On the Bottom: The Raising of the Submarine S-51

by Edward Ellsberg

  But if the submarine was to come up one end at a time, there would be a period during which the boat would lie at an angle of thirty degrees, with her stem in the mud and her stern at the surface. In that position, all our pontoon chains would slip up the hull under the pull of the buoyant pontoons and would float away, letting the boat sink again. To prevent such a catastrophe, it was necessary to lash each pair of pontoons to the submarine so that when the stern came up, the pontoons would still stay where they belonged while we lightened up the bow till it also floated. We intended to bring her up stern first and designed all the lashings with that in view, but recognizing that there might be a slip, we also decided to provide a few lashings to prevent the pontoons from sliding forward off the bow, during the long tow to New York.

  But before we could do any lashing, it was necessary to float all the pontoons off the bottom into their lifting positions, which meant the pontoons must float just above the deck on each side of the submarine; the cradle chains would then be heaved taut under the hull by the pull of the pontoons.

  The end of May found us engaged in this task. Memorial Day came round. The weather was rough but diving was possible, and we dived. We forgot it was a holiday, till shortly before noon a small ship, the Triton, stood down from the northward towards us and circled under our stern. We hoisted our colors and half-masted them. The Triton passed close aboard, flung flowers and wreaths into the water as she swung slowly over the spot where lay the S-51. Several black-clad women, leaning over the Triton’s rail, wept as the bugler sounded “Taps.” A moment later one of them was carried below unconscious. Her husband lay with his shipmates, inside the motor room of the submarine. Sympathetically, we gazed after those to whom the S-51 meant more than a ship’s name, till the Triton disappeared over the horizon, then turned once more to our diving.

  We lay that night in the moorings. The weather report was fair, the sea calm. But weather off Point Judith follows no settled rules. By midnight it was blowing hard; by three A.M. it was blowing a gale.

  Lieutenant Hartley slacked his moorings, allowed the Falcon to head into the sea. He dared not put over a boat to unshackle the buoys in that storm. A half mile away, the Vestal rode to long scope, rolling heavily. The S-50 got underway for the Harbor of Refuge. The Sagamore, anchored to leeward, was pitching like a cork; the Iuka, anchored to windward, was behaving likewise.

  Through the darkness came the scream of a siren,—rising sharply, falling away to a moan. The lights of the Iuka were rapidly getting closer; she was dragging down in the gale.

  On the Falcon, the shrilling of the boatswain’s pipe brought the watch. A hoarse order from Hartley:

  “Stand by each mooring line with an ax!”

  The Iuka swept closer. Down the teeth of the gale we caught the rumble of a chain,—the Iuka was letting go her sheet anchor. No use; she dragged two anchors as easily as one. Resistlessly she came on, rising and falling sharply as the waves rolled by her. She loomed up not fifty feet from our bow, her lights gleaming through the storm, her siren shrieking out a warning; two more surges in that seaway and she would smash down on the diving ship.

  Hartley’s voice rose above the din of storm and siren:

  “Cut the hawsers!”

  Seven axes flashed through the darkness onto the heavy manila cables stretched out across the Falcon’s rails. Strands parted as the steel buried itself in the hemp. One blow on each hawser was enough. The remaining strands snapped, the broken cables jerked from our side. The Falcon shot down the wind, and in a few seconds was a hundred yards to leeward of the Iuka. Clear of the mooring buoys, we dropped anchor to ride out the storm.

  Meantime the Iuka stopped dragging and remained practically in the spot the Falcon had just vacated, a strange thing to happen as the storm kept increasing. Nevertheless there she remained, while all the other ships dragged slowly to leeward.

  Morning came, the gale howled on. We watched the sea, a tumbled mass of huge waves and flying spray, while the wind whistled through our rigging and our vessels tossed wildly in the sea. The radio told us of ships driven ashore all up and down the coast. We thanked our luck that we were well off shore and safe and as the foaming crests swept by our sides, congratulated ourselves on having sunk our last pontoon before the storm hit us.

