* The concept of the helicopter goes back hundreds of years, and at the dawn of powered flight at the start of the 20th century, aviation pioneers believed that rotary-wing aircraft were right around the corner. In fact, while fixed-wing aircraft were quickly refined and improved, it wasn't until the mid-1930s that the helicopter began to emerge as a practical flying machine. This document outlines the early history of the helicopter, with a particular focus on early Sikorsky helicopters.