HC Deb 01 August 1951 vol 491 cc1441-5
31. Commander Maitland

asked the Parliamentary Secretary to the Admiralty if he will make a public statement about the loss of H.M.S. "Affray" before the House rises.

32. Mr. J. P. L. Thomas

asked the Parliamentary Secretary to the Admiralty what progress has been made by the Naval Board of Inquiry into the loss of H.M.S. "Affray."

33. Surgeon Lieut.-Commander Bennett

asked the Parliamentary Secretary to the Admiralty what further news he has of the inquiries into the loss of His Majesty's Submarine "Affray"; whether he will consider salving the wreck as a useful exercise, if the risks are not excessive; and whether he will release all facts that may come to light, other than those that are needlessly distressing or contraindicated on grounds of security.

The Parliamentary and Financial Secretary to the Admiralty (Mr. James Callaghan)

As the reply is rather long, I will, with permission, answer these Questions at the end of Questions.

At the end of Questions—

Mr. Callaghan

In the 47 days since the wreck of H.M. Submarine "Affray" was found, diving has been possible only on 15 days. Suited divers, who can be used for only one hour in 24 at this depth and in these tides, have made six descents, and 26 dives have been made by observation chamber. Diving was suspended for a short time because the submarine became unstable. She is now lying at an angle of at least 50 degrees and seems to have settled there.

With great determination, the divers have made an examination of the whole length of the submarine, but apart from her snort, they have found no other damage to her superstructure, hydroplanes, propellers, rudder or asdic dome. Her fore hatch is securely shut, and so is the after escape hatch. Her internal tube caps are closed. The hydroplanes are set to rise. Her bridge telegraphs are at stop, but as she was on a war patrol they may have been disconnected at the start of the exercise.

The Naval Board of Inquiry has presented an Interim Report, and before final conclusions are drawn, the diving ship H.M.S. Reclaim is trying to get further evidence. This is proving difficult, mainly due to the list of the submarine. Work has been restricted recently because of bad weather.

As the House will know, the broken snort has been recovered and subjected to a series of metallurgical tests. These show that the metallurgical condition of some of its members is below standard and that some of the welding is not good. A critical examination is therefore being made of the snort tubes of the A Class submarines, and the same sort of defects have been revealed in the snort tubes of two other submarines. It has therefore been decided to replace the snort tubes of all A Class submarines, and the present ban on snorting will remain until this has been done and the submarines re-equipped. Opportunity is being taken to re-examine the design of the snort tubes to see whether improvements can be made.

As to salvage, the House will have concluded from what I said at the beginning of this answer, that diving conditions are hazardous and that it is extremely difficult to work at these depths. The effective weight of a flooded submarine is nearly 1,000 tons, and the prospects of successfully lifting that weight in stages through nearly 300 feet are not at all good. No final decision on salvage has yet been taken.

Mr. J. P. L. Thomas

The House will agree that the Parliamentary Secretary has made a most serious statement with regard to the deficiency in the snort apparatus. May I therefore ask him two questions? Can he give us an assurance that those responsible for examining all the vital equipment of this kind have available to them the most modern methods for detecting faults? May I ask him to promise the House that the Admiralty will conduct the most rigorous investigations into all possible causes of the defects in the snort tube? I am sure the House would wish me to express—this, I am sure, must be felt in all quarters—our admiration for the divers, and to pay our tribute to them for their gallantry and devotion to duty in what has been a very hazardous task?

Mr. Callaghan

Yes, Sir, the best equipment is available for purposes of inspection, but inspection is not applied to 100 per cent.; otherwise, we would have as many inspectors as workmen doing a particular job. As far as the second part of the question is concerned, certainly the Admiralty are now pursuing the whole history of the fabrication and manufacture of these snorts.

Commander Noble

In view of the fact that the Minister told us earlier this afternoon that we were going to transfer four submarines to France, can he say whether the fact that so many officers under training were on this occasion sent out in one submarine was due to shortage of submarines? If so, is this transfer really desirable?

Mr. Callaghan

No, Sir, it was not due to shortage of submarines. It is the normal practice to send that number of officers forming a complete team, out on a job of this sort.

Commander Maitland

Although the hon. Gentleman has told us that there is a defect in the snort metal, does his answer mean that no decision has been reached as to how the accident occurred? Can he assure the House that every effort will be made, quite irrespective of the defects in the metal, to find out how the accident occurred?

Mr. Callaghan

The hon. and gallant Member is quite right. I was careful not to conclude that the accident had been caused by a defect in the snort, as, I think, a perusal of my answer will show. It is the most obvious theory, but the reason why H.M.S. Reclaim is now trying to get further evidence is in order to confirm that theory or, alternatively, to open up a fresh series of thoughts on the subject.

Captain Ryder

Arising out of the hon. Gentleman's reply about the testing of this apparatus, may I ask whether, in cases where welding is used for very vital structure, it is not the practice to have these subjected to an X-ray test? Will the hon. Gentleman insist on the other snorts in future being subjected to this very vital and important test?

Mr. Callaghan

X-ray photography is used to test welds, but, as I have said, it is not applied 100 per cent. It has not been applied 100 per cent. in the past. Whether it should be so in the future in relation to snorts or any other parts of a ship's superstructure, is now a matter for consideration.

Sir Ian Fraser

As, judging from the hon. Gentleman's answer, no final decision has yet been taken as to whether an attempt is to be made to lift the submarine, will the Admiralty take into account not merely the interest in the lifting of the submarine to ascertain the full reason for the accident and to prevent its recurrence, but also the value of such a highly complicated technical exercise to all the skilled men who would be engaged in it? Having regard to the Parliamentary Secretary's remarks that there would be 1,000 tons weight, would that not be modified if it were possible to pump out the water?

Mr. Callaghan

The considerations which the hon. Member mentions are, of course, very much in our minds, but there are considerations on the other side also, as he will appreciate. I would rather not go into technicalities as to what the weight to be lifted would be if water were pumped out. I imagine that it would be less, for obvious reasons, but the difficulty of pumping the water out is one of the reasons, which I think, might lead to the reaching of the conclusion not to raise the submarine.

Mr. John Arbuthnot

Is there not a valve at the bottom of the snort tube so as to prevent damage to the snort tube alone causing a disaster such as this? Does the answer which the hon. Gentleman has given mean that the valve has gone wrong at the same time as the defect in the snort tube occurred?

Mr. Callaghan

The snort induction valve is there precisely for the purpose which the hon. Member indicates. That is one reason why H.M.S. Reclaim is now trying to get further evidence in order to confirm the theory that has been put forward.