It’s often said that wars bring about a wave of innovation — necessity being the mother of invention, as the old adage goes. In reality, that’s not necessarily true. According to some studies, there tends to be a significant decline in inventiveness immediately after the outbreak of a war, followed by a marked surge, the net result being a fairly standard rate of innovation overall. Creation through necessity or even desperation certainly happens, but prosperous, peaceful, and free societies tend to be just as inventive, if not more so.
That said, plenty of technological innovation took place during World War II, especially in fields that had military applications. Here are some of the most pivotal, successful, and enduring inventions to come out of the war, from handy tools used by millions of people to miracle drugs that have saved countless lives.
In 1943, Vesta Stoudt, an Illinois woman with two sons serving in the U.S. Navy, was working in an ordnance plant when she noticed a problem with the ammunition boxes she was packing. The boxes were sealed with paper tape with a tab to open them, but this tab could easily tear off, leaving soldiers potentially scrambling to open the boxes in life-threatening situations. So, Stoudt came up with the idea of a waterproof fabric tape with which to seal the boxes — an idea she sent to none other than President Franklin D. Roosevelt. Impressed, the President sent her letter to the War Production Board, which soon came up with what we now know as duct tape. Not only was it easy to apply and remove on ammo boxes, but it also turned out to be endlessly handy for quickly repairing military equipment, including vehicles and weapons.
The fundamental principle underlying modern radar (which is actually an acronym for “radio detection and ranging”) was first observed in 1886 by physicist Heinrich Hertz, who found that electromagnetic waves could be reflected from various objects. It was during World War II, however, that modern, practical radar was developed. Britain had already established a chain of radar stations along its south and east coasts by the outbreak of the war, allowing for the detection of enemy aircraft at a range of 80 miles. The British then invented the cavity magnetron in 1940, paving the way for far more compact, powerful, and sensitive radar units (and, as it happens, microwave ovens).
British engineer and RAF officer Frank Whittlefirst put forward his vision of jet propulsion in 1928, at which time he was roundly ridiculed. Undeterred, he did a successful test run of the first practical jet engine in 1937, albeit on the ground. Then, in August 1939 — a month before the outbreak of the war — the German-built Heinkel He 178 made the first jet-powered flight in history. The war ramped up the development of jet engines, and Whittle found himself with more funding than ever before. In May 1941, his jet-propelled Gloster E.28/39 took flight, achieving a top speed of 370 mph at 25,000 feet, faster than any other conventional propeller-driven aircraft. Though neither the Heinkel He 178 nor the Gloster E.28/39 ever flew combat missions during the war, the “jet age” had begun. The first jet aircraft used in the war were the Messerschmitt Me 262 and Gloster Meteor, starting in 1944.
During World War II, Harry Coover was part of a team at Eastman Kodak trying to find a way to make clear plastic gun sights for Allied soldiers. During his research, Coover accidentally created a new compound called cyanoacrylate. At the time, he and his team found the new compound to be incredibly durable but way too sticky to use, and they soon abandoned the substance. Nine years later, in 1951, Coover returned to cyanoacrylates, and this time he and his team recognized new potential in them. The sticky adhesive required no heat or pressure to bond, and the bond was incredibly strong. Coover had invented super glue, albeit by accident.
It’s hard to say precisely when the first computer was invented. You could argue that it was the abacus of the ancient world, and there’s certainly a case to be made for Charles Babbage and his mechanical computer of the early 19th century. But when it comes to programmable, electronic computers, we can reliably trace the origin to the Second World War. First there was Colossus, a huge set of computers developed by British code breakers at Bletchley Park between 1943 and 1945. In its first test, Colossus successfully decoded a genuine coded message so quickly that 10 improved machines were ordered right away. Then there was ENIAC (Electronic Numerical Integrator and Computer), developed by the United States and completed in 1945, which lays claim to being the first programmable, general-purpose, electronic digital computer. (It was designed specifically for computing values for artillery range tables, but had other uses as well.) Together, they marked a turning point in the history of modern computers.
Not all the inventions that arose from World War II had military applications. In 1943, Richard James, a naval mechanical engineer stationed at the William Cramp & Sons shipyards in Philadelphia, was working to devise springs that could keep sensitive ship equipment steady at sea. While he was working, he accidentally knocked a coiled spring from a shelf. He watched, surprised and amused, as the spring seemingly walked its way end-over-end across the ground. That same day, he went home and told his wife, Betty James, about an idea he had for a new toy. They took out a $500 loan, co-founded James Industries, and in 1945 the Slinky hit shelves. By the end of the 20th century, around 250 million Slinkys had been sold.
Penicillin was discovered in 1928 by the Scottish bacteriologist Alexander Fleming, and it was later isolated and purified in the late 1930s. Making large amounts of penicillin, however, was difficult. In 1942, when the new antibiotic was first used to successfully treat a patient for sepsis, it used up half the available supply of penicillin in the United States. During the war, a combined effort between the U.S. and Great Britain saw scientists working around the clock to develop mass production techniques. They were successful, and managed to manufacture 2.3 million doses of penicillin in preparation for the D-Day invasion on June 6, 1944.