9 Anti-Submarine Tactics
From 'Action In Submarines' By A. Widder (1967)

Meanwhile, Britain was not idle in its efforts to combat the submarine. A special bureau was established in the Admiralty which asked for suggestions from the public as to how the U-boat could be beaten. Over the course of the war this bureau received and investigated some forty thousand such suggestions (some of them wildly impractical). Many were tested, but not a single one proved in the end to have merit.

At the beginning of the war the submarine had only to guard against the danger of ramming by, or gunfire from, surface ships; the danger of torpedoes from enemy submarines; and the danger of mines. There were no other countermeasures for use against submarines, though these alone were enough to account for more than a few.

Mines were a sinister risk. Often the submarine had no idea that it was cruising into danger from them. The British increased the size and number of their anti-submarine mine-fields, and later in the war the Germans often had to send numbers of minesweepers out to spend hours clearing a mine-free channel so that a single U-boat could make its way from port to the high seas.

The menace of mines is brought into clear focus with this recollection of a U-boat officer. With his submarine purring eneath the surface on the power of its electric motors,

'suddenly there is a scraping and an eerie scratching all along ur boat's side. We listen, holding our breath, and then it stops. We sigh and it comes on again, so we shut down the motor on that side to avoid entangling the mine mooring in he propeller. Most of the crew are in their bunks, but none sleep. They lie listening and staring at the eerie tapping on he side, like human fingers drumming a nervous tattoo. Then it is all quiet for a long time and at dawn we surface, gratefully viewing the warm, rosy color streaking the eastern sky. Again we all realize what pleasure it is to live and breathe."

In the early part of the war, though, a submerged submarine had little to fear from surface ships. On one occasion a British heavy cruiser, after successfully dodging a torpedo, followed the standard antisubmarine procedure: it turned and headed at full speed down the torpedo's wake in an effort to ram and sink the submarine. As British Admiral John R. Jellicoe later told an American naval officer, the water beneath the cruiser on that occasion was unusually clear, and

"there lay the enemy in full view of her pursuers, yet perfectly safe! The officers reported this to me in the presence of Rear Admiral Madden. "Wouldn't it have been fine,' said Madden, 'if they had had on board a mine so designed that, when dropped overboard, it would have exploded when it reached the depth at which the submarine was lying?'That remark," said Jellicoe, "gave us the germinal idea of the depth charge."

British ordnance specialists at once began efforts to develop the device, which was the first weapon exclusively intended for use against submarines. Contained in steel cylinders and actuated by detonators which could be set to explode at various depths, depth charges came into general use in 1916 and 1917 and were commonly known as ashcans, which they resembled. They could be rolled off the stern of the ship or fired from small launching guns, which sent them a hundred feet or more through the air.

Another contrivance designed to combat the submarine was the anti-submarine net, which could be strung across almost any restricted body of water. The most ambitious of these stretched entirely across the English Channel from Dover to Calais, a distance of some 20 miles. Though exasperating to construct and frequently carried away by storms, the Dover barrier, later festooned with mines as an additional hazard to U-boats, was at least partially effective.

The Germans constructed an anti-submarine net across a constricted passage in the Dardanelles to assist the Turks in preventing British submarines from entering the Sea of Marmara and reaching Constantinople. Made of 2½-inch steel mesh, the net extended from shore to shore and from the surface to the bottom, which at one place was 220 feet down. Attending the net, and ready to take action against any submarines it might snare, were Turkish motor launches and patrol boats.

Lt. E. C. Boyle's E-14 was the first British submarine to encounter the net, and it managed to bull its way through. In the process of bulling through, as the net bulged up and out before the E-14's bow, the submarine was pulled up from 80 feet to 45 feet in three seconds, sending all on board sprawling.

Not long afterward the E-7, commanded by Lt. Comdr. A. D. Cochrane, struck the net and was not so fortunate. Hopelessly snagged, it was unable to work itself free. At first the British submarine was spared from attack by surface craft because of extremely rough seas. Before long, though, the seas calmed and an explosive charge was lowered with its fuse activated. It exploded near the E-7. Another charge was about to be lowered when fuel oil began bubbling up. Surfacing through the bubbling oil came the E-7.

