and above the very best that British industry could be expected to produce. The extra margin was added to provide an out-of-reach target to British industry so that it would push as hard as possible to increase production. The Ministry was characterised by, for its time, highly unorthodox methods of management, including its initial location at Beaverbrook's home, Stornoway House. Personnel were recruited from outside the Air Ministry, interaction was informal, characterised by personal intervention, crisis management and application of willpower to improve output. "Few records were kept, the functions of most individuals were left undefined and business was conducted mainly over the telephone". One important change made within days of the creation of the ministry was it taking over the RAF's storage units and Maintenance Units which were found to have accepted 1,000 aircraft from the industry but issued only 650 to squadrons. These management and organisational changes bore results almost immediately; in the first four months of 1940, 2,729 aircraft were produced of which 638 were fighters, while in the following four months crucial to the Battle of Britain during May to August 1940, production rose to 4,578 aircraft, of which 1,875 were fighters. This production rate achieved was two and a half times German fighter production and the ministry repaired and return to service nearly 1,900 aircraft. The result of this effort and management style was that while the number of German fighters available for operations over England fell from 725 to 275, the RAF's complement rose from 644 at the beginning of July 1940 to 732 at the beginning of October. Beaverbrook left the Ministry at the end of April 1941. He was succeeded by John Moore-Brabazon, who was replaced in February 1942 by John Llewellin, who served until November 1942. Stafford Cripps Sir Stafford Cripps became the Minister of Aircraft Production on 22 November 1942, serving for two and a half years until the end of the war in Europe. He made a number of changes, including replacing unrealistic production targets, deliberately set too high to encourage effort, with realistic forecasts for each type of aircraft. Production levels were maintained at over 2,000 aircraft a month, with the number of heavy bombers – a priority – doubling to a monthly average of 458 by 1944. Production Efficiency Boards were established to monitor production and remove inefficiency with, in extreme cases, the Ministry taking direct control