19. De Havilland Discovered That Going For Looks Instead of Functionality Was a Bad Idea
When de Havilland’s aeronautical engineers designed the Comet’s windows, they opted for large squares. There was no particular engineering or design basis for the decision: it was driven by aesthetics. Square windows simply looked better than the traditional round “porthole” style windows. It turned out to be a bad idea because – unfortunately for dozens of Comet passengers who died in a series of crashes – designers back then did not understand metal fatigue. Stresses piled up at the corners of the Comet’s square windows and caused catastrophic fuselage breaches mid-flight, which led to fatal crashes.
It took time to figure out the problem, because the Comets often broke apart at high altitudes and above water, so recovering the wreckage to examine it was difficult or impossible. Eventually, the problem was identified, and the entire Comet fleet was pulled out of service. De Havilland never recovered. While the Comet was being redesigned with round windows and thicker fuselages, the Boeing 707 and Douglas DC-8 hit the market and became hits with airliners. In hindsight, it turned out that opting for square windows was not just a run-of-the-mill bad idea, but a catastrophic idea that doomed the pioneering manufacturer.