What RPM does a helicopter blade spin at?

Helicopter blade rotation speeds depend on the specific helicopter model, blade design, and flight conditions, but they typically range from a few hundred revolutions per minute (RPM) to several thousand RPM. Here are approximate blade rotation speeds for some common types of helicopters:

1. Small, Single-Engine Helicopters (e.g., Robinson R44, Bell 206B): Blade rotation speeds usually range from around 400 to 600 RPM.

2. Medium-Sized Helicopters (e.g., Airbus H135, Bell 429): Blade rotation speeds typically fall between 500 and 800 RPM.

3. Large, Multi-Engine Helicopters (e.g., Sikorsky S-92, Boeing CH-47 Chinook): These helicopters often have blade rotation speeds ranging from 700 to 1000 RPM or even higher.

4. Attack Helicopters (e.g., Boeing AH-64 Apache, Eurocopter Tiger): Blade rotation speeds for attack helicopters may reach up to 1200 RPM or more to optimize flight performance and maneuverability.

It's important to note that these are just general ranges, and specific helicopter models may have different blade rotation speeds depending on their design, operational requirements, and flight conditions.