Bristow Helicopters Limited is a British civil helicopter operator originally based at Aberdeen Airport, Scotland, which is currently a part of the U.S.-based Bristow Group which in turn has its corporate headquarters in Houston, Texas, US. Bristow Helicopters was established by Alan Bristow in June 1955; two years later, it acquired its first pair of helicopters in the form of the Westland Widgeon. The company quickly expanded overseas as well as various services, including helicopter training, oil exploration, search and rescue, and charter flights. Having entered the African market in 1960, Nigeria became Bristow’s biggest profit centre during the 1970s. Entering the North Sea market, also during the 1960s, Bristow became Aberdeen Airport’s largest single employer during the 1980s and was operating the majority of offshore flights in the North Sea.