Gaetano A. Crocco of Italy patented an early cyclic pitch design in 1906. Crocco recognized that a way to change the pitch cyclically on the blades was needed if a helicopter was to work properly in forward flight.

During 1906, the brothers Louis and Jacques Bréguet began their helicopter experiments and meticulously tested airfoil shapes under the guidance of Professor Charles Richet. In 1907, they built the Bréguet-Richet Gyroplane No. 1, one of the first mechanical devices to actually hover. The gyroplane flew for one minute on August 24, 1907 (some sources say September 29, 1907) in what is generally accepted as the first vertical flight. A 45-horsepower (33.5-kilowatt) engine provided just enough power to achieve vertical flight. However, there was no means of control or stability, and it needed four men to steady it while it hovered about 2 feet (0.6 meters) off the ground. Without a control system, it was not a practical helicopter.

The first vertical flight machine in the United States seems to have been developed by Emile Berliner and John Newton Williams. Berliner designed what may have been the first production rotary aircraft engine, the 36-horsepower (27-kilowatt) Adams-Farwell engine. In 1908, Williams constructed a coaxial machine for Berliner using two of these engines. It reportedly lifted both Williams and the machine—a weight of 610 pounds (277 kilograms)—but was probably steadied from the ground. Williams later built another craft using a 40-horsepower (30-kilowatt) Curtiss engine. It hovered at around three feet (0.9 meter), again steadied from the ground. Berliner also was the first to propose the auxiliary vertically mounted tail rotor.

In 1912, the Russian Boris Yuriev built a 445-pound (202-kilogram) helicopter that had a modern-looking single rotor and smaller tail rotor and large diameter, high aspect ratio blades. The tail rotor was needed to counteract the torque generated by the main rotor but it added weight and like Sikorsky's helicopters, had an undersized engine. The machine never flew properly. But Yuriev was one of the first to use a tail rotor and also one of several pioneers to propose the concept of cyclic pitch for rotor control.

Around 1912, the Danish aviation pioneer Jacob Christian Ellehammer became interested in vertical flight. He designed a coaxial helicopter with counter-rotating rotors that were stacked vertically. Each rotor consisted of a large aluminium ring about 20 feet (six meters) in diameter with six five-foot (1.5-meter) blades attached to the outside edge of the rotors. A cyclic pitch mechanism was used to change the pitch of the rotating blades and for control. Ellehammer made several short hops in the craft.

Around 1919, Henry Berliner built a counter-rotating coaxial rotor machine that made brief uncontrolled hops to a height of about four feet (1.2 meters) while steadied from the ground. In 1922, he mounted two coaxial counter-rotating rotors on the wing tips of a Nieuport biplane fuselage. Sets of movable vanes—flat surfaces mounted under the rotors—provided some control. The craft reportedly could manoeuvre in all directions and obtained a speed of about 40 miles per hour (64 kilometres per hour). In June 1922, it hovered around 12 feet (3.3 meters) off the ground and was successfully demonstrated to the U.S. Army in 1924. The Berliner aircraft are considered the first rudimentary piloted helicopters developed in the United States.

During the late 1910s and early 1920s, Louis Brennan of England's Royal Aircraft Establishment worked on a helicopter with an exceptionally large two-bladed rotor. To deal with the problem of torque, Brennan used a single rotor and mounted propellers on the blades themselves. The use of servo-flaps or ailerons inboard of the propellers achieved control. He took several low-altitude flights, which ended in October 1925, when the machine crashed.

In the 1920s, the Marquis Raul Pateras Pescara, an Argentinean working in Europe, achieved one of the first successful applications of cyclic pitch. He was also the first to demonstrate that a helicopter with engine failure could still reach the ground safely by means of autorotation—the phenomenon that caused blades to turn even without power being applied to them that resulted from the flow of air as the craft moved through it. His coaxial helicopter had biplane-type rotors with a total of 20 lifting surfaces. In 1924, Pescara set a new world record by flying his craft almost one-half mile (0.8 kilometre) in 4 minutes and 11 seconds—a speed of about eight miles per hour (13 kilometres per hour)—at a height of six feet (1.8 meters).

It weighed 3,600 pounds (1,633 kilograms), and the x-shaped structure was more than 60 feet (18.3 meters) wide, with four huge fan-shaped rotors mounted at each corner. The pilot controlled individual collective pitch mechanisms for each rotor. De Bothezat flew the helicopter on its first flight at McCook Field near Dayton, Ohio, in October 1922. This flight lasted about a minute and a half as the craft rose six feet (1.8 meters), drifted with the wind, and landed some 500 feet (152 meters) away. Over the next two years, the helicopter made more than 100 test flights—some rising to 15 feet (4.6 meters) and one with three passengers clinging to the frame to demonstrate the machine's stability. The U.S. Army tested the machine and commented favourably on it. But the Army abandoned it because of its complexity and unreliability and because de Bothezat was difficult to work with.