Welcome

Welcome to Spinning Wing. We aim to provide useful content about helicopters, tiltrotors, and wind turbines—machines with spinning wings. We are in the process of creating new articles. Feel free to let us know if you have any recommendations, comments or questions.

March 13, 2026. We added an article about Glauert's equation for rotor-induced velocity.

March 6, 2026. We added an article about helicopter brownout.

February 23, 2026. We included a new article about helicopter friend/foe indentification.

December 4, 2025. We added an article about vortex ring state.

November 1, 2025. We added an article about helicopter turn and slip indications.

Helicopters

Helicopter Abbreviations and Symbols

Helicopter Components

• Avionics
• Helicopter Anti-Torque Systems
• Helicopter Engines
• Helicopter Landing Gear
• Helicopter Main Rotor Swashplate
• Helicopter SAS and SCAS
• Helicopter Weapons
• Identify Friend or Foe
• Turn and Slip Indications
• Vertical Speed Indicators

Helicopter Flight Test

• Flight Test Data: Estimating Frequency and Damping
• Helicopter Flight Test Challenges
• Helicopter Pace Truck

Helicopter Flight, Control and Stability

• Brownout
• Collective Rigging for Autorotation
• Coordinated Turns
• Helicopter Adverse Yaw
• Helicopter Autorotation
• Helicopter Climbs
• Helicopter Control Forces
• Helicopter Controls
• Helicopter Forward Flight
• Helicopter Ground Resonance
• Helicopter Landing
• Helicopter Lateral Flight
• Helicopter Noise
• Helicopter Off-Axis Control Responses
• Helicopter Stability

Helicopter Forces and Moments

• Helicopter Vibrations

Helicopter Malfunctions

• Helicopter OEI Training
• Loss of Tail Rotor
• Rotor Brake Pressure in Flight
• Rotor Overspeed
• SCAS Hardover
• Tail Rotor Fixed Pitch

Helicopter modeling and simulation

• Helicopter Atmosphere Modeling
• Helicopter Linear Models

Helicopter Performance

• Helicopter Safety
• Important Helicopter Airspeeds

Helicopter Rotors

• Glauert's Induced Velocity Equation
• Helicopter Blade Modes
• Helicopter Flap Dynamics
• Helicopter Main Rotor Design
• Helicopter Retreating Blade Stall
• Helicopter Rotor Brake Start
• Helicopter Tail Rotor Design
• Helicopter Transverse Flow
• Loss of Tail Rotor Thrust and Critical Azimuth
• Momentum Theory for a Hovering Helicopter
• Rotor Track and Balance
• Three State Dynamic Wake
• Vortex Ring State

Military Helicopters

Other Rotorcraft

Calculators

Helicopter Models

High Speed VTOL

Ingenuity Mars Helicopter

Personal Air Vehicles

V-22 Controls

Wind Turbines

Direct Drive Wind Turbines

Wind Turbine Airfoil Design

Wind Turbine Components

Wind Turbine Prebend

Wind Turbine Startup Process