A Naval History of World War I

by Paul G. Halpern

  There were other factors that played important roles in frustrating the U-boat campaign. These fall under what Admiral Hezlet termed the “immense skill” with which the Allies eventually organized their shipping and the flexibility of world shipping itself. These considerations included shorter turnarounds and alleviation of congestion in Allied ports, the reduction of imports to essentials, the concentration of ships on the relatively shorter North Atlantic routes as opposed to the longer voyages to South America and the Far East, and a whole range of measures that cannot be described here but that had the cumulative effect of greatly increasing the efficiency of the declining amount of tonnage available. The measures were supplemented by generally skillful diplomacy, which kept neutral shipping working for the Allies.100

  It would be an oversimplification of what really happened to assume that when the crisis of April 1917 forced the adoption of the convoy system, the Admiralty staff recognized its error, put every effort into making convoys work, and steadily checked the submarine menace. Unfortunately matters were not so clear to those in authority at the time. The Admiralty appears to have given only reluctant and grudging acceptance to the convoy system in the summer of 1917, even while it was proving itself. A staff officer later reported deletions of favorable remarks about the convoy system from weekly appreciations and a reluctance to start the outward-bound convoys, in the mistaken belief that outward-bound ships were being sunk because escorts had been detached to meet the homeward convoys.101

  The idea that “offensive” operations ought to be continued along with the merely “defensive” convoys also appears to have died hard. Considerable resources were still devoted to operations aimed at hunting submarines. At the very moment the first homeward convoys were being instituted in June, the Grand Fleet was ordered to mount a grandiose submarine-hunting operation with destroyers and submarines, designated Operation BB. The operation covered a vast area around the north of Scotland divided into five destroyer areas and four submarine areas. The areas were along known routes taken by U-boats, and the timing of the operation was based on Admiralty intelligence that a number of German submarines would be passing through between 15 and 24 June. The objective was to force the U-boats to dive through the areas occupied by destroyers, so they might then be on the surface when passing through the adjacent areas occupied by submarines. Operation BB employed no fewer than 4 flotilla leaders, 49 destroyers—about 34 on patrol each day—and 17 submarines. The operation had priority over all other operations. Admiral Bayly’s requests for destroyer reinforcements to meet the incoming convoys from North America were denied. The destroyers represented about 56 percent of the Grand Fleet’s destroyers. Beatty wrote his wife that he had denuded himself of all destroyers, submarines, patrol vessels, seaplanes, and airships and that the fleet “is immobilised for the time being.” However, he justified it: “It’s no use pecking at it and have taken the largest steps I can.”102

  The results of this colossal effort were disappointing. During the eleven days of Operation BB, 12 homeward-bound and 7 outward-bound U-boats proceeded in and out of the North Sea while another 5 were working on the Bergen-Lerwick route. There were probably 15 submarines that passed through the hunting area east of the Shetlands, but after 26 sighting reports and 8 attacks by destroyers and 3 by submarines, the only tangible contact took place in the area east of Fair Island when a torpedo fired by the submarine K.1 hit the homeward-bound U.95 but failed to explode. The postwar naval staff study admitted that there was no evidence on the German side to indicate the passage of U-boats had been seriously interrupted.

  The British seemed slow to realize the futility of Operation BB. Beatty was optimistic and reported that the operation as regards the actual destruction of submarines was unsuccessful, but indirectly it may have harried the enemy and it undoubtedly prevented heavy losses in shipping on the Lerwick-Bergen route. Beatty recommended that in future operations of this sort a larger number of destroyers should be concentrated in fewer areas. The director of the Anti-Submarine Division at the Admiralty, Captain W. W. Fisher, believed that if the entire force had been concentrated in one area there would have been a definite success and recommended a similar operation when ships and fuel were available. Jellicoe agreed the operation should be repeated when the dispositions of the fleet would permit.103

