 In August 1936, an initial order for 180 "Wellington Mk I" aircraft, powered by a pair of 1,050 hp (780 kW) Bristol Pegasus radial engines, was received by Vickers; it had been placed so rapidly that the order occurred prior to the first meeting intended to decide the details of the production aircraft.In October 1937, another order for a further 100 Wellington Mk Is, produced by the Gloster Aircraft Company, was issued; it was followed by an order for 100 "Wellington Mk II" aircraft, which were instead powered by a pair of Rolls-Royce Merlin X V12 engines.Yet another order was placed for 64 Wellingtons produced by Armstrong Whitworth Aircraft.