Provides pictures and background from the first designs to current machines. Also offers dictionary and links to related resources.

Aviation history in the WWW: Index of aircraft by category and time period.

History of this helicopter cavalry troop from the Vietnam War era of helicopters.

Unique collection of helicopters along with volunteers working on the restoration of the aircraft.

Dedicated to acquiring, preserving and protecting the historical materials that chronicle the aviation careers of Igor Sikorsky, the companies he founded and the accomplishments of its employees.

This site traces the evolution of rotary wing aircraft back to Leonardo Da Vinci.