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 famous for the geodetic framework of the Wellington bomber and for the bouncing bomb. His principal assistant (the "Chief Calculator"), Nevil Shute Norway, later well known as the novelist Nevil Shute, much later gave his account of the design and construction of the two airships in his autobiography, "", first published in 1954. Shute's book characterises R100 as a pragmatic and conservative design, and R101 as extravagant and over-ambitious, but one purpose of having two design teams was to test different approaches, with R101 deliberately intended to extend the limits of existing technology. According to Masefield, Shute later admitted that