Powered lift

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A powered lift (also written powered-lift) is a type of aircraft that can take off and land vertically but functions differently than a helicopter in horizontal flight.

1 Definition
2 Aircraft models
3 References
4 See also

[edit] Definition

In the United States, the Federal Aviation Administration (FAA) has designated seven categories of aircraft:

Airplane
Rotorcraft
Glider
Lighter-Than-Air
Powered-Lift
Powered parachute
Weight-shift-control

The FAA defines "powered-lift" as:

a heavier-than-air aircraft capable of vertical takeoff, vertical landing, and low speed flight that depends principally on engine-driven lift devices or engine thrust for lift during these flight regimes and on nonrotating airfoil(s) for lift during horizontal flight.^[1]

The first powered-lift ratings to be issued on a civilian pilot certificate were issued on 21 August 1997 by the FAA to pilots Tom Macdonald of Bell Boeing; William Leonard and Martin Shubert of Bell Helicopter; William Norton and Steve Grohsmeyer of Boeing; and Lt. Col. John Rudzis, Maj. Kevin Gross, and Capt. William Witzig of the United States Marine Corps.^[2]

[edit] Aircraft models

Many powered lift aircraft have been tested but very few have been mass-produced. They differ in their means of achieving vertical takeoff and landing.

The V-22 Osprey uses aerodynamic lift (the aircraft is kept in the air by rotors; see aerodynamics).
The Harrier Jump Jet family uses engine lift (rising off the ground by use of vertical thrust).

See related article: Aircraft#Categories and classification.

[edit] V-22 Osprey

in construction is the V-22 Osprey by Bell Boeing, a twin-engine tiltrotor design that has two turbine-powered engines driving three-bladed rotors. The rotors function similar to a helicopter in vertical flight, and similar to an airplane in forward flight. The aircraft first flew on 19 March 1989. Bell Boeing comprises Bell Helicopter of Fort Worth, Texas, a wholly owned subsidiary of Textron, Inc., and the Boeing Aircraft Corporation in Philadelphia.

[edit] Harrier Jump Jet

The Harrier Jump Jet covers a series of a military VSTOL jet aircraft. It is capable of vertical/short takeoff and landing (V/STOL) and is the only truly successful design of this type from the many that arose in the 1960s. These aircraft are capaple of operating from small spaces,such as fields, roads, and aviation-capable ships.

There are four main versions of the Harrier Jump Jet.

[edit] Bell/Agusta 609 Tiltrotor

The Bell/Agusta BA609 tiltrotor is the evolution of Bell Helicopter's V-22 Osprey into a civilian aircraft. The Aircraft can take off and land vertically with 2 crew and 9 passengers, and within 20 seconds, transition to forward flight (by tilting its rotorblades into a fully forward position, much like the V-22 Osprey). In forward flight it can cruise at speeds of up to 275 knots (509 km/h), with a range exceeding 1,000 nautical miles (with long-range fuel tanks). It is rated to fly above FL210 (21,000 ft), has a maximum payload capacity of over 5,500 pounds, thanks to two Pratt and Whitney PT6C-67A turbines rated at 1,940 shp, each driving a 26-foot (8 m) diameter 3-bladed rotor blade. The aircraft is not yet in full production; however, many have expressed interest, and the waiting list for orders is already years long.

[edit] References

^ Federal Aviation Regulations Part 1 on www.faa.gov
^ news release "Osprey Pilots Receive First FAA Powered Lift Ratings" dated 21 August 1997 at www.boeing.com