The first jet airliner entered service, marking the first commercial use of jet engines: the British De Havilland Comet I. But there were problems: the first disaster occurred in January 1954, when the plane broke up mid-air over the Mediterranean Sea 20 minutes after takeoff from an airport in Italy. All 36 people on board died in the accident. Then, in April, another, this time operated by South African Airways, disintegrated in mid-air, also over the Mediterranean. All 21 people on board lost their lives. The cause of the failure was later discovered: metal fatigue, exacerbated by the squared-off window design. Engineers redesigned the plane’s structure, including the addition of rounded windows, for what became the Comet 2, and that was the end of that problem.