  The great problem with an operation like BB in the eyes of the Admiralty staff was that the destroyers had to operate too far away from the fleet. A similar operation was not mounted until October. In the meantime the Grand Fleet executed a much more modest, but interesting, operation. Operation CC took place on 5–9 July when six of the Grand Flee’s destroyers patrolled a suspected German submarine route approximately 60 miles north of Muckle Flugga in the Shetlands. Five of the destroyers were equipped with kite balloons, and with excellent weather and visibility the observers in the balloons sighted a submarine. Unfortunately, despite their best efforts, when the destroyers attempted to hunt the submarine, they could not locate it, and with their fuel running low the force returned to Scapa with nothing but valuable experience in balloon work.104

  Beatty’s frustration at hunting submarines was expressed in a letter to his wife on 7 July:

  Our luck has been very bad. Every day we are within an ace of success, sometimes in two & even three places, but they can’t quite pull it off. . . .

  . . . It is a prodigious job, as it is like looking for a needle in a bundle of hay, and, when you have found it, trying to strike it with another needle. But we must stick to it, and I am sure the answer to the conundrum will be found, and also found quite a simple one. In the meantime it is very disheartening for everyone, who are as keen as mustard, and all do their best.105

  The major antisubmarine action by the Grand Fleet was designated Operation HS and took place on Admiralty orders when intelligence indicated that an exceptionally large number of German submarines were operating in the Atlantic and that three or four would be returning through the North Sea to their bases about 1–8 October. The general plan was to focus activity in four areas along the assumed homeward track, which extended approximately 300 miles between 59° 30’ N and 54° N and 0° 30’ E and 4° E. The southernmost area, roughly 150 miles from Harwich, was to be patrolled by destroyers from the Harwich Force. A mine-net barrage was laid in the northern end of the next area to the north, between the latitudes of the Firth of Forth and Flamborough Head. The barrage was patrolled by 16 armed trawlers, equipped with hydrophones, and the senior officer in the armed yacht Gossia. The trawlers hoped to edge submarines into the net. There also were 4 destroyers on patrol in the area. The next area to the north, between the latitudes of the Moray Firth and the Firth of Forth, was patrolled by 2 leaders and 14 destroyers from the Grand Fleet along with the armed yacht Shemara. The northernmost area was watched by submarines from the Grand Fleet flotillas, 4 on patrol at a time. Operation HS required sizable forces: 42 net drifters, 24 armed trawlers, 21 destroyers, a flotilla leader, and 4 submarines. Moreover, in order to maintain the destroyers and leaders at the required strength, Beatty had to detach 15 to 29 destroyers and leaders, and Harwich contributed 18.

  Approximately 22 miles of nets were laid in a somewhat irregular fashion on 1 October. The destroyers and submarines were on patrol, with gaps, from 27 September to 10 October. The destroyers did not see any submarines, and the weather was so bad that at one point the high seas made it dangerous for them to put their helm over. They were forced to shelter at various intervals, and a patrol was only maintained about 10 days out of 15, or 60 percent of the time. The storm-battered trawlers occasionally heard suspicious noises. And there were a number of explosions—some probably mines that had fouled the nets, but some fairly positive contacts that led to depth-charge attacks. The operation ended when the weather damaged the mines and nets to the point where they were no longer a menace to submarines. The DNI later reported three U-boats had been accounted for, citing U.50, U.66, and U.106. He was only partially correct.
These boats had been sunk, but subsequent research has revealed they were sunk farther to the south in other minefields. The Admiralty were encouraged and prepared to effect a similar operation in the spring.106 Their evaluation was, of course, wrong. Operation HS, like Operation BB a few months before, and despite the persistent efforts of the men in the small ships during the appalling weather, had not been worth the considerable efforts devoted to it.

  On the German side, the confidence of the high command began to wane as the date the Admiralstab had confidently predicted would see the collapse of Britain approached. They now began to qualify their former extravagant claims on behalf of unrestricted submarine warfare. In early July Ludendorff declared, in agreement with Holtzendorff, that he was confident of the effect of the submarine campaign but that it was impossible to specify an exact date on which Britain would collapse. When the British would submit was not solely dependent on the U-boat war but to a large degree on the will of the German people to hold out, and the realization this will was unbroken and unshakable. Hindenburg on 19 June advised Chancellor Bethmann Hollweg that he was certain submarines would eventually force the Entente to seek peace, but he could not say exactly when. The common belief the war would be over by the autumn was dangerous, and it was time to enlighten the public of the true situation.107 The German high command was in danger of becoming a victim of its own propaganda.

