At 8:40 they arrived off Durazzo, and stood by six miles from shore to await the arrival of the bombarding force. Its smoke could be seen on the horizon, and as the Italian vessels hove in sight, the sub-chasers moved to their stations.
Moving along on the flanks of the bombing squadrons, the chasers acted as a screen for the larger vessels, which poured out a rain of shells upon the Austrian defenses. Guarding the British Light-Cruiser Force, the three boats of Unit B had to run in close to shore, only 800 yards from the enemy batteries. They had a lively experience for fifteen or twenty minutes, shells falling around them. But, going at full speed and "zigzagging to beat the band," as the sailors say, they managed to escape unscathed.
Suddenly came the cry, "Submarine!" Sub-chaser 129 had sighted the moving feather of a U-boat about 1,600 yards off her port quarter. Signaling to S. C. 215, S. C. 129 altered her course to the left to deliver an attack at right angles. The U-boat was heading south, apparently getting in position to attack the bombarding forces. In a moment a second feather was sighted a little farther to westward. As S. C. 129 reached the supposed path of the undersea boat, a depth-bomb was dropped. When it exploded, the enemy submerged for almost a minute, and then reappeared, showing both periscopes. S. C. 129 immediately began laying a pattern of depth-charges ahead of the U-boat and at right angles to his course.
When the seventh bomb exploded, in the water thrown up objects resembling pieces of metal appeared, and there was another explosion, seemingly in the submarine. The chaser crew was confident that submarine was destroyed.
Sub-chaser 215, sighting another periscope 750 yards away, opened fire with her three-inch gun and port machine-gun, hoisting signal to form for attack. The second three-inch shot dropped within two feet of the periscope, the commanding officer reported, and shattered it, a column of water six feet high rising into the air. The U-boat seemed to be turning sharply to starboard in the direction of the British light cruisers, which were then entering their bombarding sector. S. C. 215 and S. C. 128 closed in on the submarine and laid a pattern of depth-charges. As the fourth charge exploded, the executive officer of S. C. 215 sang out, "That got him!" He had seen what appeared to be a ship's plate and debris rise to the surface and then disappear. Heavy oil rose, covering the water in the vicinity, and the chaser crews concluded the U-boat had been sunk.
S. C. 215 and S. C. 128 then turned and headed for S. C. 129, which had first reported sighting a "sub," but which was lying to, repairing her engines. The unit stood over to capture the Austrian hospital ship, hoisting the international flag, "Stop instantly!" The British cruisers Nereide and Ruby were, at the time, astern of the Austrian vessel, and the Nereide signaled that she would stop and take off the armed guard crew if the chasers wished to take over the hospital ship. The chasers, which were north of the Austrian port, replied that they would take her over when clear of Durazzo.
The little American craft took charge of the big Austrian vessel, the British cruisers Tribune and Shark, signaling, "Go to Brindisi." Reaching Brindisi, they released the hospital ship, which had been taken to port for investigation. Then, with a sense of duty well done, the chasers dropped anchor in the harbor, and "called it a day."
While Unit B enjoyed the most exciting experience, all the other units were busy doing their full share of the work, escorting the bombing vessels and playing their part in the bombardment. When the British cruiser Weymouth was torpedoed, Units D, C, and H went to her assistance, and aided in warding off further attack. Though damaged, the cruiser was safely navigated to port. The boats of Unit D got close enough to fire at the houses on Cape Laghi.
The attack on Durazzo was a decided success. The city was practically put out of business as a naval base, and was of little further use to the Austrians who, defeated on land and sea, soon sued for peace.
The United States naval base at Corfu, where thirty-six of our sub-chasers were stationed, was established May 24, 1918, by Captain R. H. Leigh, Commander of Submarine Chasers for Distant Service. The primary duty of our forces there was to patrol the Straits of Otranto, the entrance to the Adriatic. That narrow stretch of water, forty miles wide, from Corfu to the "heel" of Italy, was the only route by which Austrian and German vessels from Trieste, Fiume, Pola, and Durazzo could make their way into the Mediterranean.