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| Foreword | |
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| Preface | |
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| Physics | |
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| Newton's Laws | |
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| Newton's First Law | |
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| Newton's Second Law | |
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| Newton's Third Law | |
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| Conclusion | |
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| Mathematical Terms | |
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| Velocity | |
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| Acceleration | |
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| Equilibrium | |
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| Gravitational Forces | |
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| Centripetal Force | |
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| Vector Quantities | |
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| Moments and Couples | |
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| Moments | |
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| Couples | |
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| Energy | |
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| Pressure Energy | |
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| Dynamic (Kinetic) Energy | |
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| Units of Measurement | |
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| Graphs | |
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| The Atmosphere | |
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| Atmospheric Pressure | |
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| Air Temperature | |
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| Combined Effects | |
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| Moisture Content | |
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| The Standard Atmosphere (ISA) | |
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| Pressure Altitude | |
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| Density Altitude | |
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| Summary | |
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| Operational Considerations | |
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| Lift | |
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| Definitions | |
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| The Lift Formula | |
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| Dynamic Energy | |
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| Summary | |
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| Indicated Airspeed and True Airspeed | |
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| Center of Pressure | |
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| Aerodynamic Center | |
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| Drag | |
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| Types of Drag | |
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| Parasite Drag | |
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| Profile Drag | |
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| Form Drag | |
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| Skin Friction | |
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| Induced Drag | |
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| Tip Vortices | |
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| Effect of Airspeed on Induced Drag | |
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| Effect of Aspect Ratio | |
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| Methods to Reduce Induced Drag | |
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| Wash-out | |
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| Tip Design | |
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| Total Drag Curve | |
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| Conclusion | |
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| Lift/Drag Ratio | |
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| Best (or Maximum) L/D Ratio | |
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| Other Factors Influencing L/D Ratio | |
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| Conclusion | |
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| Aerodynamic Forces | |
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| Definitions | |
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| Rotor Systems | |
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| Introduction | |
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| Rotational Airflow (Vr) | |
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| Blade Angle of Attack | |
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| Induced Flow | |
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| Airflow Caused by Aircraft Velocity | |
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| The Forces | |
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| Total Rotor Thrust | |
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| Rotor Drag (Torque) | |
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| Angle of Attack and the Rotor Thrust/Rotor Drag Ratio | |
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| Induced Flow and the Rotor Thrust/Rotor Drag Ratio | |
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| Inflow Angle | |
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| The Force Opposing Weight | |
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| Factors Influencing Rotor Thrust | |
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| Air Density | |
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| Rotor rpm | |
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| Blade Angle | |
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| Disc Area | |
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| Significant Aspects of High Inertia Blades | |
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| Conclusion | |
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| Rotor Blade Airfoils | |
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| Drag Factors | |
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| Stress Factors | |
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| Effect of Local Air Velocity on Blade Design | |
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| Blade Tip Speeds | |
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| Development in Blade Design | |
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| Rotor Drag (Torque) | |
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| Disc Loading Changes | |
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| Changes in Gross Weight | |
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| Changes in Altitude | |
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| Changes in Configuration | |
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| Ground Effect | |
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| Translational Lift | |
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| Summary | |
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| The Anti-Torque Rotor | |
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| Anti-Torque Functions | |
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| Mechanical Considerations | |
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| Anti-Torque and Demand for Power | |
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| Effect of the Wind | |
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| Translating Tendency (Tail Rotor Drift) | |
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| Rolling Tendency | |
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| Tail Rotor Flapping | |
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| Shrouded Tail Rotors | |
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| Tail Rotor Design | |
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| Other Methods of Anti-Torque Control | |
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| Strakes and Anti-Torque | |
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| Tail Rotor Failure | |
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| Controls and Their Effects | |
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| Collective Control | |
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| Cyclic Control | |
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| Effect of Controls on Blade Lead-Lag Behavior | |
