INVESTIGATION OF SINKING OF THE SUBMARINE "S-4"

WEDNESDAY, MAY 23, 1928

UNITED STATES SENATE,

SUBCOMMITTEE OF THE COMMITTEE ON NAVAL AFFAIRS,

Washington, D. C. The subcommittee met, pursuant to the call of the chairman, at .10.50 o'clock a. m. in the room of the committee in the Capitol, Senator Tasker L. Oddie presiding.

Present, Senators Tasker L. Oddie (chairman) and Peter G. Gerry. Present also, Commander J. H. Hoover, United States Navy, Mr. Spear, Mr. Lake, Mr. Davis, and Mr. Savoy.

Senator ODDIE. The committee will come to order. I will ask Mr. Spear to take the stand.

STATEMENT OF L. Y. SPEAR

Senator ODDIE. Mr. Spear, will you give your name, address, and occupation to the reporter?

Mr. SPEAR. L. Y. Spear, New London, Conn., vice president and technical head of the Electric Boat Co.; president of the New London Ship & Engine Co. By profession I am a naval architect and have specialized in the design and construction of submarines.

Senator ODDIE. Will you give us a brief statement of your technical training?

Mr. SPEAR. I graduated from Annapolis in the year 1890. After graduating I went to sea for two years and then went abroad to study naval architecture. I was transferred to the Construction Corps of the Navy and served in that organization for eight or nine years. I resigned from the service in 1902 and since that time have been continuously engaged in the design, construction, and operation of submarines. That is my main business.

Senator ODDIE. Are you familiar with the various safety devices in use on submarines in this country and in foreign countries and, in a general way, with those that have been suggested for use?

Mr. SPEAR. Yes.

Senator ODDIE. You have made a special life study of matters of that kind?

Mr. SPEAR. That has been my main business for the last 28 years. Senator ODDIE. Are you familiar with the subject of these hearings with regard to the sinking of the submarine S-4?

Mr. SPEAR. Yes; I am quite familiar with the S-4 case.

Senator ODDIE. We would like your candid opinion on the actions of the Navy in regard to the accident to the S-4 and in relation to its efficiency or any possible negligence in connection with the accident and especially in connection with its life-saving and salvage opera

tions and also in connection with the construction of submarines and safety appliances connected with them.

Mr. SPEAR. Let us begin with the construction first, then.
Senator ODDIE. Yes.

Mr. SPEAR. The S-4, as you no doubt know, was designed in 1916. The date of the design is quite old.

Senator ODDIE. Where was the S-4 built?

Mr. SPEAR. The S-4 was designed by the Navy Department and was built in the Portsmouth Navy Yard. It is a Governmentdesigned and Government-constructed boat entirely.

Senator ODDIE. Were you connected with the Navy at that time? Mr. SPEAR. No, sir; I was not.

Senator ODDIE. Were you consulted in any way in regard to the plans and specifications?

Mr. SPEAR. No; I had no connection whatsoever with the construction of the S-4.

Senator ODDIE. But you are familiar with it?

Mr. SPEAR. I am quite familiar with the design and construction of the S-4, but my company had no connection with it.

Senator ODDIE. Now, will you proceed, please.

Mr. SPEAR. I only wanted to bring out this fact, that the design is, so to speak out of date; it was designed in 1916.

Senator GERRY. When was she built?

Mr. SPEAR. She was laid down in 1917, or late in the fall of 1916; and I think she was about three years building two or three years. I have not the exact date in my mind, but I think she would have been completed in 1918 or 1919. She was designed in 1916. That was the first submarine that the Navy ever designed. All submarines in this country before that time were designed by private firms to meet the specifications and requirements issued by the Navy Depart

ment.

When that particular group of vessels was designed by the Navy Department the development of safety devices for submarines had not reached the point that it has reached to-day. In other words, if we were now to design a boat of this displacement it would be possible to-day to incorporate into the design devices that were not known at that time; and we could make a safer submarine, and one better able to withstand the damage that she suffered, and one which would afford much better opportunities for the escape or rescue of the men than was possible in 1916.

