vertical takeoff and landing

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Related to vertical takeoff and landing: VSTOL

vertical takeoff and landing

[′vərd·ə·kəl ′tāk‚ȯf ən ′land·iŋ]
(aerospace engineering)
A flight technique in which an aircraft rises directly into the air and settles vertically onto the ground. Abbreviated VTOL.

Vertical takeoff and landing (VTOL)

A flight technique in which an aircraft rises directly into the air and settles vertically onto the ground. Such aircraft do not need runways but can operate from a small pad or, in some cases, from an unprepared site. The helicopter was the first aircraft that could hover and take off and land vertically, and is now the most widely used VTOL concept. See Helicopter

The helicopter is ideally suited for hovering flight, but in cruise its rotor must move essentially edgewise through the air, causing vibration, high drag, and large power losses. The aerodynamic efficiency of the helicopter in cruising flight is only about one-quarter of that of a good conventional airplane. The success of the helicopter in spite of these deficiencies started a wide-ranging study of aircraft concepts that could take off like a helicopter and cruise like an airplane. The term VTOL is usually used to designate the aircraft other than the helicopter that can take off and land vertically. The term V/STOL indicates an aircraft that can take off vertically when necessary, but can also use a short running takeoff, when space is available, to lift a greater load. See Short takeoff and landing (STOL)

The tiltrotor is closest to the conventional helicopter and relies heavily on helicopter technology. The rotor disks are horizontal in VTOL operation and are tilted 90° to act as propellers in cruising flight. Such aircraft can have cruise efficiencies at least twice those of the helicopter, making them especially useful for helicopter missions where greater range, speed, and time on station are desired.

Numerous advanced rotorcraft concepts are being investigated in research programs. These include designs that take off and land as a rotor system and fix the blades to act as wings for cruise flight. Other concepts feature tiltrotor technology for vertical flight, but fold the blades and employ other propulsion modes for cruise.

The vectored-thrust concept features an engine with four rotating nozzles that deflect the thrust from horizontal for conventional flight to vertical for VTOL operation. This activity led to the very successful British Harrier aircraft, which is considered to be a V/STOL aircraft because its normal mode of operation is to use a short takeoff run, when space is available, to greatly increase its payload and range capability.

With the success of the Harrier, design studies and technology development programs have been directed at expanding the flight envelope of this class of aircraft to include supersonic capability. The term STOVL (short takeoff vertical landing) is used to define this supersonic fighter-attack aircraft since the large benefits in payload and range of a short takeoff will be factored into the basic design.

vertical takeoff and landing (VTOL)

The capability of an aircraft to take off and land vertically and to transfer to or from forward motion at heights required to clear surrounding obstacles.
References in periodicals archive ?
DARPA said, "For generations, new designs for vertical takeoff and landing aircraft have remained unable to increase top speed without sacrificing range, efficiency or the ability to do useful work.
The agency has already provided funds to four companies to build vertical takeoff and landing (VTOL) airplanes, as part of the DARPA's VTOL Experimental Plane (VTOL X-Plane) program.
Phantom Swift, a prototype Boeing initially built in less than a month, has been accepted to be part of the Defense Advanced Research Project Agency (DARPA) Vertical Takeoff and Landing (VTOL) X-plane program.
PALMDALE - After making its first vertical takeoff and landing, Lockheed Martin's X-35B joint strike fighter will next be tested at shifting back and forth from conventional to vertical flight.
About Moller: Moller International was formed in 1983 and is the developer of the Skycar(R), a four-person Vertical Takeoff and Landing Aircraft currently undergoing initial flight-testing.
An American multi-mission, military, tiltrotor aircraft, the Bell Boeing V-22 Osprey has a vertical takeoff and landing (VTOL), and short takeoff and landing (STOL) capability.
X-vehicles are what is going to turn us into a space transportation excellence country,'' Jess Sponable, former Air Force program manager of DC-X, which investigated vertical takeoff and landing spacecraft, told an audience at the weekend Space Frontier Conference in Los Angeles.
The Rotapower(R) engine was originally developed by Moller International (MI) for its Skycar(R) aircraft, a four-person Personal Air Vehicle (PAV) designed for both Vertical Takeoff and Landing Vehicle (VTOL) and high-speed (350 mph) forward flight.
OTCBB:MLER), the developer of the vertical takeoff and landing concept vehicle called the Skycar(R), today announced that it has engaged Malone & Bailey, PC as its independent registered public accounting firm for its fiscal year ending December 31, 2006.
BAE Systems recently demonstrated its vertical takeoff and landing unmanned aerial system (UAS) at Fort Benning, Ga.
SAN DIEGO -- Cubic Defense Applications, the defense segment of Cubic Corporation (AMEX:CUB) has received an $11 million contract from Northrop Grumman Integrated Systems to provide its Tactical Common Data Link (TCDL) for the Navy's MQ-8B Fire Scout Vertical Takeoff and Landing Unmanned Air Vehicle (VTUAV).
The company's vertical takeoff and landing (VTOL) air vehicle completed a course of 10 waypoints at BAE Systems' Southern California flight test facility.
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