From December 1978 to May 1980, Braniff International Airways leased 11 Concordes, five from Air France and six from British Airways.[171] These were used on subsonic flights between Dallas–Fort Worth and Washington Dulles International Airport, flown by Braniff flight crews.[172] Air France and British Airways crews then took over for the continuing supersonic flights to London and Paris.[173] The aircraft were registered in both the United States and their home countries; the European registration was covered while being operated by Braniff, retaining full AF/BA liveries. The flights were not profitable and typically less than 50% booked, forcing Braniff to end its tenure as the only US Concorde operator in May 1980.[174][175]