The progress made in the general subject is very great. It is more or less analagous to the progress that has been made in the development of airplanes and motor cars. So that, ton for ton, you can do a great deal more now than you could at the time those boats were laid down.

Broadly speaking, the S-4 had in her all of the recognized devices and safety features that were in common use at that time. I should say that she compared favorably with the general run of submarines designed at the same time that she was; but that she could not be considered at all equal with respect to safety to a submarine that we would design to-day of the same size.

So much for the matter of design. Now, with respect to the actual accident and the handling of the situation after the accident, my judgment is that

Senator GERRY. I would like to interrupt the witness just there, Mr. Chairman. I think while we are touching on this question of design we might go into it a little bit more fully. What would be the difference in modern design? Would the construction be stronger, or would there be added safety devices, or what?

Mr. SPEAR. Just this, Senator Gerry. Every part of the boat, starting even with the hull would be better built, because we know better how to build them. For instance we could build a hull for a boat of the same size as the S-4 which would weigh a great deal less than the S-4 hull does, and which would be equally strong, or we could build on the same weight a hull which would withstand considerably greater pressure. For instance, the S-4 was constructed for safe submergence to 200 feet. With the same weight of hull to-day we could build a boat that would be good for 50 per cent greater depth. That same thing runs all through the design in all the details. We are able to save weight and able to save space over what we could do then; and the consequence is that we have more margin after the military requirements are met to devote to those features which contribute to the safety of the boat, or the safety of the crew.

The biggest item of all I should say is hull design and construction, that is we gain more through that than we do in any other single item; but, at the same time, there has been great progress in all the innumerable things that go into a submarine; the special devices, and the machinery, and all those things. We can do a great deal more with the capital that is given to the designer to-day, supposing you call displacement the capital-we can produce the same military results and greater safety, or we can produce greater military results with the same safety.

There is one other point about design which perhaps I should bring out, and that is this, that the extent of the safety features that you can carry in a submarine depends to some extent upon the size of the boat. To illustrate this point, the size of apparatus designed to enable the crew to make their own escape from a sunken submarine depends fundamentally upon the size of a man. In proportion to a small boat, the size of the apparatus becomes relatively very great, in fact so great as to make the fitting of the apparatus impracticable because it would crowd out some absolutely essential military feature. But, when you build a boat ten or fifteen times as big as the small boat, the actual apparatus for the rescue of the men remains about the same size. Thus, relatively to your boat it becomes small and it is, therefore, possible in large submarines to incorporate safety features which it is not practicable to put into a small sub

marine.

In addition to the developments in detail of design of submarines the general tendency within the last few years has been to make them bigger and bigger. That increase in size is a help to the designer in incorporating safety features. For instance, in the earlier boats, the very early submarines, there were no bulkheads at all, and any injury to the hull that could not be handled by the pumps meant that the boat was going to sink. That was all there was to it. As the size increased we began to fit bulkheads so as to restrict the damage; and, at the time that the S-4 was designed we had reached the point where, broadly speaking, we could stand having one compartment broached to the sea and then if the ballast tanks were all

empty or could be emptied, the boat would still float. In our later designs of larger boats we can broach two compartments and the boat will still float.

The actual size of any given compartment is generally governed by some special consideration but as a general rule, as the boats increase in size, it is possible to make the compartment relatively shorter, therefore in the larger boats more bulkheads can be fitted. We also have greater relative ballast tank capacity than we used to have; and the net result is that with the very latest designs you can have a collision and broach two compartments and still your boat will float.

Senator GERRY. How many compartments did the S-4 have that would sustain her?

Mr. SPEAR. The S-4 had five separate water-tight compartments in the interior.

Senator GERRY. How many of those were needed to float her?

Mr. SPEAR. She was presumed to be designed so that any one of those might be filled, and if the ballast tanks were empty she would still float; but she could not stand to have two filled.

