The Ryan X-13 "Vertijet" was an experimental program of the 1950s funded by the United States Air Force to help test the validity of an aircraft that could takeoff vertically, achieve horizontal flight and land vertically - all under turbojet power. In 1947, the Bureau of Aeronautics - under the banner of the United States Navy - contracted Ryan Aeronautical to oversee development of such an airframe for use aboard American submarines. Ryan delivered promising results with ensuing trials of a tethered test and a flying design. By this time, the United States Air Force became interested in the Vertical Take-Off and Landing (VTOL) concept and contracted Ryan Aeronautical to produce a pair of prototypes under the designation of "X-13".
Development of the X-13 centered around a single-seat, single-engine airframe that could be launched from a specially designed launched trailer. The trailer bed could be raised to a vertical position and become a launch tower for the aircraft. From this position, the pilot could then guide the X-13 upwards and away from the tower, achieve a sustainable altitude and roll forwards to achieve horizontal flight. The X-13 could then be guided back from its horizontal status to a vertical one, set against the launch tower and brought to rest., completing the full flight cycle.
First flight of the X-13 was on December 10th, 1955 and this prototype was equipped with a temporary tricycle landing gear for she was intended to test only conventional flight characteristics before the program progressed to the VTOL stage. A temporary rig was then installed at the tail section before a May 28th, 1956 flight that saw the X-13 achieve full vertical flight while testing hover capabilities of the airframe and engine. It was not until April 11th, 1957 that the X-13 went on to complete its first full-cycle flight - that is, the X-13 launched from a vertical position, achieved horizontal flight and returned to its launch tower in a vertical landing. This feat occurred out of Edwards Air Force Base in California and consisted of several minutes of horizontal flight. The X-13 was publicly demonstrated in July of 1957 when a prototype flew over the Potomac River and came to rest on the Pentagon grounds.
Despite the promising nature of the X-13 project and all of its technological gains, the United States Air Force elected not to pursue the design for it lacked any requirement at the time that called for such an aircraft. Regardless, the Ryan X-13 Vertijet proved the concept sound and it was not until the British completed their long-term development of their own VTOL design that would become the "Harrier" jump jet that the dedicated VTOL aircraft was truly realized.
The X-13 prototypes showcased a length of 23 feet, 5 inches with a wingspan equal to 21 feet. Height was 15 feet, 2 inches. When empty, the X-13 displaced at 5,334lbs and 6,730lbs when full. Maximum take-off weight was in the vicinity of 7,200lbs. Power was supplied by a British Rolls-Royce Avon turbojet engine delivering up to 10,000lbf of thrust. This supplied the airframe with a maximum speed of up to 350 miles per hour and a range of 192 miles. Service ceiling was limited to 20,000 feet. Pitch and yaw was handled by the vectored engine design while "puffer" jets installed at the wing tips controlled roll.
Externally, the Ryan X-13 displayed a unique appearance as a rather squat, delta-winged creation. The wings sat high above the stubby fuselage and extended from rear of the cockpit to the engine exhaust ring. At the ends of each wing were vertical fins. The engine was buried within the oblong, tubular fuselage with intake openings to either side of the cockpit. The cockpit was situated well ahead in the fuselage and sported a framed canopy with good look-down capability over the nose and to the sides of the aircraft. Seating was for a single operator. A rod was installed in the nose to facilitate vertical alignment of the aircraft with the respective launch tower. The empennage was dominated by a single large vertical tail fin. As the X-13 was intended for vertical flight, the finalized prototype forms lacked a conventional undercarriage and instead made use of a hook-type installation under the nose and a framework of struts under the airframe body. Both assemblies were used to hold the X-13 against the launch tower/carriage when set to vertically launch or land.
The pair of completed prototypes were retired for museum use with the first (54-1619) being displayed at the San Diego Air & Space Museum and the second (54-1620) shipped to the National Museum of the United States Air Force in Dayton, Ohio. The latter prototype was the Vertijet that successfully completed the full-cycle flight and arrived at the museum in 1959.