Three early helicopter designs of 1877, 19th-century illustration. At top is the twin-rotor steam-driven design by French engineer Emmanuel Dieuaide. At centre is the steam-powered design by Italian engineer Enrico Forlanini. At bottom is the compressed air-powered design by French engineer P. Castel. Forlanini's design achieved a height of 13 metres. Castel's design took off, but then crashed. Dieuaide and Castel's designs were powered through a hose from the ground. Artwork from 'Aerostation - Aviation' (1911) by French civil engineer Max de Nansouty (1854-1913), part of the 'Les merveilles de la science' series of 1867-1891 by Louis Figuier.