While World War II raged, pioneering aircraft and engine designers were busy developing the world's first practical jet-powered research aircraft to test and prove the new technology. This book examines the aircraft that paved the way for Germany's Me 262 and Britain's Meteor - the world's first jet fighters. Throughout the war, Germany, Italy and Britain engaged in top-secret jet programmes as they raced to develop the airpower of the future. Various experimental aircraft were trialled in order to achieve the goal of producing an effective engine and fighter that could harness the potential of the jet power. These included the German Heinkel He 178 research aircraft and Heinkel He 280 jet fighter prototype, the famed British E.28/39 research aircraft built by Gloster Aircraft as well as the stillborn E.5/42 fighter and E.1/44 Ace fighter prototype, and finally the remarkable Italian Caproni-Campini N.1/CC 2 research aircraft. Illustrated throughout with full-colour artwork and rare photographs, this fascinating study examines the fore-runners to the military jet age.