Once a well-kept secret, radar’s role in the Allied victory is now being told by the scientists who developed it.

By Jon Guttman

Nobody can deny that radio detection and ranging–radar–was one of the most significant technological innovations of World War II. Without the advance knowledge, acquired by means of its coastal network of radar sites, of where the Luftwaffe would strike in the summer of 1940, the Royal Air Force would not have been able to make the most effective use of its limited aerial resources and the Battle of Britain might have had a different outcome. In the years that followed, radar played an increasing role in navigation, the detection of ships and even submarines at sea, the accurate pinpointing of bombs at night and in foul weather, and numerous other purposes. So critical was radar’s use as a weapon that for much of the conflict a virtual electronic war was pursued by the British and Germans, each seeking to develop not only better radar but also a means of countering the other side’s radar.

Three recent additions to the World War II historian’s library address wartime development and use of radar from three different angles. The most wide-ranging of the trio is Pioneers of Radar, by Colin Latham and Anne Stobbs (Sutton Publishing Ltd., Phoenix Mill, Thrupp, Stroud, Gloucestershire, England, 1999, $36.95), an overview of the multiple contributions made by Britain’s then top-secret Telecommunications Research Establishment, or TRE, as told by the men and women who worked in that organization.

Britain’s advances in radar development seem the more remarkable when one realizes that German scientists had demonstrated its principles before Sir Henry Tizard formed his committee, and Robert A. Watson-Watt and Arnold F. Wilkins worked out the basic principles of British radar early in 1935. On August 3, 1938, General Wolfgang Martini, the Luftwaffe’s chief signals officer, dispatched the airship LZ-130 Graf Zeppelin on a spy mission to observe and monitor the installations being built along Britain’s coast, but due to several factors, her technical team failed to detect any radar signals. “Perhaps the failure of the Zeppelin mission was the first lost nail that cost Germany a battle and a war,” opined former technical officer Sir Edward Fennessy after learning of it from Martini in the early 1950s. A more significant reason for the British lead, according to Denis Bolesworth, a former de Havilland Mosquito navigator and bombardier in No. 105 Squadron (a Pathfinder unit that employed radar to pinpoint targets for Bomber Command) was that “there was a marked difference between the structure of the Signals Group in Germany and TRE, as theirs was directly under Göring and what he said or thought went.” While the TRE’s departments cooperated constantly, with one department’s problem often being solved by a scientist in another, Martini was always answerable to Reichsmarschall Hermann Göring, who dismissed radar’s importance in 1940 and for too many years thereafter.

The story of radar’s development has been told before, but there are fresh insights–and a variety of amusing anecdotes–to be derived from reading about it firsthand from the people who developed it and who, for many years, had to keep silent about their contribution to victory.

One major derivation of TRE’s research was Oboe, a ground-controlled blind-bombing system that eventually transformed Britain’s night-bombing campaign over Germany from a haphazard, costly fiasco to a devastatingly effective instrument of victory. Beam Bombers: The Secret War of No. 109 Squadron, by Michael Cumming (Sutton Publishing Ltd., Phoenix Mill, Thrupp, Stroud, Gloucestershire, England, 1998, $36.95), presents a comprehensive, detailed history of the first RAF Pathfinder squadron to employ Oboe in action, combining the device’s technical development with its actual use by Mosquito crews that flew ahead of the bombers. It took airmen of a special sort to fly such missions, armed only with a device that had barely been proved and which was perfected as they went along–provided they survived to report the results. By the end of the war, they and their colleagues in No. 105 Squadron had successfully bombed or marked their targets by means of Oboe 5,908 times out of 9,624 sorties–a success rate of just over 61 percent. One of the squadron’s navigators, Charles Harrold, later witnessed with considerable wonder the accuracy of laser-guided bombs during the Gulf War of 1991, but added, “What our Mosquito crews were able to achieve half a century earlier was to my mind equally remarkable, given the extent of comparative know-how.”

Another important radar-derived weapon is described in They Never Knew What Hit Them: The Story of World War II’s Best Kept Secret, by Ralph B. Baldwin (Reynier Press, Naples, Fla., 1999, $39.95). The “secret” was the radio proximity fuze, for security reasons more widely known as the VT or “variable time” fuze. A dedicated team of American scientists, including Baldwin, combined within a 90mm anti-aircraft or a 155mm artillery shell the electronics, explosives and protection necessary to create, as Baldwin puts it, “the world’s first ‘smart’ weapon.”

At a time when anti-aircraft fire relied on timed fuzes, volume of fire, altitude and speed calculations and sheer luck to explode near their targets–with disproportionately scant results–the VT fuze exploded when it came within 75 feet of an airplane or other targets that reflected radio waves. The device was first used by U.S. Navy ships in hopes that unexploded shells would fall into the sea rather than into enemy hands. During a Japanese air attack off Munda on January 5, 1943, the light cruiser Helena used one to destroy an Aichi D3A1 dive bomber. Proximity fuzes became more prolific thereafter, priming both anti-aircraft and anti-personnel shells from the Allied invasion of Sicily in July 1943 to the end of the war. The fuzes’ importance became particularly critical in countering German guided bombs, such as the V-1, and Japanese suicide planes, and it is reasonable to suggest that the invention of the VT fuze shortened the war by a year and saved countless Allied lives.

The special problems that were solved in the process of developing the VT fuze represent an achievement that deserves to be explained, and as a participant Baldwin is both qualified and able to preserve the story in commendable detail. On the other hand, Baldwin’s narrative is not as easy a read as the reminiscences of his British colleagues in Pioneers of Radar. He is sometimes prone to ramble and repeat what he regards as key points, and the book suffers from somewhat amateurish editing and layout. Even with these faults, however, They Never Knew What Hit Them is an important document, not only for giving overdue attention to a vital but overlooked weapon but also as a reflection of the minds that produced it.