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| Mean Lag Position | |
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| The Four Main Causes of Movement about the Lead/Lag Hinge | |
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| Conservation of Angular Momentum (Coriolis Effect) | |
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| Hookes Joint Effect | |
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| Periodic Drag Changes | |
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| Random Changes | |
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| The Hover | |
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| Hover Our-of Ground Effect (OGE) and In-Ground Effect (IGE) | |
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| Factors Affecting Ground Effect | |
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| Helicopter Height Above Ground Level | |
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| Density Altitude and Gross Weight | |
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| Gross Weight and Power Required | |
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| Nature of the Surface | |
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| Slope | |
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| Wind Effect | |
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| Confined Areas - Recirculation | |
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| Factors Determining the Degree of Recirculation | |
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| Over-Pitching | |
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| Forward Flight | |
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| Three Basic Aspects of Horizontal Flight | |
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| Tilting the Disc with Cyclic | |
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| An Alternate Explanation of Cyclic Action | |
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| Dissymmetry of Lift | |
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| Eliminating Dissymmetry of Lift | |
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| Blow-Back (Flap Back) | |
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| Blow-back (Flap-Back) When Using Collective | |
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| Summary | |
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| Designs that Reduce Flapping Amplitude | |
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| Delta-3 Hinges | |
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| Offset Pitch Horns | |
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| Reverse Flow | |
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| Translational Lift | |
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| Transverse Flow Effect | |
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| Power, Range and Endurance | |
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| Power | |
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| Ancillary Power | |
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| Profile Power | |
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| Induced Power | |
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| Parasite Power | |
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| The Total Horsepower Required Curve (the HPR) | |
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| Attitude | |
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| Weight | |
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| Slingload and Parasite Drag Items | |
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| Flying the Helicopter for Range | |
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| Effect of the Wind | |
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| Engine Considerations | |
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| Range Summary | |
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| Flying the Helicopter for Endurance | |
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| Endurance Summary | |
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| Climbing and Descending | |
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| Climbing | |
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| The Horsepower Available Curve (The HPA) | |
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| Factors Affecting the Horsepower Available Curve | |
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| Altitude | |
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| Density Altitude | |
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| Leaning the Mixture | |
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| Collective Setting | |
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| Rate of Climb | |
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| Angle of Climb | |
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| Effect of Lowering Horsepower Available Curve | |
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| Summary | |
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| Effect of the Wind | |
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| Climb Performance Summary | |
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| Descending | |
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| Angle of Descent | |
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| Effect of the Wind on Descents | |
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| Descent Performance Summary | |
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| Maneuvers | |
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| Turning | |
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| Rate of Turn | |
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| Radius of Turn | |
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| Rate and Radius Interaction | |
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| The Steep Turn | |
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| Power Requirement | |
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| The Climbing Turn | |
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| The Descending Turn | |
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| Effect of Altitude on Rate of Turn and Radius of Turn | |
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| Effect of Changes in Gross Weight on Rate and Radius | |
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| Effect of the Wind on Rate and Radius | |
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| Effect of the Wind on Indicated Airspeed and Translational Lift | |
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| Effect of Slingloads | |
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| Effect of Slipping and Skidding | |
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| Pull-Out from a Descent | |
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| The Flare | |
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| Initial Action | |
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| Flare Effects | |
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| Thrust Reversal | |
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| Increasing Total Rotor Thrust | |
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| Increasing Rotor rpm | |
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| Management of Collective | |
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| Retreating Blade Stall | |
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| Effect of Increasing Airspeed on Stall Angle | |
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| Factors Affecting the Advancing Blade | |
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| Symptoms of Retreating Blade Stall | |
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| Recovery | |
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| Factors Influencing V[subscript ne] | |
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| Conclusion | |
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| Autorotation | |
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| Initial Aircraft Reaction | |
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| The Lift/Drag Ratio and Forces Involved | |
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| The Stalled Region | |
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| The Driven (Propeller) Region | |
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| The Driving (Autorotative) Region | |
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| Combined Effects of All Regions | |
