Seven torpedoes, five ships sunk, and a sixth damaged—all in a single salvo. It was a World War II record, and the man who set it, only minutes later, sat calmly on his sinking submarine, smoking a cigarette. Otto Kretschmer, the most successful U-Boat ace, was ending his wartime career in a way no one expected. He didn’t die heroically in battle, but instead made a mistake that cost him six years of freedom.
A Gentleman in a German Uniform
Otto Kretschmer was born in 1912 in Silesia, into a teacher’s family, far from the political upheavals of the Weimar Republic. His teachers quickly noticed something special in him; a school report once highlighted his „remarkable courage” and his dream of a naval officer’s career. He graduated high school at age seventeen, which posed a problem because he was too young for military service.
His father sent him to England, where young Kretschmer studied at the University of Exeter under the guidance of a naturalized German. It’s rarely mentioned, but the future scourge of the British merchant fleet first learned to respect the British and their practical approach to education.
This experience shaped his later attitude toward the enemy. He treated the English with a certain respect, believing rumors about their technological inventions.
A tragic event forced Kretschmer’s return to Germany. His mother died of tetanus due to medical errors, definitively ending his English adventure. Instead of returning to studies, he traveled through France, Switzerland, and Italy, ultimately joining the Kriegsmarine. No one then suspected that this quiet young man would become the deadliest submarine commander in history.
Master of Stealth and Precision
Kretschmer developed his own tactics, which yielded staggering results. Instead of long-range attacks, he would break into convoys and fire at close range, minimizing the chances of missing.
Unlike other commanders, he avoided spectacular but risky surface attacks. His method worked flawlessly for sixteen patrols on the U-23 and U-99.
The numbers speak for themselves: forty-seven Allied merchant ships with a total tonnage exceeding 274,000 tons, plus the British destroyer HMS Daring sunk in February 1940. Remarkably, Kretschmer achieved these results in just 213 days spent at sea. He was a sinking machine, operating with cold precision and without unnecessary risks.
His fame rose rapidly, making him one of the most recognizable U-Boat officers alongside Joachim Schepke. Both commanders were friends and rivals, competing for the title of the most successful U-Boat ace. No one anticipated that fate would reunite them that same night—this time in tragic circumstances.
The Night That Changed Everything
On March 16, 1941, Kretschmer and Schepke attacked convoy HX-112, expecting another easy victory. Kretschmer was in top form—seven out of eight torpedoes hit their marks, sinking five ships and damaging a sixth. It was the most devastating single salvo of the entire submarine war. Using the smoke from burning tankers, U-99 tried to make its escape.
And then the ace made the mistake that cost him everything. Kretschmer mistakenly believed he had been detected and ordered an emergency dive. In reality, no one had picked up his position—only his maneuver gave his location away to the destroyer Walker’s sonar. Depth charges damaged the depth gauge, U-99 started an uncontrollable dive, and panic forced the commander to blow the ballast tanks and surface right in front of enemy ships’ guns.
Kretschmer kept his composure even in the face of defeat. He sat on the sinking submarine and lit a cigarette as his crew gathered behind him „like ducklings behind their mother.” He managed to send a final, unencrypted message to Admiral Dönitz: „Two destroyers. Depth charges. 53,000 tons. Captured, Kretschmer.” Then he asked the British captain to save his crew—and most of them really did survive. That same night, Schepke was killed on U-100. Germany lost two aces in less than an hour.
A Prisoner Who Never Gave Up
Kretschmer was sent to a POW camp, first in Scotland, then in Canada, where he quickly became senior prisoner in the camp. However, contrary to expectations, he didn’t simply wait out the war. He established a covert intelligence network, codenamed „Lorient,” which provided Admiral Dönitz with vital information, including who sank U-99, POW camp plans, and military news.
From autumn 1942, Kretschmer and three other U-Boat commanders were planning a spectacular escape. Submarine U-536 was supposed to pick up the escapees off the Canadian coast. The plan was bold and well-prepared, but shortly before it was to be executed the British discovered it. Kretschmer was arrested, and Operation „Kiebitz” ended in failure.
The most effective U-Boat ace spent six years in captivity and was among the last Kriegsmarine officers to be released. His story is a paradox of submarine warfare: the man who sank more ships than anyone else survived the conflict precisely because he made a mistake and was captured. Had he not given that unnecessary dive order, he likely would have died like so many other U-Boat commanders. Sometimes, failure saves your life.
Autor
Margot Cleverly
Margot's journey into women's history began with a box of forgotten letters in a Cambridge archive – suffragettes whose voices had been silenced for over a century. Since then, she's been on a mission to uncover the stories history overlooked.
What she writes about: Queens who ruled from the shadows. Scientists whose male colleagues took credit. Revolutionaries who risked everything. But also ordinary women – those who survived wars, raised families through upheaval, and shaped their communities in ways no one bothered to record.
Margot turns historical figures into real people. She writes with warmth and detail, making centuries-old stories feel surprisingly relevant. Rigorous research meets accessible storytelling – no dusty academic jargon, just compelling narratives backed by solid facts.
When she's not writing, you'll find her in regional archives, collecting oral histories, or visiting sites connected to the women she writes about.