The Handley Page 0/400 was a heavy bomber used by Great Britain during the latter half of World War 1.
Background[]
Given that powered flight was so new, Handley Page’s World War I series of large night-bombers was a remarkable achievement. The Handley Page O/400 was a refinement of the earlier 0/100, which was designed to an Admiralty specification for a dedicated bomber aircraft — at the time (1914) this was a revolutionary idea. 0/100s were operational in France in 1916, and revision of the design (increased fuel capacity and better engines) led to the hugely successful O/400 bomber. Five hundred and fifty were built in Britain and a further 100 were produced in the USA. The 0/400 was a very large aircraft, and in daylight would have been easy prey for capable German fighters. It was therefore used as a night-bomber and could carry ordnance up to the size of the 749kg/1650lb bomb, the heaviest used by the British during World War l.
Charged with attacking enemy industrial targets, the O/400s would fly in fleets of up to 40 a night. These raids were the first true strategic bombing raids in history, and the large Handley Page bombers were seen by some military leaders as the future of waging war. More than 400 O/400s operated with the Royal Air Force before the Armistice of November 1918, equipping Nos. 58, 97, 115, 207, 214, 215 and 216 Squadrons of the RAF. In August 1918 an O/400 was attached to No.1 Squadron of the Australian Flying Corps serving in the Middle East. No.1 worked with T.E. Lawrence, whose Arab associates, impressed by the sheer size of the aircraft, reportedly called it “The Father of all aeroplanes".
The type served in the RAF until late 1919, when it was replaced by the Vickers Vimy. Post-war, ten 0/400s were converted from military to civil configuration, and used in the UK by Handley Page Transport Ltd.[2]