Transverse rotor rotorcraft

Rotorcraft

A rotorcraft or rotary wing aircraft is a heavier-than-air flying machine that uses lift generated by wings, called rotor blades, that revolve around a mast. Several rotor blades mounted to a single mast are referred to as a rotor. The International Civil Aviation Organization defines a rotorcraft...

 have two large horizontal

Horizontal plane

In geometry, physics, astronomy, geography, and related sciences, a plane is said to be horizontal at a given point if it is perpendicular to the gradient of the gravity field at that point— in other words, if apparent gravity makes a plumb bob hang perpendicular to the plane at that point.In...

 rotor

Helicopter rotor

A helicopter main rotor or rotor system is a type of fan that is used to generate both the aerodynamic lift force that supports the weight of the helicopter, and thrust which counteracts aerodynamic drag in forward flight...

 assemblies mounted side by side.

Single rotor helicopters need a tail rotor to neutralize the twisting moment produced by the single large rotor. Tandem rotor helicopters, however, use counter-rotating rotors, with each canceling out the other's torque. Counter-rotating rotor blades won't collide with and destroy each other if they flex into the other rotor's pathway.

This configuration also has the advantage of being able to hold more weight with shorter blades, since there are two sets. Also, all of the power from the engines can be used for lift, whereas a single rotor helicopter uses power to counter the torque.

List of transverse rotor rotorcraft

Tranverse-mounted helicopters

• Focke-Wulf Fw 61
  Focke-Wulf Fw 61
  |-See also:-References:NotesBibliography* Coates, Steve and Jean-Christophe Carbonel. Helicopters of the Third Reich. Crowborough, UK: Classic Publications Ltd., 2002. ISBN 1-903223-24-5....
  
   (1936)
• Focke-Achgelis Fa 223 (1941)
• Platt-LePage XR-1 (1941)
• Landgraf H-2
  Landgraf H-2
  |-See also:...
  
   (1944)
• Bratukhin G-3 (1946)
• Bratukhin B-11 (1948)
• Kamov Ka-22
  Kamov Ka-22
  |-See also:...
  
   (1959)
• Mil Mi-12 (1967)

Tranverse-mounted tiltrotors

• Bell/Agusta BA609
  Bell/Agusta BA609
  The AgustaWestland AW609, formerly the Bell/Agusta BA609, is a civil twin-engined tiltrotor VTOL aircraft with a configuration similar to the Bell-Boeing V-22 Osprey.-Design and development:...
  
  
• Bell XV-15
  Bell XV-15
  The Bell XV-15 was 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.-Early VTOL rotor aircraft:...
  
  
• Bell XV-3
  Bell XV-3
  |-See also:- References :NotesBibliography*Markman, Steve, and William G. Holder. Straight Up: A History of Vertical Flight. Schiffer military/aviation history. Atglen, PA: Schiffer Pub, 2000....
  
  
• Bell Eagle Eye
  Bell Eagle Eye
  -References:* This article contains material that originally came from the web article by Greg Goebel, which exists in the Public Domain.-External links:** * ....
  
  
• V-22 Osprey
  V-22 Osprey
  The Bell Boeing V-22 Osprey is an American multi-mission, military, tiltrotor aircraft with both a vertical takeoff and landing , and short takeoff and landing capability...
  
  

See also

• Coaxial rotors
• Intermeshing rotors
  Intermeshing rotors
  Intermeshing rotors on a helicopter are a set of two rotors turning in opposite directions, with each rotor mast mounted on the helicopter with a slight angle to the other, in a transversely symmetrical manner, so that the blades intermesh without colliding. The arrangement allows the helicopter to...
  
  
• Rotorcraft
  Rotorcraft
  A rotorcraft or rotary wing aircraft is a heavier-than-air flying machine that uses lift generated by wings, called rotor blades, that revolve around a mast. Several rotor blades mounted to a single mast are referred to as a rotor. The International Civil Aviation Organization defines a rotorcraft...
  
  
• Tandem rotors
• Tiltrotor
  Tiltrotor
  A tiltrotor is an aircraft which uses a pair or more of powered rotors mounted on rotating shafts or nacelles at the end of a fixed wing for lift and propulsion, and combines the vertical lift capability of a helicopter with the speed and range of a conventional fixed-wing aircraft...