The Handley Page Type O was a biplane bomber used by Britain during the First World War. When built, the Type O was the largest aircraft that had been built in the UK and one of the largest in the world. There were two main variants, the Handley Page O/100 (H.P.11) and the Handley Page O/400 (H.P.12).
The aircraft were used in France for tactical night attacks on targets in German-occupied France and Belgium and for strategic bombing of industrial and transport targets in the Rhineland. Some aircraft were temporarily diverted to anti-submarine reconnaissance and bombing in the Tees estuary in 1917 and two aircraft operated in the eastern Mediterranean. The impression made by the Type O was such that for many years after the war any large aircraft came to be called a "Handley Page" in Britain and entered the dictionary as such.
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