"Seemed Like a Good Idea": American Subchasers in the Great War

Three Submarine Chasers in Port

The U.S. Navy employed a type of anti-submarine craft from which much was expected. These were the 70-ton, 110-foot wooden-hulled patrol boats with the evocative name of "submarine chasers." Outfitted with gasoline engines, they were armed with a single three-inch gun and a small number of depth charges. No fewer than 448 were ordered, and 303 took part in the war. Seventy-two were sent to Europe, equally divided between Plymouth and the Straits of Otranto in the Mediterranean. The French navy purchased 50 in 1917 and another 50 in 1918. They were armed with a 3-in Poole deck gun, racks of depth charges, a Y-gun launcher, and Lewis and Colt machine guns on the bridge wings. Below decks were a galley, an engine room, a radio room, quarters for two officers and a crew of over 20 men, fresh water tanks, and storage rooms. To achieve the technical specifications for speed, the chasers each had to be fitted with three enormous Standard 220-hp gasoline engines.

They never really fulfilled the hopes placed on them, however. They were too slow and too small to escort convoys, and, while able to withstand rough weather, could not make much headway in heavy seas. The gasoline fuel made them prone to fires. Admiral Sims admitted to a French officer that the United States was using them simply "because we have them." They had been designed before the difficulties of anti-submarine warfare were fully realized. On the other hand, the relatively unsophisticated nature of the boats made them well suited for amateur crews, called up for service from the Naval Reserve. 

Location of the Otranto Barrage

Those deployed at Otranto had a high proportion of college men and were dubbed the "Harvard-Yale Squadron." The "Otranto Barrage" was an Allied naval blockade of the Strait of Otranto between Brindisi in Italy and Corfu on the Greek side of the Adriatic Sea in the First World War. The blockade was intended to prevent the Austro-Hungarian Navy from escaping into the Mediterranean and threatening Allied operations there. The blockade was effective in preventing surface ships from escaping the Adriatic, but it had little or no effect on the submarines based at Cattaro.

At Otranto, the little boats worked in groups of three or four to exploit what was thought to be a war-winning invention, the hydrophone. It was believed, perhaps correctly, that the American listening devices were superior to anything developed by the Allies. In order to function effectively, the hydrophones required silence, with nearby ships stopping their engines so a submarine might be detected. Three of the "chasers" would then supposedly locate the enemy submarine by "triangulation." Another "chaser," or preferably a destroyer with more offensive firepower, would be on hand for the "kill." Their use in this manner conformed to Benson's desire that they act "offensively," but the commander at Otranto reported to Sims: "It has been very difficult to induce people to believe the safety of their vessels was enhanced by stopping them for set periods in waters traversed by enemy submarines." 

Subchaser SC-26 at Sea

The little "chasers" at Otranto conducted 37 submarine hunts and believed they had made 19 "kills." In fact, none could be confirmed. However, there is evidence that the subchasers hampered enemy U-boat activity. Hampering the progress of enemy submarines meant shortening their hunts, ideally preventing them from crossing the barrage lines entirely, but in any case slowing them down and forcing them to return to base with fewer days and hours in the shipping lanes. In fact, the numbers seem to bear out the effectiveness of the effort. As the barrage lines were fortified by chasers and other ASW craft, U-boat kills in the Mediterranean were significantly reduced.

Sources:  "The U.S. Navy in the Great War" by Paul Halpern, Relevance, Spring 2004; "U.S. Navy Submarine Chasers in the Great War" by Todd A. Woofenden at The Subchasers Archives.