  The day went slowly by. No chance to work at anything. I braced myself in my bunk, grasped the chance, the first in months, to read and rest. I had a new book, presented by a friend just before the expedition sailed. I hauled it off the shelf, opened it for the first time.

  On the flyleaf was written:

  “When the weather is too rough for sub raising, you may find this book interesting!”

  I plunged into the story of “Beau Geste.” The donor was right. In a few moments, I was far away from ship, storm, and submarine. In the middle of the burning African desert before Fort Zinderneuf I followed Beau Geste, and not till the mystery of the disappearance of the “Blue Water” was explained (which point I reached at two A.M.) did I suddenly return from Africa to my heaving bunk.

  The worst gale we ever experienced finally blew itself out. The Vestal literally had the paint blown off her topmasts. Our airhoses, which we left buoyed off from the pontoons, were a tangled mass, but worst of all the Iuka found she could not lift her anchor and get clear of the spot where she had so securely ridden the gale. She finally had to slip her anchor cable in order to get free.

  On the Falcon, we had a job to do before we could resume work. All the mooring hawsers which we had cut to dodge the Iuka were hanging from the mooring buoys, ruined. We had to fish up the ends attached to the buoys, remove the pelican hooks, and reeve off a new set of eight-inch hawsers. We were not willing to splice the old hawsers and trust them to hold the Falcon for diving.

  When after two days’ work, we finally steamed over the wreck, moored, and sent down Michels to inspect, we also found conditions in a mess below. The Iuka’s anchor was jammed in between the port forward pontoon and the hull of the submarine; the Iuka’s anchor chain was looped around the pontoon and from there led aft where it was tangled in the conning tower and finally was draped down the starboard side where the bitter end lay in the mud. Michels cleared the chain from the bridge and tied a line to it; we hauled up the free end, but in spite of all our heaving, we were no more able to get the anchor up than the Iuka had been.

  George Anderson dived with a crowbar and a four-inch line. He bent the line to the chain; we heaved first forward, then aft on the line under his directions and at last managed to get the chain clear and leading up and down, but the anchor would not drag free. It took a strenuous effort with the crowbar by Anderson to trip the flukes and a desperate struggle by which he wedged himself under the bilge of the pontoon to secure his line around the crown of the anchor, before we were able to drag the anchor out with the line and heave it up on the cable. Then we were ready once more to work.

  The struggle was too much for Anderson, however. He had been feeling none too well for weeks. Now, threatened with pneumonia, he had to be sent ashore for observation and treatment.

  The weather turned bad again, and from June 1 to June 9, we were unable to dive. But finally it calmed, and we entered the last stage of the job,—lashing the pontoons.

  If we had thought the pontoons were troublesome to handle before, we now found our former pontoon difficulties were mere trifles compared to those we daily encountered in the lashing process. To lash the pontoons, we had first to get each pair afloat over the submarine.

  We secured two hoses to each pontoon, one hose to each compartment. In the leveling process, we took a pair of pontoons at a time, blew air into both ends of both pontoons simultaneously and as evenly as possible. We supposed both pontoons, when slightly buoyant, would float up horizontally alongside the submarine till the chains stretched taut and stopped them.

  Actually, what happened was far different. We started in to level off the pontoons abreast the first tunnel. In spite of Niedermair’s be
st care, it was found impossible to blow evenly through four hoses at once. The forward end of the starboard pontoon got light before the others; that end rose. As it lifted off the bottom, the water pressure on it decreased a bit, the air inside expended and blew out more water, lightening the compartment still more and sending it up faster. Before we, on the surface, could stop blowing, that pontoon was standing vertically, forward end up, after end flat on the bottom. The high end dragged all the slack chain through under the submarine from the corresponding half of its mate pontoon on the opposite of the boat, preventing that pontoon from rising horizontally, even if it wanted to, which it never did, for it also rose vertically, but with its after end up.

