The Victory At Sea

by William Sowden Sims; Burton Jesse Hendrick

THE OPTION OFFERED TO THE GERMAN SUBMARINES

This diagram explains why the American navy succeeded in transporting more than 2,000,000 American soldiers to France without loss because of submarines. The Atlantic was divided into two broad areas—shown by the shaded parts of the diagram. Through the northern area were sent practically all the merchant ships with supplies of food and materials for Europe. The southern area, extending roughly from the forty-fifth to the forty-ninth parallel, was used almost exclusively for troopships. The Germans could keep only eight or ten U-boats at the same time in the eastern Atlantic; they thus were forced to choose whether they should devote these boats to attacking mercantile or troop convoys. The text explains why, under these circumstances, they were compelled to use nearly all their forces against merchant ships and leave troop transports practically alone.

Up to the present moment this narrative has been concerned chiefly with the northernmost of these two great sea pathways. Through this one to the north passed practically all the merchant shipping which was destined for the Allies. Consequently, as I have described, it was the great hunting ground of the German submarines. I have thus far had little to say of the Bay of Biscay section because, until 1918, there was comparatively little activity in that part of the ocean. For every ship which sailed through this bay I suppose that there were at least 100 which came through the Irish Sea and the English Channel. In my first report to the Department I described the principal scene of submarine activity as the area of the Atlantic reaching from the French island of Ushant—which lies just westward of Brest—to the tip of Scotland, and that remained the chief scene of hostilities to the end. Along much of the coastline south of Brest the waters were so shallow that the submarines could operate only with difficulty; it was a long distance from the German bases; the shipping consisted largely of coastal convoys; much of this was the coal trade from England; it is therefore not surprising that the Germans contented themselves with now and then planting mines off the most important harbours. Since our enemy was able to maintain only eight or ten U-boats in the Atlantic at one time it would have been sheer waste of energy to have stationed them off the western coast of France. They would have put in their time to little purpose, and meanwhile the ships and cargoes which they were above all ambitious to destroy would have been safely finding their way into British ports.

The fact that we had these two separate areas and that these areas were so different in character was what made it possible to send our 2,000,000 soldiers to France without losing a single man. From March, 1918, to the conclusion of the war, the American and British navies were engaged in two distinct transportation operations. The shipment of food and munitions continued in 1918 as in 1917, and on an even larger scale. With the passing of time the mechanism of these mercantile convoys increased in efficiency, and by March, 1918, the management of this great transportation system had become almost automatic. Shipping from America came into British ports, it will be remembered, in two great "trunk lines," one of which ran through the English Channel and the other up the Irish Sea. But when the time came to bring over the American troops, we naturally selected the area to the south, both because it was necessary to send the troops to France and because we had here a great expanse of ocean which was relatively free of submarines. Our earliest troop shipments disembarked at St. Nazaire; later, when the great trans-Atlantic liners, both German and British, were pressed into service, we landed many tens of thousands at Brest; and all the largest French ports from Brest to Bordeaux took a share. A smaller number we sent to England, from which country they were transported across the Channel into France; when the demands became pressing, indeed, hardly a ship of any kind was sent to Europe without its quota of American soldiers; but, on the whole, the business of transportation in 1918 followed simple and well-defined lines. We sent mercantile convoys in what I may call the northern "lane" and troop convoys in the southern "lane." We kept both lines of traffic for the most part distinct; and this simple procedure offered to our German enemies a pretty problem.