Immediately all of the Turkish ships' guns and shore batteries opened fire on the helpless submarine, which was quickly holed by several shots and began to sink. Through the open conning tower came the submarine's crew with their hands raised in surrender. Last out was Cochrane, who survived the war in a Turkish prison camp and later became a member of Parliament.

One effective antisubmarine scheme devised by the Royal Navy employed sailing ships working in conjunction with British submarines. A sailing ship would course through waters where it was thought U-boats might be patrolling. Beneath the sailing ship a British submarine would be submerged. Connecting the sailing ship on the surface with the submarine below would be a telephone line.

Normally a U-boat would not waste one of its limited supply of expensive torpedoes on a target as insignificant as a sailing ship. It would rather surface and sink it with a few less-precious shells from its deck gun.

As soon as the crew of the decoy sailing ship saw a U-boat surface, a telephone call would be made to the British submarine lurking below. More than willing to expend a torpedo to sink a U-boat, the British submarine would quickly maneuver into position and fire. Using this technique, the British submarine C-24 sank the U-40 on June 27, 1915. The U-23 was later sunk in the same way.

Out of this stratagem came one of the most effective — and the most heroic — antisubmarine measures of the war, the "mystery ship" or Q-boat. Q-boats were ordinary tramp steamers or other kinds of innocent-appearing ships which, under clever camouflage, carried 4.7-inch guns, torpedo tubes, and depth charge launchers. Great care was exercised in fitting out the Q-boats with armament so that there would be no way a U-boat captain, scrutinizing it through his periscope, could detect the fact that it was fully equipped to blow a surfaced submarine out of the water. Q-boats were manned by select crews of Royal Navy officers and sailors who, as part of the intended deception of U-boats, became to all outward appearances simply another ragtag merchant marine crew.

By day the Q-boat plied the sea lanes, with wash hanging out, its hull suitably streaked with rust, and its armament hidden under false deckhouses and crates. At night the darkened ship became a beehive of activity as its crew worked to change its identity. False funnels were erected or taken down, and different "house" colors were painted on them. A new name and home port were lettered on the Q-boat's stern, and false deck cargo might be constructed out of lumber and canvas.

With this done, the Q-boat would reverse its course and the next day would appear, to any submarine captain who might have observed it through his periscope the day before, to be a different ship with a different side of the Atlantic as its destination.

For long days, and sometimes weeks or months, a Q-boat might operate in the dangerous sea approaches to the British Isles without sight of a U-boat, for which all eyes on board were constantly straining. Then one day a periscope might be seen observing the ship. Perhaps, with luck, the submarine might be tempted to surface. At this point a portion of the Q-boat's crew would go into action, while the remainder would lie flat on the deck hidden beside the disguised armaments.

The first portion of the crew was known as the "panic party." Simulating the disorganized terror that often struck the civilian crews of merchant ships, the panic party would leave the Q-boat in wildly disorganized flight. Each of the party had a role to play: one was the "captain," another the ship's cook, and some Q-boats even had a downy-cheeked young sailor disguised in woman's clothes and playing the captain's "wife," following the custom of many merchant ships of the day which permitted the captain's wife to live aboard.

Over the side and into the boats the panic party would go. Some might "accidentally" fall overboard in the disordered rush. A lifeboat might, in apparent haste, be lowered improperly, tipping its panic-party passengers into the sea. Eventually all would be off the ship and pulling manfully at the oars. Each man was primed to give the same false information about the ship's name, cargo, and destination if the surfaced U-boat hailed them.

The purpose of the panic party's act was to make it appear that all of the crew had left, leaving an unmanned ship for the submarine to destroy at leisure.