  Considering the nerve-racking time we had had in getting the pontoons down, it was nearly a knockout punch to learn that they would not level off so we could lash them. We broke several six-inch manila hawsers trying to lay out horizontally the up-ended pontoons, but could not tip the huge cylinders over. Finally we did it by lightening the bottom ends till they capsized,—a process which did not add to our peace of mind for fear that the pontoons might fall against the submarine and smash it in.

  We got them flat again, flooded both pontoons completely to make sure everything was equal, and tried it over, but with the same result. Once more we tipped the pontoons, and I looked around for a new method of leveling off.

  We tried the following scheme next. Eadie went down on the starboard pontoon, and shackled a strong wire hawser to the lifting pad at each end. Then he came up. On the Falcon we took the wire hawsers over our side to the capstans. As a trial we heaved in till each wire had a good strain on it, about ten tons, but of course this failed to budge the pontoon, which weighed forty tons. We eased off the wires till they were slack.

  Niedermair then blew both ends of the starboard pontoon together. Every few minutes he stopped blowing and we heaved on the wires. After the fourth blow, we were just able with a pull of about ten tons on each wire, to lift the partly lightened pontoon off the bottom.

  When this happened, we blew no more, but lifted slowly on both lines till the marks on the wires showed we had lifted the pontoon about twenty feet, at which time it was hanging just above the submarine’s deck. At that point we ceased hauling and left the pontoon hanging suspended from our side. This placed a considerable strain on the wires, for on every up roll, the wires received quite a jerk, but it was unavoidable.

  Part two of the process was then started. Niedermair turned the air on both ends of the opposite pontoon, which still lay on the bottom, and blew steadily till one end, which turned out to be the after end, started to rise. It floated up, leaving the forward end still in the mud; but this time, when the pontoon reached an angle of about forty-five degrees, the light end brought up with a jolt on the chain through its after hawsepipe and was unable to rise further, since there was no slack chain obtainable from the other side of the boat. Niedermair continued to blow, but to the forward end only, and shortly that end also floated up till it was halted by the chain in the forward hawsepipe. The port pontoon was now floating horizontally above the submarine on its own buoyancy, and tugging on the chains which ran through the tunnel to the other pontoon. Niedermair ceased blowing.

  The strains on our wires to the starboard pontoon were now much increased, for in addition to the weight of that pontoon, there was added the buoyant pull on the chains from the opposite side. With every roll, it seemed certain the wires must let go or our capstans tear away. We hastened to finish the operation.

  Niedermair started blowing again, this time into the starboard pontoon which hung from our wires. As he expelled water from it, the strains on the wires gradually lessened. Soon the pontoon was itself buoyant,—the wires quit tugging and when slacked off a little, remained slack. Both pontoons were floating evenly in position above the submarine, ready to be lashed.

  On the Falcon, things brightened up considerably; the new scheme had worked. If we broke no wires in the process, all would be well, though it was obvious that we needed better weather for leveling off than we had needed for lowering or the wires would promptly snap.

  We repeated our leveling-off method on the midships pair of pontoons, the pair abreast the conning tower, with good results. Then to lighten up the submarine, we blew this pair of pontoons completely dry, giving them their maximum lift of one hundred and sixty tons. The engine room and the motor room were also dry, as were the port side ballast tanks. These ballasts had been blown partly dry by Wilson inside the control room the winter before, using the S-51’s own compressed air; the job had later been finished by Michels from the outside of the boat. Michels had used a fire hose to wash down under the port bilge keel till he came to the open Kingston valves in the shell; then he had inserted an airhose through the Kingstons and blown air up into the ballast tanks, meanwhile expelling water through the Kingstons, till the tanks were empty.