Senator GERRY. And in this collision two were filled?

Mr. SPEAR. In the collision one was filled immediately from the collision, and the water found its way through a ventilation valve in the battery ventilating system, into the second compartment, and filled that one.

Senator GERRY. And the second compartment was not really water-tight?

Mr. SPEAR. The water-tight bulkhead separating the two compartments was pierced by the ventilation duct to which I have just referred. A valve in this duct was fitted at the bulkhead in order to preserve its water-tightness, but apparently something went wrong with this valve so that the crew were unable to close it. The result was that the water flowed through from the broached compartment into the next compartment. So, that as the result of the accident, two compartments in the boat were flooded.

Senator GERRY. How long did it take to flood the second one? Mr. SPEAR. AS near as I can tell, Senator, from an estimate, taking into account the fact that the boat was sinking while the water was coming in-the first compartment would have flooded, with the hole that the Paulding made in her, in something between 50 and 60 seconds. That is, the first compartment would have flooded in that time. Now, the water probably began to get into the second compartment say in 30 or 40 seconds. The water had to rise to a certain height in the first compartment before it could pass through the ventilation duct into the second compartment. This duct was not designed to stand the high pressures to which it was subjected under these conditions, and it naturally ruptured under this high pressure. As it happened, the rupture occurred right over the switchboard and the result was that the live switches were deluged with salt water, resulting in short circuits, fusing, etc. Senator ODDIE. And gas, too?

Mr. SPEAR. And gas, too. And that, in my judgment, is what drove the men from that central compartment into the engine room. It was in this central compartment that all the controls for the ship were located. The means of blowing the ballast tanks, and of con

trolling all the apparatus that is used to control the weight of the boat, was located in this compartment from which the men were driven. This fact had a very distinct bearing on the result in this particular case.

Senator GERRY. How long do you think it took to flood the second compartment?

Mr. SPEAR. I have not made any figures on that, Senator.
Senator GERRY. Roughly?

Mr. SPEAR. As a rough guess, I would say that it did not take more than two minutes.

Senator GERRY. That is why she settled so quickly?

Mr. SPEAR. That is why she settled so quickly.

Senator GERRY. The ballast tanks were empty, were they?

Mr. SPEAR. No; her ballast tanks were all full. You see, the boat was in diving condition. In fact she was running submerged at the time with the main ballast tanks full and her other ballast tanks had the required amount of water for diving in them.

Senator GERRY. But she had just come up.

Mr. SPEAR. She had only risen to the surface-what they call planed up. You do not have to change weight to come up, but just set your rudders. A submarine steers up and down just as a surface craft steers to the right or left, and you do not necessarily have to eject water to come up.

Senator GERRY. With her ballast tanks in that condition, if she had not had the water in the second compartment would she still have floated?

Mr. SPEAR. If the water had not come into the second compartment, they could have blown all of the uninjured ballast tanks and also the fuel tanks, and the buoyancy so gained should have been sufficient to have kept her just afloat. On account of the damage due to the collision, one of the main ballast tanks could not have been blown because it was ruptured near the top. As a matter of fact, the crew attempted to blow the ballast tanks before they left the central compartment. All of the valves in the air manifold leading from the air supply to the main ballast tanks were found open, including the one leading to the injured tank. Thus there was a free connection between the air supply and the sea through the injured tank, which would naturally result in the loss of the whole of the ship's air supply.

It is obvious from what was found that the crew attempted, in the short space of time they had before they were driven from that compartment, to do the correct thing, which was to blow their ballast tanks.

Senator GERRY. And after that compartment was flooded, as you stated, the batteries were put out of commission.

Mr. SPEAR. That would not be instantaneous, Senator. There is no question but what they had voltage in the batteries, and lights burning in the ship for some time afterwards. It takes quite a little time for the battery to completely discharge itself under those conditions.

Senator GERRY. Had they been able to blow the tanks it would not have floated the ship with these two compartments flooded, would it? Mr. SPEAR. Not with two compartments flooded; no.