For, I must repeat, the German navy could maintain in the open Atlantic an average of only about eight or ten of her efficient U-boats at one time. The German Admiralty thus had to answer this difficult question: Shall we use these submarines to attack mercantile convoys or to attack troop convoys? The submarine flotilla which was actively engaged was so small that it was absurd to think of sending half into each lane; the Germans must send most of their submarines against cargo ships or most of them against troopships. Which should it be? If it were decided to concentrate on mercantile vessels then the American armies, which the German chiefs had declared to their people could never get to the Western Front, would reach France and furnish General Foch the reserves with which he might crush the German armies before winter. If, on the other hand, the Germans should decide to concentrate on troopships, then the food and supplies which were essential to the Allied cause would flow at an even greater rate into Great Britain and thence to the European nations. Whether it were more important, in a military sense, to cut the Allies' commercial lines of communication or to sink troop transports is an interesting question. It is almost impossible for the Anglo-Saxon mind to consider this as a purely military matter, apart from the human factors involved. The sinking of a great transport, with 4,000 or 5,000 American boys on board, would have been a dreadful calamity and would have struck horror to the American people; it was something which the Navy was determined to prevent, and which we did prevent. Considered as a strictly military question, however—and that was the only consideration which influenced the Germans—it is hard to see how the loss of one transport, or even the loss of several, would have materially affected the course of the war. In judging the purely military results of such a tragedy, we must remember that the Allied armies were losing from 3,000 to 5,000 men a day; thus the sinking of an American transport once a week would not have particularly affected the course of the war. The destruction of merchant shipping in large quantities, however, represented the one way in which the Germans could win. There were at least a hundred merchant ships to every one of our troopships; if a considerable number of the former could be sunk, Germany would have scored a decisive advantage. From the declaration of submarine warfare, the objective of the German Admiralty had been for "tonnage"; by March, 1918, as already said, the chances of destroying sufficient tonnage to win had become extremely slight; yet it still represented the one logical mission of the submarine.

The two alternatives, however, that of attacking mercantile convoys or troop convoys, hardly existed in fact. Let us suppose for a moment that the Germans had changed their programme, had taken their group of operating submarines from the northern trade routes, and had stationed them to the south, in the track of the troop transports. What would the results have been? "Lane," though a convenient word for descriptive purposes, is hardly an accurate one; for this ocean passage-way was really about 200 miles wide. Imagine eight or ten submarines, stretched across that expanse and hunting for troopships. At this rate the Germans would have had about one submarine for every twenty miles. Instead of finding themselves sailing amid a swarm of surface ships, as they were when they were stationed in the busy trade routes of the Irish Sea or the English Channel, the submarines would have found themselves drifting on a great waste of waters. Our troop convoys averaged not more than three a week even in the busiest period; in all probability the submarines would therefore have hung around for a month without catching a glimpse of one. Even if by some chance the patient vigil should finally have been rewarded, it is extremely unlikely that the submarine would ever have found a favourable opportunity to attack. We must keep in mind that the convoy room at the Admiralty knew, within certain limits, the location of submarines from day to day; any time one was located in the track of a troop convoy, therefore, a wireless to the convoy would have conveyed this information and directed it to reach the coast of France by another route.

At the beginning the speediest vessels only were used for transporting troops. Ships which made less than twelve knots an hour were not deemed safe for such precious cargoes; when the need for troops became more and more pressing and when our transport service had demonstrated great skill in the work, a few slower vessels were used; but the great majority of our troop transports were those which made twelve knots or more. Now one of the greatest protections which a ship possesses against submarine attack is unquestionably high speed. A submarine makes only eight knots when submerged—and it must submerge immediately if its attack is to be successful. It must be within at least a mile of its quarry when it discharges its torpedo; and most successful attacks were made within three hundred yards. Now take a pencil and a piece of paper and figure out what must be the location of a submarine, having a speed of eight knots, when it sights a convoy, which makes twelve knots and more, if it hopes to approach near enough to launch a torpedo. A little diagramming will prove that the U-boat must be almost directly in line of its hoped-for victim if it is to score a hit. But even though the god of Chance should favour the enemy in this way, the likelihood of sinking its prey would still be very remote. Like all convoys, the troopships began zigzagging as soon as they entered the danger zone; and this in itself made it almost impossible for a submarine to get its bearings and take good aim. I believe that these circumstances in themselves—the comparative scarcity of troop transports, the width of the "lane" in which they travelled, the high speed which they maintained, and their constant zigzagging, would have defeated most of the attempts which the Germans could have made to torpedo them. Though I think that most of them would have reached their destinations unharmed without any other protection, still this risk, small as it was, could not be taken; and we therefore gave them one other protection greater than any of those which I have yet mentioned—the destroyer escort. A convoy of four or five large troopships would be surrounded by as many as ten or a dozen destroyers. Very properly, since they were carrying human cargoes, we gave them an escort at least three times as large per vessel as that given to large mercantile convoys of twenty or more vessels; and this fact made them very uninviting baits for the most venturesome U-boat commanders.

