Henri Giffard (1825-1882), French engineer, historical artwork. Giffard was the inventor of the first navigable, passenger-carrying airship in 1852. The steam-powered, lighter than air craft was 43 metres long and was called a dirigible. The dirigible was filled with hydrogen and flew at about 8 kilometres per hour (5 mph). It was not, however, until the invention of the gasoline-powered engine in 1896 that practical airships of a similar design could be built. Giffard also invented the injector, which fed water into a steam-engine boiler to prevent it running out of steam when not in motion.