft' to end of line 15 and insert: 'in the airspace of the United Kingdom at speeds in excess of Flight Mach .98 '.

Mr. Rodgers

This Amendment deals with a matter which was much discussed in Committee. I found the debate most interesting in a field of which I had previously very limited experience. In the hope of meeting the wishes of the House, I have proposed Amendment 29. In Committee, the hon. Member for Tiverton (Mr. Maxwell-Hyslop) made three points: first, that the reference to the speed of sound was not sufficiently definite as it did not make clear that the reference was to the speed of sound in the ambient conditions; second, that speed should be defined in terms of Mach numbers; third, that power should be taken to regulate speeds just below supersonic speeds.

On the first point, the present drafting was adopted because it was considered to be sufficient for providing the vires, though it was always realised that it would be necessary to go into more precise detail in drafting Orders in Council. However—here I respond to the hon. Member for Gloucestershire, South (Mr. Corfield)—there is no harm in being more precise, and for this reason I am happy to commend the Amendment to the House.

I have considered the other points made by the hon. Member for Tiverton and have much sympathy with what I take to be the spirit of the Amendment standing in his name and those of his hon. Friends, to insert a reference to air space. However, having looked at it, and in the absence of further explanation at this stage, as there is no legal definition of air space, I feel that we meet the substance of his Amendment by our Amendment, whereas I should have to resist his.

3.15 p.m.

Mr. Maxwell-Hyslop

The Amendment covers some of the ground which I desire to see covered, but it does not cover nearly enough. The Minister has been quite persistent on one point without giving any explanation.

This is an enabling Clause which enables the Minister to make regulations, not a mandatory Clause. By having as the lower limit Mach 1 he is tying his hands so that he cannot make regulations which will prevent aircraft inadvertently going through Mach 1. Hon. Members who have had the experience of complaining to Service Ministers about military aircraft exceeding Mach 1 and producing sonic boom, will know that more often than not the reply to that the pilot has done so accidentally in the course of avoiding action or a manoeuvre of some kind. He has accidentally gone through Mach 1 although he was intending to fly below it. That is why I pressed strongly in Committee that enabling powers should be taken at a lower limit, just below the speed of sound. I hope that the hon. Gentleman the Member for Putney (Mr. Hugh Jenkins) will take this point.

If the only enabling powers that the Minister takes have a lower limit of Flight Mach 1, in many cases that will be inadequate to deal with the situation we want to prevent, which is aircraft exceeding the speed of sound and producing serious sonic boom conditions over inhabited land masses. If the Minister would accept an Amendment to make it Mach 098 he would then have power to lay effective regulations, which he will not have if he sticks to Mach 1 for no good reasons. He does not gain anything by sticking to Mach 1. He is being obstinate, and there is no technical reason for sticking to Mach 1.

The words used in the Bill are "over the United Kingdom". Clause 18(1) refers to: … regulating or prohibiting the flight of aircraft over the United Kingdom at speeds exceeding the speed of sound". These are the words which the Minister proposes to amend, while still leaving the words "over the United Kingdom". This means, as I read it, that aircraft can fly supersonically a quarter of a mile off the coast, which is not "over the United Kingdom", and the Minister will be powerless by this Clause to make regulations controlling that.

For Heaven's sake, if we are to have an enabling Act, we certainly need to control matters of this kind, let us make the enabling Act as wide as possible so that the Minister in making regulations can draw them as widely as is necessary to meet aspects of a problem which even he with his vast technical knowledge may not anticipate at this moment.

Mr. Holland

Would my hon. Friend probe a little further and inquire whether "the United Kingdom" includes territorial waters which would cover a 12-mile limit?

Mr. Maxwell-Hyslop

Yes indeed, but the shape of the debate during the last three-quarters of an hour has been that the Minister does not attempt to answer points which have been brought up in debate.

Mr. Rodgers

Yes.

Mr. Maxwell-Hyslop

The Minister says yes. That is a good start. Perhaps on the remaining Amendments we will have a proper answer instead of being told that there is an unspecified drafting defect and leaving it at that. I certainly am not prepared to leave it at that.

The matter was raised in Committee, and the Minister has had plenty of time to deal with it and to specify why he is tying his hands quite needlessly. As the Minister quite possibly is not aware, the speed of sound depends upon a number of conditions which are not under the control of the pilot of the aircraft. Ambient temperature is one of them. Although the pilot can very often but not invariably control the altitude at which the aircraft is flying, he cannot control the ambient temperature. As the Minister will now know if he has read the Official Report of the Committee Stage, the speed of sound under international standard atmosphere conditions, but only under those conditions, is 760 knots at sea level and 660 knots at the beginning of the tropopause. In other words, it is a varying speed. It is not the case that a pilot can accurately predict what temperature strata he will run into in the course of flying along a given flight path. It is because of that that a pilot can quite unintentionally exceed Mach 1 when he does not mean to and is not allowed to. The only way effectively of preventing it from happening is to start regulating the conditions under which pilots are flying at a speed below that which they must not attain. I would have thought that that followed as night follows day.

That is why anyone who is interested in preventing civil aircraft flying super-sonically over inhabited land masses has a vested interest in seeing that the Minister gives himself adequate powers in the Bill, because there will not be another for a long time and, at the end of Report on this Amendment, this is the last occasion when he will have the opportunity to do so. When supersonic aircraft are in service, it will be too late for him to wish that he could take powers under the Act which he has deliberately denied himself, when the technical case has been explained at length in Committee and his predecessor showed a very receptive attitude towards it.

