Exclusive First Read: Erik Larson's 'Dead Wake'

The luxury liner Lusitania departed New York City en route for Liverpool on May 1, 1915. World War I was raging in Europe, but the passengers on the world's fastest liner were sure they were in no danger — despite a warning from the German Embassy in Washington that "travellers sailing in the war zone on the ships of Great Britain or her allies do so at their own risk." Even the Lusitania's captain, William Turner, said his vessel was too fast for submarines to pose a threat.

But at that very moment, the German sub designated U-20 was heading towards the Irish Sea, on a collision course with the Lusitania. The subsequent tragedy — one torpedo, and the great ship sank in just 18 minutes, taking more than a thousand lives with it — was a turning point that helped bring the hesitant United States closer to entering the war. Erik Larson's new Dead Wake is a tense and thrilling account of the deadly journey, switching back and forth between the Lusitania and the surprisingly human captain of the U-20, Walther Schwieger. In this excerpt, we meet Schwieger, cruising along the Ems river on his way to the ocean, and get a glimpse into the life of a U-boat captain. Dead Wake will be published March 10.

THE HAPPIEST U-BOAT

That same day, Friday, April 30, a vessel of a dif­ferent sort began making its way toward the British Isles, the German submarine Unterseeboot-20, traveling under orders that gave its new patrol a heightened urgency. The boat slipped from its harbor at Emden, on the northwest coast of Germany, at 6:00 a.m., with no fanfare. The crews of U‑boats nicknamed the North Sea "Bright Hans," but today the sea and sky were gray, as was the flat terrain that surrounded the harbor. Submarines stood side by side at their moorage, roped to one another, their conning towers like distant castles. The wind came onshore at 4 knots.

U‑20 moved seaward along the Ems River, in silence, and left almost no wake. Atop its conning tower stood Kptlt. Walther Schwieger, the boat's captain, in his peaked cap and waterproof leathers. The tower was a squat chamber jutting up from the boat's midsection that housed an array of controls and two periscopes, one his primary battle periscope, the other an auxiliary. During underwater attacks, Schwieger would station himself here within the tower's thick carbon-steel walls and use the main periscope to direct his crew in launching torpedoes. When surfaced, the small deck on top of the tower gave him a promontory from which to scan the seascape around him but provided little shelter from the weather. The morning was cold; the scent of coffee rose through the hatch below.

Schwieger guided the submarine along the river and on into the shallows outside the harbor. The boat moved due west and by about 9:30 a.m. passed the lighthouse and wireless station on Bor­kum, a small barrier island that served as an important landmark for departing and returning submarines.

Schwieger had just turned thirty-two years old but already was considered one of the German navy's most knowledgeable com­manders, so much so that he was consulted on submarine matters by his superiors, and his boat was used to try out new submarine tactics. He was one of the few captains who had been in the sub­marine service before the war began. He was tall and slender, with broad shoulders. "A particularly fine-looking fellow," one of his crew members said. His eyes were pale blue and conveyed coolness and good humor.

Around noon, Schwieger's boat entered the deep waters beyond Borkum, in a portion of the North Sea known variously as the German Bight or Heligoland Bight. Here the sea bottom fell away and on bright days the water turned a deep cobalt. In his War Log, kept for every patrol, Schwieger noted that the sea was running a three-foot swell from the west and that visibility was good.

Although he was free to submerge the vessel if he wished, he kept it on the surface, where he could travel farther and faster. His twin diesel engines could generate up to 15 knots, enough to over­take most conventional merchant ships. At routine cruising speeds, say 8 knots, he could travel up to 5,200 nautical miles. Once sub­merged, however, Schwieger had to switch to two battery-powered engines, lest the diesels consume all the oxygen in the boat. These engines could deliver 9 knots at best, and only for a brief period. Even at half that pace, a submerged U‑boat could travel only about 80 nautical miles. These speeds were so slow that sometimes U‑boats trying to make their way against the fast currents of the Strait of Dover, between England and France, were unable to ad­vance. U‑boats in fact traveled underwater as little as possible, typ­ically only in extreme weather or when attacking ships or dodging destroyers.