All the while, though, hidden gun crews waited on the Q-boat beside their loaded guns. When the unsuspecting U-boat ventured within range, the white ensign of the Royal Navy would be run up to the gaff, the false sides would be dropped, and a hail of shellfire loosed from the Q-boat's guns. Sometimes, though, the gun crews had to endure heavy shell-fire from the U-boat before it ventured close enough to be within range of the Q-boat's guns.

At the height of their effectiveness there were as many as thirty Q-boats at sea at a time decoying submarines into position for attack, and the Germans soon grew wary of ships which might hide lethal armament behind apparently innocent exteriors. Martin Niemoller, a German submarine officer in World War I who later became an outspoken Protestant minister and was imprisoned during World War II for his criticisms of the Nazi regime, recalled his experience of being surprised by a Q-boat on the high seas.

After first damaging the ship, the SS Winona, with gunfire, Niemoller's submarine closed in on the surface for the kill. The Winona's crew had apparently fled the ship, but the U-boat men were leery.

"Suddenly," wrote Niemoller, "the steamer hoists a signal and at the same instant a salvo of three heavy shells screams overhead. The U-151's gun crew tumble down through the hatchway. The second salvo is short. The blowers have been stopped and the hissing of the automatic vents is heard while we flood.
"Crash! The third salvo strikes the boat, just as I am about to pull the hatch cover down. I fall down into the conning tower and close the armored deadlights over the scuttles. A big chunk of steel flies under the hatch cover and jams it open and we get a glimpse of flying fragments around our forward gun. Then the water closes over us while the boat shivers under the impact of a fourth salvo.
"We go down at a terrific rate. Sixty feet and a torrent of water pours into the boat through the jammed conning tower hatch. One hundred feet! Thank goodness the pressure of water forces the hatch cover home. One hundred thirty feet! One hundred sixty feet! We now pause."
"After a considerable period of time," writes Niemoller, "we gradually rise to periscope depth and the captain takes a look around. 'There's nothing more doing!' As I look through, our steamer, the decoy ship Winona, makes off in the distance towards the Irish coast. We let 'the beefs' imagine that they have really done in a German submarine and wait some time before surfacing."

Q-boats were not immune to being sunk themselves, even the best of them, one of which was the steamer Stonecrop. This rusty ship was on course from Gibraltar to England in September, 1917, when a lookout sighted what he reported as a lifeboat in the water. As the Stonecrop drew closer to it, the watching eyes of Royal Navy Commander Blackwood, captain of the ship, could see through his binoculars that the object was not a lifeboat, but the conning tower of a submarine just awash.

Day after day the Stonecrop had sailed the dangerous sea routes to and from the British Isles with all hands hoping to see just such a sight. Blackwood was determined that this submarine would not escape the guns carefully camouflaged behind the sides of false crates and deck houses. He would have been doubly determined to sink it if he had known that the submarine was a brand-new and large one, the U-88, and that its captain was Comdr. Walther von Schwieger who, as captain of the U-20, had sunk the liner Lusitania.

From a distance the U-88 began firing its deck gun at the Stonecrop. The Q-boat replied inaccurately with its own stern gun. (The men manning the small, exposed stern guns on Q-boats were perhaps the only gun crews in the war who had orders not to come too close to their targets so that they wouldn't scare a surfaced U-boat into submerging.)

The U-boat's gun found the Stonecrop's range, and shells began exploding on the steamer's deck and superstructure. Now came the most trying part of the Q-boat's act. It had to take punishment without dishing it out, biding its time until it had the best possible target. Commander Blackwood started up his "smoke and fire"" apparatus to create the impression of fire out of control on board. The Q-boat's panic party, complete with spurious captain, manned the lifeboats in chaotic haste and pulled away from their blazing ship.

At this point the suspicious U-88 submerged at a distance of three miles, and it appeared that the submarine had chosen to leave the blazing and damaged ship alone. In a few minutes, though, the U-boat's periscope appeared a mile off the Stonecrop's port beam where it was sighted by Blackwood and his men as they peered through tiny slits in the false siding that hid their guns. The periscope came closer and passed completely around the ship, examining it at a distance of only 300 yards. Von Schwieger was a wily and experienced captain, and insofar as possible he wanted to make sure that his prey was not going to strike back.