There is nothing in the Amendment which forces the Minister to make recommendations which he does not want to make. It is purely enabling. If the Minister wished in another place to add a definition of "United Kingdom air space", may I remind him that it is generally accepted internationally that a county's air space is a theoretical column extending not only over its land frontiers but also over its territorial waters. This has been established for many years. If the hon. Gentleman cares to consult his right hon. and hon. Friends in the Foreign Office, he will learn that complaints about the infringement of air space very often come when no land has been crossed but when foreign aircraft intrude into that portion of the air space which is inside the exterior limits of its territorial waters.

By adopting the form of words that he has, he has restricted his power to aircraft which are flying physically over the United Kingdom. If, for example, they are flying up the Bristol Channel—

Mr. William Rodgers

The hon. Gentleman has not got a point here. I answered yes to the intervention by the hon. Member for Carlton (Mr. Holland). I was seeking simply to help him. He made a fair point. I have considered it fully. But I have given a straightforward answer that the provisions of the 1949 Act deal wholly with the point that the hon. Member for Tiverton (Mr. Maxwell-Hyslop) is seeking to make in his Amendment.

Mr. Maxwell-Hyslop

Unfortunately, the drafting which the Minister has adopted is not very helpful in that respect. But where he says "over the United Kingdom", he has not made it clear that those words include the United Kingdom air space outside the column of air space going vertically above the land masses.

Mr. William Rodgers

It does.

Mr. Maxwell-Hyslop

It may be that there is a general definition in the 1949 Act which includes United Kingdom territorial waters external to the United Kingdom. That is possible, but it was not an explanation offered by his hon. Friend in Committee. If by any chance the 1949 Act covers that point, well and good, but certainly it does not cover the point about Mach .98.

I think that we can predict with reasonable accuracy, as it is logical to assume that the Minister is getting advice from the same quarter as his predecessor did, that when the debate on this subject is concluded—and I trust that he will not intervene before it is—he will say that he is advised—and, not being technically informed himself, he will not know whether it is good advice—that sonic boom is not produced until an aircraft is flying considerably in excess of an indicated Mach I, which is what his hon. Friend said previously. It will be just as irrelevant and significantly untrue as when his hon. Friend said it.

Unfortunately, although it may be a defence to the Minister constitutionally to take bad advice, it does not make good law. His predecessor was good enough to invite me to discuss this with those who were advising him technically, although the present Minister thought that that was unnecessary. I can only assume therefore, that he has looked further afield for advice than did his predecessor, and, as a result, he has been able to have an independent check on the advice which was previously available to his predecessor. I should like to believe that was true, but I very much doubt that it is.

So we come back to the situation in which, as drafted, what is now Clause 18 does not succeed in doing what every hon. Member seeks to do. The Minister has added a titbit. He has defined the speed of sound in a Mach number, the necessity for this having been explained at considerable length in Committee, but he has still stuck to Mach I and will not come down to Mach .98. I end as I began by saying that if he accepts the starting point of Mach .98, that will not force him to use that in his regulations. He will lose absolutely nothing. He does not believe me, but I am telling him that if he limits himself to a starting point of Mach I, he or his successors will regret not having the power which they will need, and many people who already suffer severe discomfort from aircraft noise will look back longingly to the days when it was only aircraft noise which distressed them and before they started getting pressure waves of the magnitude of up to 2 lbs. per square inch, as is possible, although the Minister has not experienced it, with supersonic flight by heavy aircraft, particularly when they are undertaking some fairly violent manoeuvre. I beg him to take the opportunity of listening to the points of view of other hon. Members and at the very least to say that there is a considerable doubt and that he will legislate for the benefit of that doubt at Mach 98 rather than Mach I.

Mr. Hugh Jenkins

We are all anxious that the Government should get the Bill, including its Third Reading, this afternoon and, as is my normal custom, I shall intervene for only two minutes. I have intervened only once before today and that for only two minutes, and I shall do the same again. It is necessary for me to intervene because of what the hon. Member for Tiverton (Mr. Maxwell-Hyslop) has been saying. The hon. Member was arguing that we have the bread and even that we recognise that there is a little jam, but that we do not like the colour of the jam. I am sorry that the general atmosphere of peace and harmony which prevailed when I was here earlier seems to have broken down and I am anxious to bring my beneficent presence to bear in order to bring us back to where we were.

It is the manner in which the Minister interprets the regulations which he will issue under the Clause which will decide whether the fears of the hon. Member for Tiverton are justified. For my part, I am prepared to give the hon. Member the benefit of the doubt.

3.30 p.m.

What I think the Minister will do will be to issue regulations laying down the circumstances in which such flights may be undertaken, and if the regulations say that only in these circumstances may the speed of sound—to use the common usage—be exceeded, it seems to me that the object of the exercise is achieved. In the strictly technical sense, I think that the hon. Gentleman is right, and I do not see why my hon. Friend cannot accept the Amendment, but I may have given the explanation. It would be difficult to cast regulations saying, "Not only can you not exceed the speed of sound but you cannot nearly exceed the speed of sound". That being so, I think that my hon. Friend is right, and I hope that the hon. Gentleman will not press the Amendment.

I pestered my hon. Friend's predecessor, a pestering which he met with very great courtesy, and finished up by accepting the point of the pestering by himself introducing an Amendment in Committee. That is something on which he is to be congratulated. We now have a Clause which, if the Minister wishes to lay regulations, may be of great benefit to us all. We shall need that benefit because, with the arrival of Concorde—and the Ministry has already paid out £150 in one case for damage to hearing—supersonic flying constitutes a very real threat to the community. It is essential that the Minister should exercise his right under the Bill and that the regulations should be firm, just and adequate to protect people from the consequences of supersonic flying.

Amendment agreed to.

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