Empire of the Clouds story of the R101 airship, which crashed on its maiden voyage in northern France on 5 October 1930. The song was written entirely by the band's lead vocalist, Bruce Dickinson, who initially intended it to be about "World War I fighter airplanes;" Dickinson abandoned the idea after using the same theme for the song "Death or Glory," also from "The Book of Souls". At the time of recording, Dickinson was reading "a big, sort of encyclopedic crash report" of the R101, entitled "To Ride the Storm", which gave him the idea for the song's eventual subject. Dickinson describes it as
R101 day R101 slipped the mast at 10:33 to carry out an endurance trial, planned to last at least thirty hours. R101 passed over York and Durham before crossing the coast and flying over the North Sea as far north as Edinburgh, where it turned west towards Glasgow. During the night a series of turning trials were made over the Irish Sea, after which the airship was flown south to fly over Dublin (the home town of R101's Captain, Carmichael Irwin) before returning to Cardington via Anglesey and Chester. After some delay in finding Cardington owing to fog, R101 was secured