9. The Design Blunder that Explains Why Airplanes Have Round Windows
Boeing dominated passenger plane manufacture for most of the commercial air travel era. In the early 1950s, however, reasonable people could have predicted that the future of passenger planes belonged to Britain’s de Havilland, with Boeing a distant second. The reason was the de Havilland Comet – history’s first commercial jet liner, whose prototype first flew in 1949, and that hit the market in 1952. Fast and sleek, with a pressurized cabin that was comfortable, relatively quiet, and featured large square windows, the Comet cut six hours of travel time between London and New York. It was the world’s most promising passenger plane when it made its debut.
The Comet’s designers opted for large, square windows, because of aesthetic: they looked better than the traditional round “porthole” windows. Unfortunately, designers back then did not understand metal fatigue well. Stresses piled up at the Comet’s square window corners, and caused catastrophic fuselage breaches mid-flight that led to fatal crashes. Since the Comets often broke apart at high altitudes and above water, it took time to figure out the problem. Once the culprit was identified, the entire Comet fleet was pulled out of service. De Havilland never recovered: while the Comet underwent redesigns with round windows and thicker fuselages, the Boeing 707 and Douglas DC-8 hit the market, and became hits with airliners.
