In 1936, before the first flight of the prototype, the Air Ministry placed an order for 310 Spitfires. However, in spite of the promises made by the Chairman of Vickers-Armstrongs (the parent company of Supermarine) that the company would be able to deliver Spitfire at a rate of five a week, it soon became clear that this would not happen. In 1936 the Supermarine company employed 500 people and was already engaged in fulfilling orders for 48 Walrus amphibian reconnaissance aircraft and 17 Stranraer patrol flying boats. In addition the small design staff, which would have to draught the blueprints for the production aircraft, was already working at full stretch.
Although it was obvious that most of the work would have to be sub-contracted to outside sources, the Vickers-Armstrongs board was reluctant to allow this to happen. When other companies were able to start building Spitfire components there were continual delays because either parts provided to them would not fit, or the blueprints were inadequate; the sub-contractors themselves faced numerous problems building components which in many cases were more advanced and complicated than anything they had faced before.
As a consequence of the delays, the RAF received the first two Spitfires off the production line in July 1938, while the first Spitfire to enter squadron service was received by 19 Squadron in early August. For a time the future of the Spitfire was in serious doubt, with the Air Ministry suggesting that the programme be abandoned and that Supermarine change over to building the Bristol Beaufighter under licence.
The managements of Supermarine and Vickers were eventually able to convince the Air Ministry that production would be sorted out and, in 1938, an order was placed with Morris Motors LImited for an additional 1,000 Spitfires to be built at huge new factory which was to be built at Castle Bromwich. This was followed in 1939 by an order for another 200 from Woolston and, only a few months later, another 450. This brought the total to 2,160, making it one of the largest orders in RAF history. Over the next three years a large number of modifications were made, most as a result of wartime experience.