They returned to kitty Hawk in May of 1908 to flight test their modified 1905 flyer, which they equipped with upright hand controls and seats for the pilot and passenger. They were required by the Signal Corps to produce an airplane "capable of carrying two men and sufficient fuel supplies for a flight of 125 miles, with a speed of at least 40 miles an hour." They started flying on 6 May, were first witnessed flying by correspondents on 11 May, and flew their first passenger on 14 May.