  The Germans missed the opportunity for a tactical innovation that might have partially offset the advantage the British gained with the convoy system. At the beginning of April the F.d.U. of the High Sea Fleet, Fregattenkapitän Bauer, proposed converting U.155, the former merchant submarine Deutschland, into a radio command boat in which the F.d.U. or his representative would proceed to the western portion of the blockade zone and by means of experienced wireless personnel analyze intercepted wireless traffic to gain intelligence on the approach of convoys, alterations in their routes, and the movements of antisubmarine escorts. U.155 would then use its wireless to direct U-boats to advantageous positions. The Admiralstab, however, ordered U.155 to the Azores.108 These large submarines proved clumsy to handle, and notwithstanding their great endurance, a disappointment. They could and did carry the war to the coast of North America, the Azores, and the African coast off Dakar, where they encountered less danger from escorts. However, this had to be balanced by the longer passages to and from their station and the smaller amount of traffic they encountered. The restricted number of U-cruisers available was also too small to really spread terror off the American coast. Captain Michelsen, the former commander of submarines, estimated that when the time required by refits was included in their calculations, one would have been able to obtain twice the results in British waters with smaller boats, fewer men, and less expenditure of effort.109

  The success of the convoy system led the Germans in early October to begin shifting U-boat operations from the Western Approaches to inshore waters in the Irish Sea, English Channel, Bristol Channel, and other coastal waters. Ships continued to sail independently in these waters when bound for either convoy-assembly ports for outward convoys or their home ports after homeward convoys had been dispersed. In the last three months of 1917, 33 percent of the ships lost to U-boats were ships proceeding independently from their port of embarkation to outward-convoy assembly ports, and 40 percent of losses were ships proceeding independently from convoy-dispersal points to their ports of disembarkation. The loss rate for ships sailing independently in coastal waters was estimated to be ten times that of ships in convoys.110

  The losses forced the British to abandon the outward convoy from Queenstown because of the danger to ships proceeding there through the Irish Sea. They hastened completion of the defenses of Lamlash, which became a port of assembly for ships from Liverpool and the Clyde. However, in 1918, persistent losses to ships proceeding from Liverpool to Lamlash led to convoys being assembled at Liverpool and sailing directly from Liverpool. Lamlash remained merely for Clyde traffic except when the absence of submarine activity in the Irish Sea permitted its use, which would economize on escorts. A system of daylight sailings with “ports of refuge” was also established in 1918 along the south coast for traffic between Folkestone gate and the outward-convoy assembly points at Devonport and Falmouth. As for the east coast, after 20 January 1918, the Scandinavian convoys assembled off Methil in the Firth of Forth and were escorted directly to Norwegian waters.111 Unfortunately, from January to May only a proportion of shipping on the east coast was in convoy, and the losses were high. From June until the end of the war, the proportion of shipping in convoy was increased until by the end of the war almost all traffic had been included in convoys.112

  On 22 November 1917, the Germans expanded their prohibited zone, where shipping could be torpedoed without warning, to 30° W in the Atlantic and established a new zone around the Azores. The latter was extended eastward on 11 January 1918, when the Germans also proclaimed a prohibited zone off most of the east coast of North America and from west of the Cape Verde Islands to Dakar and the west coast of Africa. They wanted to take advantage of the longer range of the U-cruisers to attack shipping off the Azores, which had become an important staging point for traffic to the Mediterranean, where the neutral channel to Greece was also closed. The Germans hoped their extension of the Atlantic zone to 30° W would provide more opportunities for submarines to attack and thin out the protection that could be given by the available escorts.113

