British shadow factories were the outcome of the Shadow Scheme, a plan devised in 1935 and developed by the British government in the buildup to World War II to try to meet the urgent need for more aircraft using technology transfer from the motor industry to implement additional manufacturing capacity.
The term 'shadow' was not intended to mean secrecy, but rather the protected environment they would receive by being staffed by all levels of skilled motor industry people alongside (in the shadow of) their own similar civilian motor industry operations.
A directorate of Aeronautical Production was formed in March 1936 with responsibility for the manufacture of airframes as well as engines, associated equipment and armaments. The project was headed by Herbert Austin and developed by the Air Ministry under the internal project name of the Shadow Scheme. Sir Kingsley Wood took responsibility for the scheme in May 1938, on his appointment as Secretary of State for Air in place of Lord Swinton.
Many more factories were built as part of the dispersal scheme designed to reduce the risk of a total collapse of production if what would otherwise be a major facility were bombed, though these were not shadow factories.
Purpose and use It was impossible for these facilities to be secret, though they were camouflaged after hostilities began. They were war materiel production facilities built in "the shadow" of motor industry plants to facilitate technology transfer to aircraft construction and run, for a substantial management fee, in parallel under direct control of the motor industry business along with distributed facilities.S E Little and M S Grieco of Oxford University quoted in General Erhard Milch, chief administrator of the Luftwaffe, was in Britain in the autumn of 1937 inspecting new shadow factories in Birmingham and Coventry, RAF aeroplanes and airfields.Nutland, 2012 p93
Background Up until the middle of 1938, the Air Ministry had been headed by Lord Swinton. He had been forced by Prime Minister Neville Chamberlain to resign his position due to a lack of progress in re-arming the Royal Air Force, the result of obstruction by William Morris, Lord Nuffield. Swinton's civil servants approached their new boss, Sir Kingsley Wood, and showed him a series of informal questions that they had asked since 1935 on the subject, such as those posed to Morris Motors with regard to aircraft engine production capability at its Cowley plant in Oxford. As it turned out, the specialised high-output engines required by the RAF were made by Armstrong Siddeley, Bristol Aeroplane, Napier & Son and Rolls-Royce, all of which employed a high number of sub-contractors. Despite their new factories, protestations by Wolseley Aero Engines (Nuffield) and Alvis were ignored. Their products were not required. Engines were specified primarily by the designers of aircraft though the Air Ministry did sometimes specify the engine to be used. Nuffield did participate after Wood's appointment, providing the Castle Bromwich Factory and promising a thousand Spitfires by June 1940 but, after two years, management was so poor that when June 1940 arrived not one Spitfire had been produced there. Castle Bromwich was withdrawn from Nuffield by Lord Beaverbrook. the Minister of Aircraft Production, and placed under the wing of Vickers-Supermarine.
Implementation The plan had two parts: Development of nine new factories. The government would build and equip the factories. Motor car companies would be asked to gain experience in the making of engine parts so, if war broke out, the new factories could immediately go into full production. Extensions to existing factory complexes to allow either easier switching to aircraft industry capability, or production capacity expansion.
Under the plan, there was government funding for the building of these new production facilities, in the form of grants and loans. Key to the plan were the products and plans of Rolls-Royce, whose Merlin engine powered many of the key aircraft being developed by the Air Ministry, as well as Bristol Hercules radial engine. Bristol Aeroplane would not allow shadow factories to build complete engines, only components.Nutland, 2012 p45 The exception was Austin.
The first motor manufacturers chosen for engine shadows were: Austin, Daimler, Humber (Rootes Securities), Singer, Standard, Rover and Wolseley.Nutland, 2012 p65 In the event Lord Nuffield took Wolseley out of the arrangement and Singer proved to be in serious financial difficulty.
The buildings Wood handed the overall project implementation to the Directorate of Air Ministry Factories, appointing Herbert Austin to lead the initiative (most of the facilities to be developed were alongside existing motor vehicle factories), and the technical liaison with the aircraft industry to Charles Bruce-Gardner. He also handed the delivery of the key new factory in Castle Bromwich, that was contracted to deliver 1,000 new Supermarine Spitfires to the RAF by the end of 1940, to Lord Nuffield, though in May 1940 the responsibility had to be taken from Nuffield and given to Vickers.
The buildings were sheds up to long lit either by glazed roofs or "north-lit". Office accommodation was brick, and wherever possible faced a main road. These buildings were extremely adaptable and would remain part of the British industrial landscape for more than 50 years. One of the largest was Austin's Cofton Hackett, beside their Longbridge plant, started in August 1936. long and wide, the structure covered . Later a airframe factory was added, then a flight shed by was attached to the airframe factory.Nutland, 2012 p66
The new factory buildings were models of efficient factory layout. They had wide, clear gangways and good lighting, and they were free of shafting and belt drives.Nutland, 2012 p97 The five shadow factories in Coventry were all in production by the end of October 1937 and they were all making parts of the Bristol Mercury engine. By January 1938 two of those shadow factories were producing complete airframes. In July 1938 the first bomber completely built in a shadow factory (Austin's) was flown in front of Sir Kingsley Wood, Secretary of State for Air. It was said eight shadow factories constructing aircraft components were in production in or near Coventry in February 1940.
As the scheme progressed, and after the death of Austin in 1941, the Directorate of Air Ministry Factories, under the auspices of the Ministry of Aircraft Production (MAP), gradually took charge of the construction of the buildings required for aircraft production. In early 1943 the functions of the directorate of Air Ministry Factories were transferred to the Ministry of Works. Scotland There were three waves of construction of shadow factories and only the third and smallest reached Scotland in the shape of the factory at Hillington producing Rolls-Royce's Merlin engines. Ferranti's factory in Crewe Toll, Edinburgh will have been secret. Empire Similar plans were introduced in Canada, Australia, New Zealand and South Africa.
List of shadow factories