Transverse rotor

aircraft An aircraft is a vehicle that is able to flight, fly by gaining support from the Atmosphere of Earth, air. It counters the force of gravity by using either Buoyancy, static lift or by using the Lift (force), dynamic lift of an airfoil, or in ...

have two large horizontal rotor assemblies mounted side by side. Single-rotor helicopters (unicopters) need an additional tail rotor or tail exhaust to neutralize the reactional

angular momentum In physics, angular momentum (rarely, moment of momentum or rotational momentum) is the rotational analog of linear momentum. It is an important physical quantity because it is a conserved quantity—the total angular momentum of a closed syst ...

produced by the main rotor. Transverse rotor helicopters, however, use counter-rotating rotors, with each cancelling out the other's torque. Counter-rotating rotor blades also won't collide with and destroy each other if they flex into the other rotor's pathway. In addition, transverse rotor configuration has the advantage of higher payload with shorter blades, since there are two sets working to provide lift. Also, all of the power from the engines can be used for lift, whereas a single-rotor helicopter must divert part of its engine power to generate tail

thrust Thrust is a reaction force described quantitatively by Newton's third law. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction to be applied to that ...

. Transverse rotor design with rotatable

nacelle A nacelle ( ) is a "streamlined body, sized according to what it contains", such as an engine, fuel, or equipment on an aircraft. When attached by a pylon entirely outside the airframe, it is sometimes called a pod, in which case it is attache ...

s are known as tiltrotors while designs where the whole wing rotates are known as tiltwings.

List of transverse rotor aircraft

Transverse-mounted helicopters

Bratukhin B-11 The Bratukhin B-11 was a prototype Soviet twin-rotor transport helicopter and the last design of the Bratukhin Bratukhin, or OKB-3, was a Soviet aircraft design bureau created in 1940 from within TsAGI to develop helicopters. Headed by Ivan Pavlo ...

(1948) * Bratukhin G-3 (1946) *

Cierva W.5 The Cierva W.5 was a helicopter developed by the Cierva Autogiro Company in the United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the ...

(1938) * Cierva W.11 Air Horse (1948) - a three rotor helicopter * Firth Helicopter (1952) *

Focke-Achgelis Fa 223 Drache The Focke-Achgelis Fa 223 ''Drache'' () was a helicopter developed by Germany during World War II. A single Bramo 323 radial engine powered two three-bladed rotors mounted on twin booms on either side of the cylindrical fuselage. Although th ...

(1941) * Focke-Wulf Fw 61 (1936) *

Kamov Ka-22 The Kamov Ka-22 ''Vintokryl'' (rotor-wing, or literally, (air)screw-wing) (Cyrillic:Камов Ка-22 Винтокрыл) (NATO reporting name: Hoop) was a rotorcraft developed by Kamov for the Soviet Air Force. The experimental transport aircr ...

(1959) * Kamov V-100 (1980s) - unbuilt project *

Landgraf H-2 The Landgraf H-2 was an American single-seat twin-rotor helicopter designed by Fred Landgraf and built by the Landgraf Helicopter Company of Los Angeles, California. Although awarded a development contract by the United States Army, it was not de ...

(1944) *

McDonnell XHJH Whirlaway The McDonnell XHJH Whirlaway, aka McDonnell Model 65, was a 1940s American experimental transverse-rotor helicopter designed and built by McDonnell Aircraft Corporation for the United States Navy and was the largest helicopter at the time, as we ...

(1946) * Mil Mi-12 (1967) *

Platt-LePage XR-1 The Platt-LePage XR-1, also known by the company designation PL-3,Francillon 1990, p.49. was an early American transverse rotors helicopter, built by the Platt-LePage Aircraft Company of Eddystone, Pennsylvania. The winner of a United States Ar ...

(1941)

Transverse-mounted tiltrotors

* AgustaWestland AW609 * Bell Eagle Eye * Bell XV-3 *

Bell XV-15 The Bell XV-15 is an American tiltrotor VTOL aircraft. It was the second successful experimental tiltrotor aircraft and the first to demonstrate the concept's high speed performance relative to conventional helicopters. Development Early VTOL ...

* Bell Boeing V-22 Osprey

Transverse-mounted tiltwings

Canadair CL-84 Dynavert The Canadair CL-84 "Dynavert", designated by the Canadian Forces as the CX-131, was a V/STOL turbine tiltwing monoplane designed and manufactured by Canadair between 1964 and 1972. Only four of these experimental aircraft were built with three ...

List of transverse rotor aircraft

Transverse-mounted helicopters

Transverse-mounted tiltrotors

Transverse-mounted tiltwings

See also