Concorde

For 27 years Concorde was the future made real: a slender white delta with a drooping nose that carried a hundred passengers across the Atlantic at twice the speed of sound, London to New York in about three and a half hours. It was a feat of national engineering pride for Britain and France, and a flying symbol of a coming age when everyone would travel supersonic.

That age never arrived. Only 20 Concordes were ever built and just 14 flew commercially; the planes were thirsty, deafeningly loud, and astronomically expensive to maintain. The turning point was the crash of Air France Flight 4590 in July 2000, killing 113 people — its only fatal accident — after a strip of metal on the runway burst a tyre. Passenger confidence never fully recovered, and the post-9/11 travel slump finished the economics. On 24 October 2003 Concorde flew its last commercial flight, and humanity, having once flown at Mach 2 as a matter of routine, went back to subsonic and has stayed there since.