How Scientists Sank the U-Boat

Allied scientists during World War II produced radar and other breakthroughs still in use today. Marc Levinson reviews Stephen Budiansky's "Blackett's War."

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·        By MARC LEVINSON

Patton. Yamamoto. Montgomery. Zhukov. Rommel. Nimitz. Seven decades later, the names of the men who commanded the armies and navies in the great battles of World War II are still familiar. But as Stephen Budiansky shows persuasively in "Blackett's War," the outcome of the war hung on the work of a far more obscure group of fighters: the physicists, biologists and mathematicians who applied scientific thinking to battlefield problems. By teaching Allied military leaders to use their resources effectively and asking hard questions to challenge established wisdom, the scientists revolutionized warfare and contributed mightily to Germany's defeat. In the process, they created a new discipline, operations research, which plays a vital role in business to this day.

The real hero of this story is Winston Churchill, who in the mid-1930s was a powerless backbencher of Parliament. Churchill, who had been in charge of the British Navy in the early part of World War I and later minister of munitions, was thoroughly skeptical of military ways. At a tennis tournament, he made the acquaintance of the Oxford University physicist F.A. Lindemann, who had performed experiments aboard aircraft during the war. He lectured Churchill on ways science might help protect Britain against aerial bombardment.

Churchill, always an enthusiast for scientific ideas, pressed the government to bring in scientific advisers on military affairs as early as 1934. So it was that chemist Henry Tizard, biologist A.V. Hill and physicist Patrick Blackett entered the British defense establishment. Hundreds more scientists came after, much to the discomfort of many hidebound officers. The scientist's job, Blackett would say after the war, "is to improve matters if he can, and if he cannot, to say nothing."

In 1935, a group of these experts began exploring how an aircraft in flight would distort radio signals. The fruit of their efforts became known as radar—a system that could bounce radio waves off airplanes and determine the planes' location from the echo—and England's south coast was lined with tracking stations by the time Great Britain and Germany went to war in September 1939. The scientists were less well received at the admiralty, whose inbred conservatism made it uninterested in radar—an attitude that would deprive the British navy of a potential early advantage against the German fleet.

Yet the scientists were meant not so much to invent new devices as to improve the way war was waged. This was a tough assignment, for it involved telling generals and admirals how to do their jobs. To embed themselves in military units to study real operational problems, they needed strong support from Churchill, who became prime minster in May 1940. But Churchill's excitement could get the better of him. Again and again, egged on by Lindemann, he insisted that the scientists pursue revolutionary ideas that never seemed to pan out. The search for aerial mines that could intercept bombers and a device to create an updraft that would flip an attacking airplane upside-down got in the way of fighting the real war.

Mr. Budiansky suggests that the scientists' greatest contribution to the war effort was forcing the military to make decisions based on data instead of prejudice. Nowhere was this more important than in the North Atlantic, where German Unterseeboote—U-boats—had waged a devastating war on merchant shipping. U-boats often operated on the surface, and were frequently spotted at close range by Royal Navy ships escorting convoys. The escorts were trained to drop depth charges 250 feet apart and set to explode 100 to 150 feet underwater and were having negligible success against the subs.

Blackett, then working for the Navy's Coastal Command, asked a physicist named E.J. Williams to take on the issue. Williams showed mathematically why an escort ship following the Navy's instructions was unlikely ever to hit a U-boat. He recommended that the defenders ignore any U-boat that had been beneath the waves for more than 15 seconds. But U-boats that had just dived were to be attacked immediately with closely spaced depth charges set to explode at only 25 feet. The kill rate rose by a factor of 10.

One of Blackett's own insights seems shockingly simple in retrospect. The Coastal Command tracked the estimated location of every U-boat believed to be in the Atlantic and used a fleet of patrol planes to search for them. Knowing that U-boats usually traveled on the surface, Blackett calculated the number of sightings the planes should report. The actual number was far lower, posing the question of why the planes were performing so poorly.

The obvious answer was that U-boats were spotting the planes and diving before being seen. With that answer in hand, Blackett began searching for explanations. "What color are Coastal aircraft?" an air force officer asked him. They were black: the planes had been shifted from night bomber duty to ocean patrol. Painting the undersides of the wings reflective white made the planes harder to see, and the rate of U-boat sightings doubled.

Some of the exploits the author recounts are well known, notably the cracking of German naval codes after British scientists reverse-engineered the Enigma coding machine. Others, such as changes in the way British aircraft hunted U-boats in the Bay of Biscay and detection of the Germans' method of using radio beams to help Luftwaffe bombers reach their targets, are less famous. The book's title is a bit misleading—the book isn't a biography of Blackett, nor was he solely responsible for bringing science into war—but Mr. Budiansky's research seems thorough and focused, and his lively writing style delivers a fascinating portrayal of how science contributed to winning the war in Europe.

Perhaps even more important for business readers, Mr. Budiansky helps us understand the creation of operations research as a scientific enterprise. Executives had been trying to apply statistical analysis to business since the rise of scientific management in the early years of the 20th century. But scientific management was remarkably unsophisticated, useful for little beyond time-motion studies that revealed how many pounds of coal a worker should shovel each hour.

Blackett and his fellow British scientists, and, from 1940, their American counterparts under the leadership of Vannevar Bush and the National Defense Research Committee, showed how careful quantitative analysis could provide far better guidance for decision makers than tradition. Concepts such as probability and optimization, honed in studies analyzing the placement of antiaircraft batteries and the flight patterns of planes on patrol at sea, made their way into the language of business. If your trucking company is trying to figure out how to design a terminal to ensure the smoothest flow of vehicles and goods, or if your hospital is seeking ways to reduce wait times in the emergency room, you are building on a foundation laid during the war.

After the war, Blackett and some of his colleagues, mainly on the political left, sought to transfer their expertise from military concerns to social policy. Their effort was largely a failure. As Mr. Budiansky points out, operational research had flourished in wartime "within a framework where what constituted success—U-boats sunk, merchant ships saved—was usually clearly understood and widely agreed." When it came to promoting exports or improving public health, by contrast, the determination of which policies were optimal was a matter more of political viewpoints than of mathematical modeling. Rational, dispassionate analysis has limitations.

—Mr. Levinson's books include
"The Box: How the Shipping Container Made the World Smaller and the World Economy Bigger."

A version of this article appeared February 16, 2013, on page C7 in the U.S. edition of The Wall Street Journal, with the headline: How Scientists Sank the U-Boat.