Hummingbird Project - Hummingbird is a small research helicopter, at Stanford University's Aerospace Robotics Laboratory, which navigates using an integration of the Global Positioning System with computer vision.

National Rotorcraft Technology Center - In conjunction with other research divisions and schools at Penn State, the Rotorcraft Center is focused on advancement of rotorcraft research and education.

Low Speed Aerodynamics Research Group, University of Glasgow - Conducts wind tunnel research on topics including the aerodynamics of helicopter rotor blades. Includes facility descriptions, profiles of current projects, and some online data.

AAL - Adaptive Helicopter Rotors - Information on Solid State Rotor System (SSRS) and Flight Test Program (R/C).

How Helicopters Work - Photos and many brief videos in this narrative help to describe helicopter controls, capabilities and complexity.

Helicopter Aviation - This site deals with the aerodynamics of helicopters, instruction on how to fly helicopters, mechanical components, helicopter maneuvers, and more.

Swiss Helicopters by Markus Herzig - News and information about helicopters of Switzerland.

Helicopter Zone - Provides links to helicopter sites, animated helicopter GIFs, photographs, and downloads.

How Does a Helicopter Work? - Answers common questions about helicopters and how they work.

Boeing Sikorsky RAH-66 Stealth Comanche Helicopter - Information on the RAH-66 Stealth Comanche helicopter and the stealth technology used in it.