Ryan X-13 Vertijet
The X-13 was designed to explore the feasibility of building a pure-jet vertical takeoff and landing (VTOL) fighter aircraft. Secondary purposes included validating several Ryan designed VTOL control system concepts.
Ryan produced the X-13 Vertijet and XV-5 VTOL aircraft for the USAF. The X-13 was a ‘tail-sitter in the mould of the Convair XFY-1 and Lockheed XFV-1, though in this instance configured as a pure research type powered by a single 10,000-lb (4536-kg) Rolls-Royce Avon turbojet. The aeroplane first flew in conventional mode with temporary wheeled landing gear on 10 December 1955, and in ‘tail-sitter’ mode during May 1956.
The seat tilted forward 45 degrees to give the pilot a more comfortable position during vertical flight. Many early flights were made with no canopy. As first built, the X-13 had a huge fin, its height nearly as great as the wingspan. This was shortened during later testing.
The success and efficiency of the X-13 flight test program provided a significant amount of data to the designers of subsequent VTOL aircraft designs. The X-13s proved that vertical flight, on jet thrust alone, was both technically feasible and practical. The ease with which the aircraft routinely transitioned from vertical to horizontal attitude, and back again, left little question as to the flexibility and operational utility of such flight modes.
The delta-winged X-13 used a unique landing method, involving a special trailer, a hook and a striped pole. To land the pilot had to approach the trailer's vertical base board without being able to see it. A pole marked with gradations protruded from the board and the pilot had to use this to judge his 'altitude' from the landing wire. In one demonstration at the Pentagon, the X-13 flew from its trailer, crossed the Potomac River, destroyed a rose garden with its thrust and landed in a net. Although this impressed the top brass, further funding was not forthcoming and the project petered out.
The last flight was made on 30 July 1957.
Fastest Flight: 483 mph (approx)
Highest Flight: 10,000 feet (approx)
Both X-13s survived their test program. The first aircraft is on loan from the National Air and Space
Museum to the San Diego Aerospace Museum in California. The second aircraft is on display at the Air
Force Museum in Dayton, Ohio.
Engine: 1 x 4540kg Rolls-Royce Avon RA.28-49 turbojet
Max take-off weight: 3317 kg / 7313 lb
Wingspan: 6.40 m / 21 ft 0 in
Length: 7.13 m / 23 ft 5 in
Height: 4.60 m / 15 ft 1 in
Max. speed: 777 km/h / 483 mph