For much of his first day at sea, Schwieger was able to maintain wireless contact with the station on Borkum Island and with a naval vessel in Emden Harbor, the Ancona, which was equipped with wireless apparatus that could communicate over long distances. Schwieger noted in his log that his ability to trade messages with the Borkum transmitter ceased when his U-boat was 45 sea miles out but that he maintained a good connection with the Ancona. Along the way his wireless operator repeatedly sent test signals, something U-boat wireless operators often did, as if to postpone the inevitable moment when the boat would be out of range of all friendly sources and utterly on its own.

This isolation made the U-boat distinct among Germany's naval forces. Surface ships usually traveled in groups and, given the height of their masts, could stay in contact with their bases; U-boats traveled solo and lost contact sooner, typically after sailing only a couple of hundred miles. Once at sea, a U-boat captain was free to conduct his patrol in whatever manner suited him, without supervision from above. He alone determined when and whether to attack, when to ascend or dive, and when to return to base. He had absolute control over the boat's periscope. "I want to stress that the submarine is only a one-eyed vessel," said a U-boat commander, Baron Edgar von Spiegel von und zu Peckelsheim, who knew Schwieger well. "That means, only the one who is at the periscope with one eye has the whole responsibility for attacking or the safety of his ship and crew."

The view it provided was a crabbed one at best. A captain got only a brief, platelike glimpse at the world around him, during which he had to make decisions about a ship's nature, its nationality, whether it was armed or not, and whether the markings it bore were legitimate or fake. And if he decided to attack, it was he alone who bore the responsibility, like pulling the trigger on a gun, but without having to see or listen to the result. All he heard was the sound of the exploding torpedo as transmitted through the sea. If he chose to watch the tragedy unfold, he saw only a silent world of fire and terror. Once, Spiegel attacked a transport carrying horses and watched one of the animals — "a splendid, dapple-gray horse with a long tail" — leap from the ship into an overloaded lifeboat. After that, he wrote, "I could not endure the spectacle any longer." He pulled down his periscope and ordered his boat into a deep dive.

"It was a very hard task and entirely different from the fighting in the army," said Spiegel. "If you were bombarded by artillery and you had orders to leave your trenches and attack you were in full excitement personally. In the submarine perhaps you were sit­ting in your small cabin drinking your morning coffee and [eating] ham and eggs when the whistle or the phone rang and told you, 'ship in sight.'" The captain gave the order to fire. "And the results of these damn torpedoes were certainly very often heartbreaking." One ship, struck in the bow, sank "like an airplane," he said. "In two minutes the 10,000 ton ship disappeared from the surface."

Such authority could be thrilling but carried with it a certain loneliness, amplified by the fact that Germany had very few subma­rines at sea at any one time. As of May 1915, Schwieger's U‑boat was one of only twenty-five in Germany's fleet that were capable of traveling long distances. Only seven were in service at a time, owing to the fact that after each cruise the boats often needed sev­eral weeks for repair and overhaul. When on patrol, Schwieger's U‑boat occupied a pinpoint in a vast sea.

On this cruise, Schwieger carried with him a set of orders that had been delivered to him by hand. These were the result of a newly risen fear that Britain was about to launch an invasion of Germany itself, from the North Sea at Schleswig-Holstein, and that the ships carrying the invading troops would depart from ports different from those customarily used to resupply British forces in France. Intelligence reports had long suggested such an invasion might be in the works, but German naval officials were at first skeptical. Now, however, they had come to believe the reports might be true. Schwieger's orders directed him to hunt and attack these trans­ports in a designated square of sea off Liverpool, between England and Ireland, and to sail there "on the fastest possible route around Scotland." Once there, the orders said, he was to hold that position "as long as supplies permit."

The mission must have been urgent indeed to cause the navy to override the maritime superstition about Friday departures.

Reprinted from Dead Wake: The Last Crossing of the Lusitania. Copyright 2015 by Erik Larson. With permission from Crown Publishers, an imprint of Penguin Random House LLC.

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