Fore-and-aft control was by means of the elevator in front, operated by hand lever. The tail of the machine had twin movable rudders instead of a single movable rudder developed in the 1902 glider. These rudders were linked by wires to the wing-warping system. Their coordinated control mechanism was worked by wires attached to a cradle on the lower wing, in which the pilot lay prone. To turn the machine to the left, the pilot moved his body, and with it the cradle, a few inches to the left. This caused the rear right wingtips to be pulled down or warped (thus giving more lift and raising them) and the rear left wingtips to move upward, and at the same time the coordinating mechanism introduced enough left rudder to compensate for yaw. The rudder counteracted the added resistance of the wing with the greater angle and the resulting tendency of the machine to swing in the opposite direction to the desired left turn, as well as aiding the turn on its own account. [Illustration: Wright 1903 machine (rear view) in the Smithsonian Institution showing attachments on the lower wing. _Courtesy, Smithsonian Institution._] [Illustration: Plans of the Wright Brothers 1903 plane. _Courtesy, Smithsonian Institution._] [Illustration: Photograph of side view of the plane.] [Illustration: Photograph of front view of the plane.] On September 25, 1903, the Wrights arrived once more at their Kill Devil Hills camp. They repaired and again used the living quarters which they had added to the storage building in 1902, called their “summer house.” Their 1902 glider, which they had left stored in this building after that season of experiments, was again housed with them in the building. They erected a new building to house the powered machine alongside the glider-storage and living-quarters building and commenced the chore of assembling the powered machine in its new hangar. Occasionally they took the 1902 glider out for practice. After a few trials each brother was able to make a new world’s record by gliding for more than a minute. The first weeks in camp were a time of vicissitudes for the Wrights. Assembling the machine and installing the engine and propellers proved an arduous task. When tested, the motor missed so often that the vibrations twisted one of the propeller shafts and jerked the assembly apart. Both shafts had to be sent back to their Dayton bicycle shop to be made stronger. After they had been returned, one broke again, and Orville had to carry the shafts back to Dayton to make new ones of more durable material. The magneto failed to produce a strong enough spark. A stubborn problem was fastening the sprockets to the propeller shafts; the sprockets and the nuts loosened within a few seconds even when they were tightened with a 6-foot lever.