When the engineers build a Brooklyn bridge they introduce an element which they call the factor of safety. It is their usual procedure to estimate the greatest weight which their structure may be called upon to bear under any conceivable circumstances and then they make it strong enough to stand a number of times that weight. This additional strength is the "factor of safety"; it is never called into use, of course, but the consciousness that it exists gives the public a sense of security which it could obtain in no other way. We adopted a similar policy in transporting these millions of American boys to Europe. We also had a large margin of safety. We did not depend upon one precaution to assure the lives of our soldiers; we heaped one precautionary measure on another. From the embarking of the troops at New York or at Hampton Roads to the disembarkation at Brest, St. Nazaire, La Pallice, Bordeaux, or at one of their other destinations, not the minutest safeguard was omitted. We necessarily thus somewhat diminished the protection of some of the mercantile convoys—and properly so. This was done whenever the arrival of a troop convoy conflicted with the arrival of a merchant convoy. Also, until they reached the submarine zone, they were attended by a cruiser or a battleship whose business it was to protect them against a German raider which might possibly have made its escape into the ocean; the work performed by these ocean escorts, practically all of which were American, was for the most part unobtrusive and unspectacular, but it constitutes a particularly fine example of efficiency and seamanlike devotion. At Berehaven, Ireland, as described above, we had stationed three powerful American dreadnoughts, momentarily prepared to rush to the scene in case one of the great German battle-cruisers succeeded in breaking into the open sea. Even the most minute precautions were taken by the transports.

The soldiers and crews were not permitted to throw anything overboard which might betray the course of a convoy; the cook's refuse was dropped at a particular time and in a way that would furnish no clue to a lurking submarine; even a tin can, if thrown into the sea, was first pierced with holes to make sure that it would sink. Anyone who struck a match at night in the danger zone committed a punishable offence. It is thus apparent why the Germans never "landed" a single one of our transports. The records show only three or four cases in which even attempts were made to do this; and those few efforts were feeble and ineffectual. Of course, the boys all had exciting experiences with phantom submarines; indeed I don't suppose that there is a single one of our more than 2,000,000 troops who has not entertained his friends and relatives with accounts of torpedo streaks and schools of U-boats.

But the Germans made no concerted campaign against our transports; fundamental conditions, already described, rendered such an offensive hopeless; and the skill with which our transport service was organized and conducted likewise dissuaded them. I have always believed that the German Admiralty ordered their U-boat captains to let the American transports alone; or at least not to attack except under very favourable circumstances, and this belief is rather confirmed by a passage in General Ludendorff's memoirs. "From our previous experience of the submarine war," General Ludendorff writes, "I expected strong forces of Americans to come, but the rapidity with which they actually did arrive proved surprising. General von Cramon, the German military representative at the Austro-Hungarian Headquarters, often called me up and asked me to insist on the sinking of American troopships; public opinion in Austria-Hungary demanded it. Admiral von Holtzendorff could only reply that everything was being done to reduce enemy tonnage and to sink troopships. It was not possible to direct the submarines against troopships exclusively. They could approach the coasts of Europe anywhere between the north of England and Gibraltar, a front of some fourteen hundred nautical miles. It was impossible effectively to close this area by means of submarines. One could have concentrated them only on certain routes; but whether the troopships would choose the same routes at the same time was the question. As soon as the enemy heard of submarines anywhere he could always send the ships new orders by wireless and unload at another port. It was, therefore, not certain that by this method we should meet with a sufficient number of troopships. The destruction of the enemy's freight tonnage would then have been undertaken only spasmodically, and would have been set back in an undesirable manner; and in that way the submarine war would have become diverted from its original object. The submarine war against commerce was therefore continued with all the vigour possible."