Blackwood and his men had done their job of camouflaging well, and after careful scrutiny von Schwieger decided that the ship was exactly what it seemed to be — a tramp steamer and nothing more. At 600 yards from the Stonecrop the bow and conning tower of the U-88 broke the surface, and soon the submarine's deck was clear of the water. Its conning tower hatch opened and out ran the German gun crew to their stations. Von Schwieger was confident that they would put a quick end to their target.

On the Stonecrop Blackwood's heart was pounding in his chest. This was the moment he had been waiting for through all the merciless shelling by the U-88. His hand-picked gun crews lay flat on the deck.

"Stand by!" Blackwood ordered. "Let go!"

With a rattle of chains the false sidings fell quickly away, revealing the round muzzles of the Stonecrop's guns. Almost in the same instant the first rounds were fired.

On the U-88 the crew of the deck gun ran to get back into the submarine before it crash-dived beneath the surface. Von Schwieger, perhaps cursing himself for his mistake, locked the conning tower hatch behind them. The next minute would tell the tale — for it would take that long for the U-88's ballast tanks to fill with water and take the U-boat down to safety.

Aboard the Stonecrop Blackwood watched his first shell miss its mark. The second went wild also, and the third. The fourth hit the base of the conning tower, and the fifth smashed into the hull beneath the deck gun at the waterline. The sixth hit the hull between the gun and the conning tower. The seventh hit the stern and loosed clouds of water vapor from the submarine's hull — this was the compressed air with which von Schwieger would blow the U-88's ballast tanks empty of water in order to surface. Before the U-boat slipped from view five more hits were scored. It sank with all hands, including its Commander, von Schwieger.

With the action victoriously completed, Blackwood called back the boats with the Stonecrop's panic party, who had wildly cheered the hits scored by their shipmates. The fires on board the Q-boat were extinguished, and it headed for port for repairs, but it was destined never to arrive. The next day an unexpected torpedo struck the Stonecrop, and this time all hands — not just the panic party — took to the lifeboats. When the ship had sunk, the attacking U-boat surfaced and cruised slowly up to the boats.

"What ship, what cargo, and where bound?" called the German captain in accented English. Commander Blackwood maintained the Q-boat's ruse to the end and answered with false information. He and his men were afloat on the cold and stormy sea for six days before help came, and in that time an officer and twelve men died of exposure.

Submarines themselves, both Allied and German, accounted for many submarines on the opposing side during the war, and hard-bitten submariners liked nothing better than to get a shot at an enemy submarine. The German UB-15 alone accounted for four: the British E-22, sunk on April 25, 1916, in the North Sea; the C-34, sunk off the Shetland Islands in July, 1917; the D-6, torpedoed off the coast of Ireland in June, 1918; and the E-20.

The loss of the E-20 to a torpedo of the UB-15 was particularly bitter. It happened in a strange way. The E-20 was one of the flotilla of British submarines operating in Turkish waters. Also operating there was another Allied submarine, the Turquoise, of the French Navy.

Secret plans were made for the E-20 to rendezvous with the Turquoise in the Sea of Marmara to exchange information. En route to the rendezvous the Turquoise became ensnared in the Dardanelles antisubmarine net and surrendered. In the chaos of the event the French submarine captain forgot to destroy his secret papers, which fell into enemy hands.

The captured Turquoise could not keep its rendezvous with the British E-20 but the German submarine UB-15 (Lt. Comdr. Heino von Heimburg commanding), acting on information about the rendezvous taken from the French submarine, could take its place. When the unsuspecting E-20 approached the planned rendezvous point it had no idea that the waiting submarine was not the Turquoise until a torpedo from the UB-15 struck and sank it. Nine men in the E-20's conning tower, including the captain, survived the explosion and were rescued by the U-boat.

