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.

September 9, 2023. We added calculators for advance ratio and inflow ratio.

July 9, 2023. We are in the process of creating pages describing helicopter malfunctions.

May 28, 2023. We added a page describing prebend in wind turbine rotors.

May 12, 2022. We added a page describing the Ingenuity helicopter on Mars.

Helicopters

Flight Test Data: Estimating Frequency and Damping

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

Helicopter Flight, Control and Stability

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

Helicopter Forces and Moments

Helicopter Malfunctions

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

Helicopter modeling and simulation

• Helicopter Linear Models

Helicopter Performance

• Important Helicopter Airspeeds

Helicopter Rotors

• Helicopter Blade Modes
• Helicopter Flap Dynamics
• Helicopter Main Rotor Design
• Helicopter Retreating Blade Stall
• 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

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