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| Autorotation and Airspeed | |
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| Combined Effect | |
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| Effect of Forward Speed on the Three Regions | |
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| Effect of Airspeed Changes on Rotor rpm | |
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| Autorotation Range and Endurance | |
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| Effect of Altitude on Range and Endurance | |
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| Effect of Gross Weight on Range and Endurance | |
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| Effect of Parasite Drag and Slingloads on Range and Endurance | |
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| Touchdown | |
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| Loss of Power at Low Heights | |
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| Factors Influencing Rotor rpm Decay When the Engine Fails | |
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| Combination of Airspeed and Height Best Avoided | |
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| Hazardous Flight Conditions | |
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| Vortex Ring State | |
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| Effect on the Root Section of the Blade | |
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| Effect on the Tip Section of the Blade | |
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| Flight Conditions Likely to Lead to Vortex Ring State | |
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| Symptoms of Vortex Ring State | |
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| Recovery from Vortex Ring State | |
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| Tail Rotor Vortex Ring State | |
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| Ground Resonance | |
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| Causes of Ground Resonance | |
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| Factors that May Cause Ground Resonance | |
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| Rotor Head Vibrations | |
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| Fuselage Factors | |
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| Ground Resonance Recovery Action | |
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| Blade Sailing | |
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| Dynamic Rollover | |
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| Factors Influencing the Critical Angle | |
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| Cyclic Limitations | |
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| Mast Bumping | |
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| Avoiding Mast Bumping | |
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| Recovery from Low and Zero g | |
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| Mast Bumping Summary | |
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| Exceeding Rotor rpm Limits | |
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| Reasons for High Rotor rpm Limits | |
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| Engine Considerations | |
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| Blade Attachment Stress | |
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| Sonic Problems | |
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| Reasons for Low Rotor rpm Limits | |
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| Insufficient Centrifugal Force | |
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| Reduced Tail Rotor Thrust | |
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| Rotor Stalls | |
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| Recovery from Low Rotor rpm | |
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| Helicopter Design and Components | |
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| Transmission | |
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| Main Rotor Gear Box | |
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| Freewheeling Unit | |
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| Drive Shafts | |
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| Tail Rotor Gear Box | |
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| Rotor Brake | |
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| Clutch | |
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| Chip Detectors | |
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| Governors | |
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| Swashplate (Control Orbit) | |
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| Phase Lag | |
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| Advance Angle | |
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| Rotor Blades | |
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| Chordwise Blade Balancing | |
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| Spanwise Blade Balancing | |
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| Trim Controls | |
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| Bias Control | |
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| Electronic Servo Systems | |
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| Tail Rotors | |
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| Tail Rotor Flapping | |
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| Tail Rotor Rotation | |
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| Helicopter Vibrations | |
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| Types of Vibrations | |
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| Vertical Vibrations | |
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| Lateral Vibrations | |
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| Combined Vertical and Lateral Vibrations | |
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| High Frequency Vibrations | |
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| Engine Vibrations | |
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| Remedial Action by the Pilot | |
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| Control Functions | |
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| Collective | |
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| Twist Grip Throttle | |
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| Engine Cooling | |
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| Carburetor Icing | |
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| Dual Tachometer Instruments | |
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| Rotor Stabilizing Design Systems | |
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| The Bell Stabilizing Bar | |
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| The Hiller System | |
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| The Underslung Rotor System | |
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| Rotorless Anti-Torque System | |
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| Advantages of the Notar System | |
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| Components | |
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| Air Intake | |
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| Engine-driven Fan | |
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| Slots | |
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| Direct Jet Thruster | |
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| Vertical Stabilizers | |
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| Undercarriages | |
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| Skids | |
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| Wheels | |
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| Oleo (Shock) Struts | |
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| Stability | |
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| Static Stability | |
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| Dynamic Stability | |
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| Stability in the Three Planes of Movement | |
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| Longitudinal Stability | |
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| Longitudinal Stability Aids | |
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| Lateral Stability | |
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| Directional Stability | |
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| Directional Stability Aids | |
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| Cross Coupling with Lateral Stability | |
