The Nagler NH-160 was an experimental single seat
helicopter
A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attributes ...
with counter-rotating blades.
Design and development
Bruno Nagler began wind tunnel experiments into helicopter design in 1926 and developed the first practical
swash plate
A swashplate, also known as slant disk, was invented by Anthony Michell in 1917. It is a mechanical engineering device used to translate the motion of a rotating shaft into reciprocating motion, or vice versa. The working principle is similar to c ...
.
The Nagler NH-120 was developed to test the idea of counteracting rotor torque with a small separate rotor. The engine was mounted above the main rotor on a shaft, and the anti-torque rotor was mounted above both. The NH-160 had a conventional helicopter engine and rotor layout, with the exception of the smaller anti-torque rotor mounted under the
fuselage
The fuselage (; from the French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds crew, passengers, or cargo. In single-engine aircraft, it will usually contain an engine as well, although in some amphibious aircraft t ...
between the landing skids. Yaw control on both was effected through changing the difference in rotational speed between the two rotors, using a series of
disc brake
A disc brake is a type of brake that uses the calipers to squeeze pairs of pads against a disc or a "rotor" to create friction. This action slows the rotation of a shaft, such as a vehicle axle, either to reduce its rotational speed or to hol ...
s. A small tail surface provided directional stability in forward flight. The smaller rotor would spin at a higher rpm, with about 60 percent of the load,. the main rotor being adjustable for lift control.
The NH-160 proved to be much more stable in tests than the NH-120 which had a higher center of gravity.
Variants
;NH-120
:Helicopter with engine mounted above rotor with a counter-torque rotor mounted above the engine.
;NH-170
:An enclosed two-seat side-by-side design with a shrouded lower counter-torque rotor.
Specifications (Nagler NH-160)
See also
References
{{reflist
1950s United States helicopters
Single-engined piston helicopters