Quadcopter

A quadcopter, also called a quadrocopter, or quadrotor is a type of helicopter or multicopter that has four rotors. These small flying machines are very interesting because they can move up, down, and in many directions easily.

Although quadrotor helicopters and convertiplanes have been tested for a long time, they were just curious ideas until modern unmanned aerial vehicle or drone technology arrived. The small size and low inertia of drones makes it easy to control their flight, which has made small quadrotors very useful for things like delivering packages or taking pictures from the air.

Design principles

Each rotor helps the quadcopter fly by lifting it up and moving it. Quadcopters usually have two rotors turning one way and two turning the other way. This helps control how the quadcopter moves up, down, and turns.

Unlike regular helicopters, quadcopters do not change the angle of their blades while spinning. In the early days, people thought quadcopters might help with flying straight up and down. Some designs from the 1920s and 1930s were among the first to try this, but they were hard to control.

When all four rotors spin at the same speed, one way and the other the opposite way, the quadcopter does not twist. This means it does not need a tail rotor like regular helicopters. Turning the quadcopter is done by changing how hard the rotors spin.

All quadcopters follow the same air rules as other flying machines with rotors.

The main parts of a quadcopter are its body, four rotors, and motors. The motors and propellers are placed the same distance apart for the best performance.

In some designs, each arm has two motors turning in opposite directions to make the quadcopter stronger and more stable but lighter.

Operations

Autonomous flight

A quadcopter can be programmed to fly on its own. This has led to fun experiments where many quadcopters work together. They use simple sensors to notice other drones nearby.

Records

Endurance

A battery-powered quadcopter once flew for 2 hours, 31 minutes, and 30 seconds. This record was set in 2016 by Ferdinand Kickinger from Germany. He used special batteries and made the quadcopter very light to help it stay in the air longer. Other ways to make quadcopters fly longer include using hydrogen fuel cells or hybrid gas-electric generators.

Speed

The fastest quadcopter ever flew at a speed of 657.59 km/h (408.61 mph). This record was set by Luke and Mike Bell in Cape Town, South Africa on December 11, 2025. To set the record, they measured the average speed of two 100-meter runs in opposite directions.

History

Pioneers

The first heavier-than-air aerodyne to take off straight up was a four-rotor helicopter made by Louis Breguet. It only flew short distances and stayed low. In 1908, it was said to have flown several times, but we don’t know much more.

Etienne Oehmichen tried different rotorcraft designs in the 1920s. One of his designs, the Oehmichen No. 2, had four two-blade rotors and eight propellers, all powered by one engine. This aircraft was stable and easy to control for its time, and it flew over a thousand test flights. By 1923 it could stay in the air for several minutes, and in 1924 it set the first distance record for helicopters by flying 360 meters.

Dr. George de Bothezat and Ivan Jerome made the de Bothezat helicopter, which had six-bladed rotors on an X-shaped frame. This helicopter flew for the first time in October 1922 and had about 100 flights after that. It reached a height of about 5 meters. Even though it showed the design could work, it had trouble with power and control.

Postwar era

The Convertawings Model A Quadrotor was planned to be the first of many big helicopters. It had two engines powering four rotors and could fly forward well starting in 1956. But there were no orders for it, so the project stopped. Convertawings wanted to make a larger model that could carry heavy loads far away.

The Gloster Crop Sprayer project in 1960 was an early idea for a quadcopter drone. It would use a small engine and carry crop spray. Operators with beacons would guide it to keep it on course. But the company decided not to build it, so it never left the drawing board.

The Curtiss-Wright VZ-7 from 1958 was a special aircraft for the U.S. Army. It could take off and land straight up by changing the power of its four fan rotors.

The Piasecki PA-97 was a plan from the 1980s to combine four helicopter bodies with an airship.

Recent developments

The Bell Boeing Quad TiltRotor idea mixes a quadcopter with a tilt rotor to make a large military transport.

Airbus is working on a battery-powered quadcopter to use as a city air taxi, which might fly on its own in the future.

Drones

In the early 2000s, the four-rotor design became popular for small unmanned aerial vehicles, or drones. This design is simple but reliable and easy to control. Research continues to make drones better so they can work together and explore new places.

Although small remote-controlled quadcopters were made in Japan in the early 1990s, the first one with a camera made in large numbers was created in 1999.

From about 2005 to 2010, better electronics made it possible to make cheap, light quadcopters with cameras. Their small size and quick turns let them fly both inside and outside.

For small drones, quadcopters are cheaper and safer than helicopters because they have fewer moving parts. Their small blades also do less damage if they hit something. Guards can be added around the blades to make them even safer. But as quadcopters get larger, they can become harder to control quickly compared to helicopters.

Because they are easy to build and control, quadcopters are popular projects for hobbyists.

Military use

Small drones began being used by Ukrainian and Russian forces during the conflict in Ukraine starting in 2022. They were first used to gather information from the air.

Main article: Drone warfare § Russian invasion of Ukraine