Hi, in conversation this week, a chap mentioned that his mother used to work in the drawing office of an aircraft company called Blackburn (not sure of spelling and might have an extra 'e') before WWII.
She was living in Muswell Hill, North London at the time and so it must have been close and available by public transport. At the outbreak, she went to a drawing office in the Ministry of War and he knew nothing more than the aircraft company.
Ring any bells? (or should that be, push any pencils?)