Search results
Results from the WOW.Com Content Network
A rotor blade produces more lift in the advancing half. As a blade moves toward the direction of flight, the forward motion of the aircraft increases the speed of the air flowing around the blade until it reaches a maximum when the blade is perpendicular to the relative wind. At the same time, a rotor blade in the retreating half produces less ...
Contra-rotating, also referred to as coaxial contra-rotating, is a technique whereby parts of a mechanism rotate in opposite directions about a common axis, usually to minimise the effect of torque. Examples include some aircraft propellers , resulting in the maximum power of a single piston or turboprop engine to drive two propellers in ...
Contra-rotating propellers Contra-rotating propellers on the Rolls-Royce Griffon-powered P-51XR Mustang Precious Metal at the 2014 Reno Air Races. Aircraft equipped with contra-rotating propellers (CRP) [1] coaxial contra-rotating propellers, or high-speed propellers, apply the maximum power of usually a single piston engine or turboprop engine to drive a pair of coaxial propellers in contra ...
Axial compressor animation showing rotating blades and stationary stators The 17-stage axial compressor on the General Electric J79. Air moves from left to right. Each compressor stage is a row of rotor blades which give the air tangential velocity followed by a stationary row of stator blades which slow the air and raise its static pressure.
Diagram of a fan disk Fan disk assembly diagram, showing one blade and attachment hardware Cross section of fan disk Failed fan disk recovered from the center engine of UAL 232. A fan disk is the central hub of a fan in a turbofan engine. Fan blades are attached to the fan disk, which is rotated by a shaft driven by a gas turbine. [1]
In a stationary hover, each rotor blade will experience the same airspeed at a constant RPM. In forward flight conditions, one rotor blade will be moving into the oncoming air stream while the other moves away from it. At certain airspeeds, this can create a dangerous condition in which the receding rotor blade stalls, causing unstable flight. [5]
This is done by blade flapping and cycling feathering. Blade flapping is the primary means of countering dissymmetry of lift. [1]: 2–14 Rotor blades are designed to flap: the advancing blade flaps up and develops a smaller angle of attack due to a change in relative wind vectors, thus producing less lift than a rigid blade would. Conversely ...
This is commonly accomplished by a tail rotor, coaxial rotors, and the NOTAR systems. Tandem-rotor helicopters, however, use counter-rotating rotors, with each cancelling out the other's torque. Therefore, all of the power from the engines can be used for lift, whereas a single-rotor helicopter uses some of the engine power to counter the ...