Cobham plc is a British manufacturing company based in Wimborne Minster, Dorset, England. It is listed on the London Stock Exchange and is a constituent of the FTSE 250 Index. According to Defense News it is the 51st largest defense firm in world, and 5th largest in the UK, based on 2013 revenue. Cobham was founded as Flight Refuelling Limited (FRL) at RAF Ford in Sussex by Sir Alan Cobham in 1934. It moved to Tarrant Rushton in Dorset in 1947. It developed the 'probe and drogue' method of air-to-air refuelling in 1949 and Michael Cobham took over the leadership of the business from his father in 1969. In September 1997 it acquired ML Aviation for £37 million, which had taken over Nash & Thompson, a major competitor, the previous year.