FH.X.C.K3

From the FAA library

• Helicopter Flying Handbookp. 11-3
  Chapter 11: Helicopter Emergencies and Hazards › Autorotation › RPM Control

  Control Rotor rpm in low inertia rotor systems has been studied in simulator flight evaluations which indicate that the simultaneous application of aft cyclic, down collective, and alignment with the relative wind (trim) at a wide range of airspeeds, including ... cruise airspeeds, is critical for all operations during the entry of an autorotation. The applicable Rotorcraft Flight Manual (RFM) should be consulted to determine the appropriate procedure(s) for safely entering an autorotation. This is vitally important since the procedure…

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

  Main Rotor Transmission The primary purpose of the main rotor transmission is to reduce engine output rpm to optimum rotor rpm. This reduction is different for the various helicopters. As an example, suppose the engine rpm of a specific helicopter ... rotor speed of 450 rpm would require a 6:1 reduction. A 9:1 reduction would mean the rotor would turn at 300 rpm. Dual Tachometers Most helicopters use a dual-needle tachometer or a vertical scale instrument to show…

• 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. 11-1
  Chapter 11: Helicopter Emergencies and Hazards › Autorotation

  cause, the recovery needs to be quick and precise. By having a thorough knowledge of the helicopter and its systems, a pilot is able to handle the situation more readily. Helicopter emergencies and the proper recovery procedures should be discussed ... flight. In addition, by knowing the conditions that can lead to an emergency, many potential accidents can be avoided. Autorotation In a helicopter, an autorotative descent is a power-off maneuver in which the engine is disengaged from the main…

• Helicopter Flying Handbookp. 11-7
  Chapter 11: Helicopter Emergencies and Hazards › Common Errors › Autorotation with Turns

  Collective should be lowered to the full down position to maintain rotor rpm immediately following a loss of power. However, rapid or abrupt collective movement could lead to mast bumping in some rotorcraft with teetering rotor systems. Energy ... very important property of all rotating components, and the kinetic energy stored in the rotor system is used to cushion the landing. More lift is produced at the bottom of an autorotation by raising the collective, which increases the angle…

• Aviation Maintenance Technician Handbook - Airframep. 2-18
  Chapter 2: Aerodynamics, Aircraft Assembly, & Rigging › Forces Acting on the Helicopter › Torque Compensation

  rotor designs typically have an auxiliary rotor located on the end of the tail boom. This auxiliary rotor, generally referred to as a tail rotor, produces thrust in the direction opposite the torque reaction developed by the main rotor. [Figure ... permit the pilot to increase or decrease tail rotor thrust, as needed, to neutralize torque effect. Other methods of compensating for torque and providing directional control include the Fenestron® tail rotor system, an SUD Aviation design that employs a ducted…