Helicopters were invented over a long period of development with key milestones from the 19th century, but the first successful practical flight of a helicopter was on September 14, 1939, by Igor Sikorsky in the United States. Key points in helicopter invention history include:
- The word "helicopter" was coined in 1861 by Gustave de Ponton d'Amécourt, who demonstrated a small steam-powered model that did not lift off the ground.
- Early helicopter models were built and tested throughout the late 19th and early 20th centuries, including experiments by Paul Cornu in 1907, who achieved the first free flight with a pilot, though it was unstable.
- Igor Sikorsky designed the VS-300 helicopter, which achieved the first successful practical flight on September 14, 1939. This helicopter introduced the single main rotor and tail rotor design, which became the industry standard and foundation for modern helicopters.
Thus, while concepts and primitive models date back to the 19th century and early 20th century, the first practical and successful helicopter flight that led to the modern helicopter occurred in 1939.