A fantastic stroke of bad luck deprived Lt. A. C. Bennett, commanding officer of the United States submarine L-11, of a U-boat kill after the United States entered the war. Bennett found a U-boat on the surface some nine hundred yards away, oblivious to the L-11's periscope. Bennett quickly made his calculations and fired a torpedo. Five seconds later he fired a second. The torpedoes ran "hot, straight, and normal," as American submariners say of a properly functioning shot, but when they were only two hundred yards from the U-boat there was a tremendous explosion. Apparently the second torpedo was running slightly faster than the first and — one chance in a million — caught up and ran into it, exploding both. Neither torpedo reached its target, and the U-boat promptly submerged, unharmed.

Commander H. Hoppe, who with his submarine the U-22 was later sunk by a Q-boat, set sail on patrol from Wilhelms-haven, and had the good fortune of finding a submarine in his sights. A torpedo sent the submarine to the bottom, with only a single survivor left, dazed but swimming.

Hoppe surfaced and took the survivor aboard, where it was immediately realized with horror that he was wearing a German uniform. When the survivor had recovered enough to speak he confirmed that the sunken submarine was the U-7, commanded by Hoppe's lifelong friend, George Koenig. Doubtless the more superstitious of the U-22' crewmen wondered if the disaster was not in some way related to the fact that the day on which their ill-fated patrol had begun in Wilhelmshaven in January, 1915, was Friday the thirteenth.

Another submarine that left Wilhelmshaven on that same Friday the thirteenth was the U-31, Lieutenant Commander Wachendorff in command. It failed to return from the patrol and was declared lost. But the story did not end there. Six months later the U-31 surfaced near the coast of England, dead and derelict.

The U-boat washed aground on the English shore, and an armed group of Royal Navy men carefully opened its conning tower hatch and made their way down into the submarine behind leveled guns. There was no need for the precaution. Every man on the U-31 was in his bunk — and dead.

The most likely explanation was this. The U-31, after leaving Wilhelmshaven, made its way to its operating area near the British coast and settled to the bottom to await daylight, when it would begin searching for targets. With all asleep in their hammocks and bunks, noxious gas escaped undetected into the living areas, suffocating every man where he slept. For six months the U-31 lay submerged with all on board dead, but in this time the submarine's compressed air began to escape, gradually forcing the water out of its ballast tanks.

In six months enough compressed air had escaped to float the U-31 to the surface, a phantom "Flying Dutchman" of World War I — and more fuel for seamen's superstitions about sailing on Friday the thirteenth.

In addition to all the intentional means of sinking submarines, there were more than a few unexpected and unintentional means of sinking them as well. Accidents continued to take a toll, and probably the worst of these in the war involved three new British submarines training in the Firth of Forth. One of the new boats collided with another and both went down with all hands. A destroyer sped to the scene to search for survivors. In the process it rammed the third submarine, sending it to the bottom too. There were no survivors from any of the three.

Another freak accident almost sank the U-139 and Comdr. Lothar von Arnauld de la Periere who, in spite of his French surname, was the top-scoring submarine commander of the entire German submarine force.

Von Arnauld torpedoed a ship at close quarters. The momentum of the stricken ship carried it over the U-139, and it sank on top of the U-boat before von Arnauld could steer clear. The sinking hulk tore away the U-139's periscope, blinding it, but the submarine itself worked free before being pushed to the bottom.

In a similar instance a British submarine rammed a U-boat, tearing a hole in the German's hull. In the process the British submarine slid on top of the German submarine's deck. The U-boat, apparently fighting an inrush of water through the hole in its hull, blew all of its tanks in an effort to come up to the surface. The British submarine was raised twelve feet before its captain realized what the U-boat was trying to do. As soon as he did realize, he ordered all of his tanks flooded to counter the German effort to surface.

In a strange eyeball-to-eyeball confrontation during this unusual struggle, the German and the British captains stared at each other through their periscopes. The German boat, unable to surface with the British submarine on its back, and unable to stem the flood of water pouring into its torn hull, sank with all hands, its periscope silently slipping beneath the waves out of the British captain's view.