Is the time now ripe for planes to run on hydrogen?

IN THE SWAMPS of 1950s Florida, a loud roaring occasionally disturbed the serenity of the local alligators. Under conditions of strictest secrecy, engineers from Pratt & Whitney, an aerospace company, were testing a new type of engine that was powered by a strange substance apparently piped in from a fertiliser plant in the nearby town of Apix. In reality, the town was just a name on a map and the fertiliser plant was a ruse to fool the Russians. The disturbances were the result of Project Suntan, an attempt by America’s air force to build a plane fuelled with hydrogen. It nearly worked. The engines operated successfully, but storing and supplying the hydrogen itself proved too expensive for production to continue.Suntan was just the first of a string of failed attempts to use hydrogen to power heavier-than-air flight. The allure is great. Hydrogen packs three times as much energy per kilogram as kerosene, the current standard aviation fuel, and lightness is at a premium aloft. Tupolev, in what was then the Soviet Union, tried in the 1980s. Boeing tried in the 2000s. A small demonstrator has flown in Germany. But nothing has, as it were, really taken off. Hydrogen, though light, is bulky, making it awkward to store on board. It must be either pressurised or liquefied, both of which bring complications of their own. On top of that, there is no established infrastructure for making and distributing it.