Handley Page Type O

The Handley Page Type O, commonly known as the Handley Page O/400, was a British heavy bomber that entered service during the First World War. Designed by Sir Frederick Handley Page, it first flew in June 1915 as the prototype H.P.17 and was quickly adopted by the Royal Naval Air Service, later the Royal Air Force, where it became the backbone of the strategic bombing force. The aircraft featured a twin‑engine biplane layout with a robust wooden frame, fabric covering, and a distinctive elongated fuselage that housed a crew of four to five. Its 260‑horsepower Sunbeam or Rolls‑Royce Eagle engines gave it a maximum speed of about 97 mph and a range exceeding 400 km, allowing it to carry up to 2,000 lb of bombs on long‑range raids over Germany. The Type O’s defensive armament consisted of multiple .303‑inch Lewis guns mounted in nose, dorsal, and ventral positions, providing all‑round protection. Operationally, it proved vital in the early development of strategic bombing doctrine, demonstrating the feasibility of delivering heavy payloads from considerable altitude. After the war, the Type O influenced later designs such as the Handley Page H.P.53 and set standards for large multi‑engine bombers that persisted into the interwar period.