Vertical Take-Off and Landing (VTOL) describes airplanes that can lift off vertically. This classification includes only a very few aircraft; helicopters, gyrocopters, autogyros, gyroplanes, balloons and airships are not considered VTOL. Some aircraft can operate in VTOL mode in addition to others, such as CTOL (Conventional Take-off and Landing). Others can only operate by VTOL, due to the aircraft lacking landing gear that can handle horizontal motion.

In 1928, Nikola Tesla received patents for an apparatus for aerial transportation. It is one of the earliest examples of VTOL aircraft. In the late 1950s and early 1960s almost all fighter aircraft designed included some VTOL features. This was a response to the worrying possibility that a first-strike against airfields by nuclear armed bombers would leave a country open to attack by following bombers. The "solution" was to use VTOL fighters that could be moved to open fields around the countryside, making them immune to widespread destruction.

In reality the costs of VTOL performance were huge, and while it turned out to be fairly easy to move the plane, moving the support equipment and fuel was not so easy. By the mid-1960s interest in VTOL had faded, perhaps due much to the widespread introduction of ICBMs as the main nuclear delivery system.

Currently there are believed to be two types of practical VTOL aircraft in operation:

• Bell Boeing V-22 Osprey "tilt-rotor" and the
• British Aerospace Harrier "Jump jet" (or its updated American-built counterpart, the Boeing AV-8B Harrier II)

An early VTOL prototype was the so-called "flying bedstead".

The Harrier is often flown in STOVL mode which enables it to carry a higher fuel or weapon load over a given distance. It was developed from the Hawker P.1127 and Kestrel. The Indian and Spanish Navies operate Sea Harriers, mainly from aircraft carriers.

The United States Marine Corps uses a license-built derivative of the Harrier. NASA has flown other VTOL craft such as the XV-15 research craft, as have the Soviet Navy and Luftwaffe. Sikorsky tested an aircraft dubbed the X-Wing, which took off in the manner of a helicopter. The rotors would become stationary in mid-flight, and function as wings, providing lift in addition to the static wings.

The Soviet Yak-38 Forger was the Soviet Navy's VTOL aircraft for their light carriers, cargoships, and capital ships. It was developed from the Yak-36 Freehand experimental aircraft. Before the Soviet Union collapsed, the only supersonic VTOL aircraft was developed as the Yak-38's successor, the Yak-141, which never went into production.

The Moller Skycar is a prototype personal VTOL aircraft -- literally, a "flying car".

Aircraft designed to operate in extraterrestrial environments often utilize VTOL. An example of this type of aircraft is the LLRV. Spacecraft typically operate in environments where runways or even a suitably flat surface for skids is nonexistent.

See also

• Category:VTOL aircraft List of all VTOL-Aircraft
• Military flying saucers

Internal links

• Tiltrotor
• Tiltwing
• Tailsitter