In 2023, very few people can claim to have flown on a supersonic airliner, but for a while in the 1960s, it looked as if futuristic planes like the Concord would be a common mode of air travel. In the end, though, it was the comparatively slower airliners like the Boeing 747 that "shrank the world," while Concord proved to be a one-off. It was the gilded carriage of a privileged few, operating on a handful of prestige routes until retiring in the early 2000s. Why didn't supersonic airliners catch on? Simply put, they weren't economical. The high drag experienced by planes at Mach 1 and above imposes enormous fuel costs, while the smaller cabins could carry only a fraction of the passengers accommodated in slower "wide-body" planes. After the oil crisis of the early 1970s, airlines lost their appetite for gas-guzzling planes. Rather than focusing on getting passengers from A to B as quickly as possible, they needed to figure out how to do it cheaply . For aircraft designers, this meant developing a new wing design optimized for high subsonic flight, where conventional airliners are already most economical. In the early 1960s, aeronautical engineer Dr. Richard T. Whitcomb started working on the problem of economical high-speed flight, specifically, on a so-called "supercritical" wing. to reduce drag. The speed which this occurs is known as the "critical" speed, according to NASA . A "supercritical" wing is designed to halt formation of a shock wave, thereby creating less drag, better controllability, and reduced fuel consumption.