HI.XI.G.K5

From the FAA library

• Helicopter Flying Handbookp. 4-11
  Chapter 4: Helicopter Components, Sections, and Systems › Transmission System › Dual Tachometers

  NR) on the left and engine rpm (NP) on the right side of the vertical scale. Corresponding color limits are present for each component parameter. Structural Design In helicopters with horizontally mounted engines, another purpose of the main rotor transmission…

• Helicopter Flying Handbookp. 11-20
  Chapter 11: Helicopter Emergencies and Hazards › System Malfunctions › Main Rotor Disk Interference (285–315°)

  Main Rotor Disk Interference (285–315°) Refer to Figure 11-9. Winds at velocities of 10–30 knots from the left front cause the main rotor vortex to be blown into the tail rotor by the relative wind. This main ... rotor disk vortex causes the tail rotor to operate in an extremely turbulent environment. During a right turn, the tail rotor experiences a reduction of thrust as it comes into the area of the main rotor disk vortex. The reduction…

• Helicopter Flying Handbookp. 4-4
  Chapter 4: Helicopter Components, Sections, and Systems › Main Rotor System › Rigid Rotor System

  Figure 4-4. Four-blade hingeless (rigid) main rotor. Rotor blades are comprised of glass fiber reinforced material. The hub is a single piece of forged rigid titanium. The rigid rotor system is very responsive and is usually not susceptible ... mast bumping like the semirigid systems because the rotor hubs are mounted solid to the main rotor mast. This allows the rotor and fuselage to move together as one entity and eliminates much of the oscillation usually present…

• Helicopter Flying Handbookp. 4-2
  Chapter 4: Helicopter Components, Sections, and Systems › Main Rotor System

  Main Rotor System The rotor system is the rotating part of a helicopter which generates lift. The rotor consists of a mast, hub, and rotor blades. The mast is a hollow cylindrical metal shaft which extends upwards from ... driven and sometimes supported by the transmission. At the top of the mast is the attachment point for the rotor blades called the hub. The rotor blades are then attached to the hub by any number of different methods. Main…

• Helicopter Flying Handbookp. 1-4
  Chapter 1: Introduction to the Helicopter › Rotor System › Tandem Rotor

  Tandem Rotor Tandem rotor (sometimes referred to as dual rotor) helicopters have two large horizontal rotor assemblies, instead of one main assembly and a smaller tail rotor. [Figure 1-6] Single rotor helicopters need a tail rotor to neutralize ... twisting momentum produced by the single large rotor. Tandem rotor helicopters, however, use counter-rotating rotors, each canceling out the other’s torque. Counter-rotating rotor blades will not collide with and destroy each other if they flex into…

• Helicopter Flying Handbookp. 2-15
  Chapter 2: Aerodynamics of Flight › Hovering Flight › Translating Tendency (Drift)

  Translating Tendency (Drift) During hovering flight, a single main rotor helicopter tends to move in the direction of tail rotor thrust. This lateral (or sideward) movement is called translating tendency. [Figure 2-27] To counteract this tendency, one or more ... following features may be used. All examples are for a counterclockwise rotating main rotor disk. Figure 2-27. A tail rotor is designed to produce thrust in a direction opposite torque. The thrust produced by the tail rotor is sufficient…