VII Mod 2 Bliss-Leavitt Torpedoes…. By 1915 the effect of the European War, which threatened to involve the armament of the world, was being anticipated in America and the preparedness which was being talked about throughout the country was being actively practiced at the Torpedo Station…. Early in 1917 an open break with Germany was obvious and preparations were made at the Station to meet the emergency…. Station activities were further increased and the [civilian] working force enlarged to three thousand two hundred employees…. Navy personnel during the war numbered about thirteen hundred.23
Torpedoes, fired from surface ships as well as submarines during the Great War, were about to define the weaponry of twentieth-century naval warfare. A reminder is appropriate here: Soviet submarines dispatched to North American waters during the Cuban Missile Crisis in 1962 carried nuclear-tipped torpedoes.
ADMIRAL REINHARD SCHEER—PREDATOR
When the U-boat campaign was opened on February 1, 1917, there were 57 boats already in the North Sea. The officer commanding the Baltic district had eight assigned to him, the Naval Corps in Flanders had at its disposal 38, and the stations in the Mediterranean 31 boats of different types…. With this fleet of U-boats the Navy was well equipped to do justice to the task assigned to it, although England had used the whole of 1916 to develop her defense.24
Admiral Scheer, convinced of the predatory efficiency of Germany’s fleet of U-boats, became a proponent of a renewed dependency on submarine warfare early in 1917, in spite of the likely entry of the United States into the war (chapter 9). The two visits of Germany’s mercantile submarine Deutschland to American ports in 1916 (chapter 10) had provided credible evidence to Admiral Scheer that long-range operations were possible:
When they could no longer be used for trade purposes the commercial U-boats were taken over by the Navy and altered for use as warships. They were fitted with two guns of 15 cm. caliber and two torpedo tubes, and could carry about 30 torpedoes in accordance with the extended period during which they could be used on cruises …25
With significant firepower when on the surface or while submerged, the U-boat predators controlled the oceans. The images on pages 68 and 92 are examples of Germany’s cruiser submarines adopted after the successful trips of Deutschland. In response, drastic measures had to be put into place by the Admiralty—and quickly. Admiral Jellicoe devoted a chapter in his book The Grand Fleet, 1914-1916 to Britain’s early actions against German submarines.26
Referring to operations during 1915, Jellicoe expressed concern over the relative lack of success by the vessels Britain was using at the time, primarily destroyers. By that summer, several depth charge designs were being developed and carried by destroyers.
On July 1st the Hampshire reported that a torpedo had been fired at her in the Moray Firth. Twelve destroyers were sent to endeavour to locate and sink the submarine…. The boats exploded a large number of charges on the bottom in the hope of forcing any submarine to the surface.27
While there was no evidence that the above account resulted in the destruction of that U-boat, the prevailing strategy, besides ramming a surfaced submarine or dropping depth charges at its suspected location, was “to keep the submarine down long enough to cause her to exhaust her battery power, a period of some 48 hours.”28 There had also been accounts of British submarines finding and sinking a surfaced U-boat with a torpedo.29 Once submerged and free to maneuver at will, however, German submarines continued to be an elusive target.30
The solution was the hydrophone, though it would take more than two-and-a-half years, and America’s entry into the war, before this technology began to become a U-boat deterrent. Even by the end of 1916, according to Admiral Jellicoe, “[the] hydrophone had been in the experimental stage and under trial for a considerable period, but it had not so far developed into an effective instrument for locating submarines …”31 adding that … “all devices for use afloat suffered from the disadvantage that it was not possible to use them whilst the ship carrying them was moving … [the ship], when stopped, an easy target for the submarine’s torpedo.”32
Of all the weapons used in the anti-submarine war the two most important were the hydrophone and the depth charge. They were employed in conjunction with each other and comprised the surface warship’s principal means of offense against submarines operating beneath the surface.33
This assessment by Charles Domville-Fife, who commanded a British hydrophone flotilla during the Great War, underscored the significance of hydrophone detection, which would lead to a targeted location for the depth charges. Without the ability to provide a precise location of a submerged U-boat, however, dropping a barrage of depth charges was just a hit-or-miss attack. Perfecting the hydrophone would take time and resources. Early efforts within the British and French Admiralties were aided by their scientists and engineers who searched for ways to exploit the physics of underwater sound. Domville-Fife emphasized the importance of the hydrophone, which “enables the surface ship to discover, first, the presence of the submarine … and, secondly, its approximate location … When a surface ship is hot on the track of a moving submarine she endeavours to attain a position directly over the top of her quarry, or even a little ahead, and then releases one or more depth charges according to whether the chance of a hit is good or only poor.”34
The story of The Listeners begins with a single British officer assigned to a naval base in Scotland’s Firth of Forth. With a background in radio communication, Commander C. P. Ryan began experimenting with crude devices comprised of microphones housed in home-made, watertight containers. Ryan was soon able to hear, and distinguish from other vessels, the sound of a submarine. The technology continued to improve with significant advances occurring after America entered the war. The hunters, armed with an ample supply of depth charges, would soon have the tools they needed to detect, pursue, and destroy a German submarine—Admiral Scheer’s predators would become the prey.
CHAPTER 2 THE FIRTH OF FORTH
In January, 1915, Commander Ryan assembled a working party, the personnel of which consisted of half a dozen able seamen, and himself, with the result that the first authorized hydrophone was laid from Granton harbor [Edinburgh], from a small open boat. From this small beginning did the hydrophone service grow.
—Lieutenant H. W. Wilson, Hush, 19201
To supplement the current active duty naval forces, and in particular the need for officers and enlisted to deal with the submarine problem, the Admiralty relied on recalling its reserve forces and the return to service of the many officers who had recently resigned or retired. One of these retirees was Commander C. P. Ryan. He would initiate the first British efforts to investigate the use of underwater listening devices and create operational systems to detect submerged submarines, as described in a 1920 memoir by a member of his staff, Lieutenant H. W. Wilson, Royal Navy Volunteer Reserves (RNVR).
Beginning as a young midshipman in the 1890s, much of Ryan’s career during the early years of the twentieth century occurred in the Mediterranean, where he had become recognized for his “inventive genius” while commander of the destroyer HMS Zealous. Ryan recognized the military advantages brought to the fleet by Marconi’s wireless telegraphy, and in 1903 had submitted suggestions for improvements to the system, for which he received a commendation from the Admiralty. Ryan continued to pursue his interests in wireless technology, yet his peace-time service was uneventful, including his time on patrol in his home waters as commanding officer of the armored cruiser HMS Euryalus. After realizing that further advancements would not be forthcoming, Ryan retired in June, 1911, and joined the Marconi Company. Three years later, Ryan’s technological know-how would serve him well.2
Returning to naval service in August, 1914, Commander Ryan’s first assignment was the naval base on the Scottish island of Inchkeith in the Firth of Forth. He brought with him his