  Would the Germans have enough submarines to make their expanded blockade effective? The realization the war would not end quickly had resulted in orders for an additional 95 U-boats in June 1917, but shortages of labor and material and other production difficulties as well as the recalcitrance of the War Office to give submarine construction the priority the navy demanded made fulfillment of the program slower than desirable. In November Scheer began pressing for the creation of a central authority under the Admiralstab empowered to surmount the difficulties. The normal channels of organization within the past few months had proved insufficient. He argued that the U-boat war had entered a critical stage and the convoy system had restricted German opportunities. Experienced commanders were being lost, new ones could not initially replace them adequately, and the reduction in U-boat effectiveness could only be offset by increasing the numbers of U-boats available for the submarine campaign. The problem was compounded by Ludendorff’s refusal on the question of providing labor to go any further than he had promised in the past. The army was finding it difficult to reduce losses in its own labor force, and its armaments program would not be reduced.

  To attack some of these problems the U-boat Office was established on 5 December 1917 under Vice Admiral Ritter von Mann, who was directly responsible to the state secretary of the Reichsmarineamt and charged with accelerating production and delivery of submarines. The 1919 program was decided a few days later and represented a sharp increase over the original proposals for 78 boats of all types. There would now be no fewer than 120 U-boats: 36 UB.III class (UB.170 to UB.205), 34 UC.III class (UC.119 to UC.152), 12 Ms class (U.201 to U.212), 18 U-cruisers (U.183 to U.200), and 20 UF class (UF.1 to UF.20). The latter were a new class suggested by the commander of the Flanders U-boat Flotilla and designed to operate in the English Channel and North Sea. Although the Germans did not realize it at the time, it was really too late. None of the boats in the 1919 program were ever finished; the handful that had been started before the end of the war were scrapped on the stocks.114

  GERMAN SURFACE RAIDERS

  The huge losses caused by the unrestricted submarine offensive far overshadowed the losses caused by German surface raiders. However, the threat from raiders had never really ceased and caused appreciable losses to the dwindling Allied tonnage and forced them to devote considerable resources to counter it.115 Two months before the start of unrestricted submarine warfare the Möwe sailed on her second cruise from Kiel on 23 November 1916 under the command of Korvettenkapitän Graf zu Dohna-Schlodien. The rai
der disguised herself as a Swedish steamer before passing through the Little Belt into the North Sea, and on 26 November intercepted and partially deciphered wireless messages arranging a rendezvous between the auxiliary cruisers Artois and Moldavia of the Tenth Cruiser Squadron in the Iceland-Faeroe gap. The Möwe had been heading right toward them and was now able to avoid the patrols and pass into the Atlantic to operate against the North American trade routes.

  The Möwe sank her first ship on the 30th, but on 4 December encountered the Belgian relief ship Samland, which had a safe conduct from the German embassy. Dohna was obligated to let the ship proceed unharmed, but ordered her wireless to be smashed. He gained only a slight respite, for three days later the Samland arrived at Falmouth and the Admiralty had definite news a raider was at large. The Admiralty responded by ordering troop transports at Dakar, the Cape, and Sierra Leone to remain in harbor until further notice while cruisers and auxiliary cruisers patrolled the trade routes in the North and South Atlantic. The numbers involved were substantial, approximately 24 British cruisers and auxiliary cruisers and an undetermined number of French cruisers. The efforts did not stop the Möwe, and the raider eventually proceeded to the south after transferring 400 prisoners to the captured British steamer Yarrowdale (4,652 tons) on 12 December. The German prize crew eventually managed to reach Germany.

  Dohna repeated the practice of earlier German raiders by coaling from the 7,000 tons available in the St. Theodore (4,992 tons) and subsequently arming her, installing a wireless set and turning the prize into the auxiliary cruiser Geier with orders to operate against the sailing ship route between Cape Horn and Europe. The Geier’s primary mission, however, remained to serve as a collier for the Möwe, and various rendezvous were arranged before the Geier, with engines and boilers in need of repair, was finally scuttled on 14 February. Her month and a half career as a raider was not spectacular; she sank only two sailing ships representing about 1,442 tons.