  I had hoped that with two pontoons lifting amidships, two stern compartments dry, and the port side ballast tanks dry and tending to roll the boat to starboard, that the S-51, which lay with an eleven-degree port list, would straighten up. As she lay, tightly buried in the clay, she was gripped by a suction force far greater than her weight. The S-51 weighed one thousand tons, but the suction holding her to the bottom was about eight thousand tons, a force so large we could never hope to overcome it by a direct lift. I hoped to get around this and break the suction by letting water in between hull and clay in two ways,—first by rolling the boat to starboard, and second by lifting her one end (stern) first.

  The difficulty is easily demonstrated. If a flat plate is placed on a smooth table top with a film of water between to exclude air, it will be found impossible to lift the plate straight up off the table. However, if one edge of the plate is grasped and lifted ever so slightly, air works its way under, breaks the suction, and the plate comes away easily.

  A similar condition, except that the force to be overcome was six times as much per square inch, and was spread over a vastly greater area, the whole bottom of the ship, existed on the S-51. This suction, amounting to eight thousand tons, was the one unknown we had to deal with, and it lay in the back of my mind always as a constant dread, that we might not be able to break the suction and lift the boat. The fear was well founded in fact; some partly buried torpedoes that our war vessels had lost in years before had broken in half under a heavy pull rather than come out of the mud; and some ten years before the British had had two different experiences where, in shallow water, they had been wholly unable to drag two small but partly buried submarines clear of the bottom, and those boats are there yet. We had a submarine far larger, and a suction many times greater, to deal with.

  Wilson and Eadie dived to measure off lashings for the second pair of pontoons. Hanging over the sides of the boat, they stretched small manila lines across the deck between the chains on the starboard and port pontoons,—one line on the forward chain, one line on the after chain. They sent up the lines cut to proper lengths, and while we on the Falcon made up sections of wire hawsers with eyes in both ends to suit their measurements, the divers attached strong steel clamps to the chains just under the floating pontoons.

  Eiben and Michels went down after them to measure off the lashings for the midships (or third) pair of pontoons, which floated abreast the conning tower. On the submarine, Eiben went to the starboard side with one end of a small measuring line. Michels, on the port side, took the other end of the line and walked slowly aft through the water between the port pontoon and the conning tower. As the boat lay heeled to port, the pontoon was fairly close to the submarine. Michels walked between the two, the pontoon looming almost as large as the submarine. Abreast the conning tower he paused a moment, peering through one of the eyeports out of curiosity. It was black inside, he saw nothing, but while he looked, he felt a strong push shoving him against the tower. At the bottom of the sea, that is disconcerting. Startled, he jumped sideways, clear of the tower, then stopped as he remembered Joe E
iben was down with him. He looked around to see why Joe had pushed him. There was no one in sight. And then his blood froze as he saw that the pontoon, which he had thought as immovable as the submarine, was swaying irregularly in and out like a huge inverted pendulum, occasionally crunching against the conning tower. And he had been in between! If that sweep he felt as a shove had been one of those wider swings he now watched, he would have been smashed in a huge nut cracker.

  Fascinated, he watched the swings of the pontoon as slowly and inexorably it swung in and out against the conning tower; though Michels did not know it, he was receiving the first definite proof of a much-disputed point in science,—that the effect of surface waves is felt far deeper in the sea than previously had been considered possible.

  Michels soon returned to normal; he had his job to do but wisely decided not to tempt the jaws of death again. He slipped over the side of the submarine, clinging to his line, and, keeping beneath the pontoon, stretched the lines over to the chains and marked off their lengths. Cautiously keeping low, he crept back on deck and clear of the superstructure where Eiben waited; together they started upward. On deck at last, Michels told what he had seen. All the divers were warned to keep out from between the pontoons.

  We finished making the wire lashings that night. They were heavy pieces of wire, which when stretched across the deck and clamped to the pontoon chains would form a loop completely encircling the submarine, and in connection with other lashings passed around the gun and the conning tower, would prevent the pontoons from sliding off the submarine, either forward or aft, while we were raising her.