troop carriers as used by the Handley Page Clive. A further change was made in 1932 and 1939 to use more appropriate names. Fighters were to use "General words indicating speed, activity or aggressiveness" and trainer would be "words indicationg tuition and places of education". Bombers were to be named after inland towns in the British Empire, for example the Avro Lancaster and Fairey Battle (after Battle, East Sussex, the site of the Battle of Hastings). With the introduction of helicopters these were to be named after trees but only the Bristol Sycamore was named in this scheme. Names The name ("type name") of an aircraft type would be agreed between the Air Ministry or Admiralty and the manufacturer/importer when the order was placed. Names generally followed one or a number of patterns: Alliteration was particularly common; e.g. aircraft from Vickers-Armstrongs were given names starting with V, Hawker Aircraft, names starting with H, etc. This began during the First World War, when aircraft manufacturers were given an initial pairing of letters to use in the naming of their aircraft: e.g. Boulton Paul Ltd were given "Bo". From this and the requirement to use the names of birds or insects for fighter aircraft, their first in-house fighter design was the Boulton Paul Bobolink. For bombers the additional requirement was a placename, hence the Boulton Paul Bourges; and its contemporaries – the Airco DH.10 Amiens and Vickers Vimy (Bourges, Amiens and Vimy all being in France). Heavy bombers received the names of cities and towns – Short Stirling, Avro Lancaster, Handley Page Halifax. Likewise transport aircraft also received the names of cities and towns – Avro York, Vickers Valetta, Handley Page Hastings, Blackburn Beverley. Flying boats were given the names of coastal or port communities – Saro London, Supermarine Stranraer, Short Sunderland. Land-based maritime patrol aircraft were named for naval explorers – Avro Anson (George Anson, 1st Baron Anson), Lockheed Hudson (Henry Hudson), Avro Shackleton (Ernest Shackleton), Bristol Beaufort (Francis Beaufort). Aircraft for army co-operation and liaison and gliders were given names associated with mythological or legendary leaders; e.g. Westland Lysander, Airspeed Horsa, General Aircraft Hamilcar, Slingsby Hengist. A sense of irony was present when some of the names were chosen as Hengist and Horsa were the mythical leaders when the Angles, Saxons and Jutes invaded the British Isles in the 5th century. American aircraft, whether purchased directly or sourced under Lend-Lease,