The decision to cast Billy Campbell as Cliff Secord caused mixed emotions among Disney executives. Director Joe Johnston and creator Dave Stevens believed Campbell was perfect for the role, but Disney wanted an A-list actor. Johnston eventually convinced Disney otherwise. Campbell was not familiar with the comic book when he got the part but quickly read it, in addition to books on aviation. He also prepared by listening to 1940s period music. The actor had a fear of flying but overcame it with the help of the film's aerial coordinator, Craig Hosking. To ensure his safety, Campbell was doubled for almost all of the flying sequences in conventional aircraft. Ultimately, a scale model devised by ILM puppeteer Tom St. Amand was used for all the rocket pack scenes.