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| Offset Flapping Hinges | |
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| Special Helicopter Techniques | |
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| Crosswind Factors | |
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| Lateral Blow-back (Flap-back) | |
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| Weathervane Action | |
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| Effect on tail Rotor Thrust | |
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| Different Types of Takeoffs and Landings | |
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| Downwind Takeoffs and Landings | |
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| Running Takeoff | |
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| Cushion-Creep Takeoff | |
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| Confined Area Takeoff (Towering Takeoff) | |
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| Maximum Performance Takeoff | |
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| Running Landing | |
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| The Zero-Speed Landing | |
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| Operations on Sloping Surfaces | |
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| Sling Operations | |
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| The Equipment | |
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| The Sling | |
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| Ground Handling | |
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| Flying Techniques | |
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| Snagging of Cable or Strap on the Undercarriage before Liftoff | |
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| Never-Exceed Speed (V[subscript ne]) | |
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| Preflight Rigging | |
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| Length of Cable or Strap | |
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| Number and Type of Slings | |
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| Nets | |
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| Pallets | |
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| Load Center of Gravity | |
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| Pilot Action in Case of Helicopter Oscillation | |
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| The Approach | |
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| Types of Slingload | |
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| Horizontal Loads | |
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| Unusual Loads | |
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| Conclusion | |
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| Mountain Flying | |
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| Updrafts and Downdrafts | |
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| Thermal Currents | |
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| Katabatic and Anabatic Winds | |
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| Mechanical Turbulence | |
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| Wind Strength | |
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| Size and Shape of Mountains | |
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| Stability or Instability of Air | |
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| Wind Direction Relative to Mountain Orientation | |
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| Summary | |
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| Valley Flying | |
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| Ridgeline Flying | |
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| The "Standard" Mountain Approach | |
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| General Coinments on Mountain Approaches | |
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| High Attitude Approach Considerations | |
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| Transition | |
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| Ground Effect Considerations on Mountain Sites | |
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| Determining Wind Change during Critical Phases | |
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| |
| Landing Site Selection | |
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| Surface of Sites | |
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| Flight in Areas Covered in Snow and Ice | |
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| |
| Survival Equipment | |
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| Helicopter Icing | |
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| Ice Accretion | |
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| Influence of Temperature and Drop Size | |
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| Water Content of Air | |
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| Kinetic Heating | |
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| Shape of Airfoils and Other Aircraft Components | |
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| Mechanical Flexion and Vibration | |
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| |
| Ice Formation on Blades at Different Temperatures | |
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| Electrical Anti-Icing | |
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| Consequences of Ice Accretion | |
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| Engine Intake Icing | |
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| Helicopter Performance | |
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| Helicopter Performance Factors | |
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| |
| Altitude | |
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| Pressure Altitude | |
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| Density Altitude | |
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| Combined Effect of Pressure and Density Altitude | |
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| Moisture Content of Air | |
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| Aircraft Gross Weight | |
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| External Stores | |
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| The Wind | |
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| |
| Power Check | |
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| Performance Graphs | |
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| Units of Measurement | |
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| |
| Hover Ceiling Graph | |
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| Takeoff Distance over a 50-Foot Obstacle | |
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| |
| Turbine Engine Power Check | |
| |
| |
| Maximum Gross Weight for Hovering | |
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| |
| Climb Performance | |
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| |
| Range | |
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| |
| Endurance | |
| |
| |
| |
| |
| |
| |
| Weight and Balance | |
| |
| |
| Definitions | |
| |
| |
| Weight | |
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| |
| Balance | |
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| |
| Beyond the Center of Gravity Limits | |
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| |
| Excessive Forward Center of Gravity | |
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| |
| Excessive Aft Center of Gravity | |
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| |
| Summary | |
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| |
| Calculating the Center of Gravity Position | |
| |
| |
| To Calculate the Longitudinal Center of Gravity Position | |
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| |
| To Calculate the Lateral Takeoff Center of Gravity Position | |
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| |
| Summary | |
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| |
| Effect of External Loads on Center of Gravity Position | |
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| Conclusion | |
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| |
| Sample Examination | |
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| Temperature Conversion | |
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| Altimeter Setting Conversion | |
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| Review and Examination Answers | |
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| Glossary | |
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| Index | |