In the 1930s the world was opened up for airline passengers, and the flying boat took pride of place in the development of new routes. First came the largest aircraft in the world, the 12-engined German Dornier flying boat, soon to be followed by the graceful Empire flying boats of Imperial Airways. David Lomax continues the story until 1939 when the transatlantic service was started, only to be sharply interrupted by war - when the flying boat had a new role to play.