Autopilot

An autopilot is a special tool for planes.

It helps fly the plane on its own. This helps the pilot not get too tired.

Long flights can be very hard for people. The autopilot can even help a plane land. It can land in thick fog or bad weather. This works by using smart computer code. The computer looks at where the plane is. Then it moves the controls to stay on track. It is a great helper for pilots.

An autopilot is a system that helps fly an aircraft.

It does not replace the pilot. Instead, it helps the pilot focus on other tasks. This includes watching the weather or the plane's systems.

Early pilots had to pay attention every second. Long flights made them very tired. The first gyroscopic autopilot was made in 1912. A gyroscope is a tool that helps keep things steady. This tool let planes fly straight and level.

Today, most large planes must have an autopilot. They use computer software to guide the flight. The software reads where the plane is. It also uses an inertial guidance system. This system tracks the plane's position. Sometimes, the tools have small errors called drift. To fix this, planes use radio aids or GPS.

Some autopilots can even land the plane. This is called an Autoland. It helps when the weather is very foggy. The plane can even stay on the center of the runway.

An autopilot is a clever system used to control an aircraft's path.

It does not replace the human pilot. Instead, it assists them with the hard job of flying. This allows pilots to focus on bigger things like weather or on-board systems.

Many autopilots work with an autothrottle. This is a system that controls the power of the engines. Together, they help the plane stay on its proper course. This makes long flights much safer for everyone on board.

How does this system work? Modern autopilots use computer software to guide the flight. The software reads the plane's current position. It then tells the flight control system how to move.

Most large planes use an inertial guidance system to find their way. This system tracks the plane's attitude and position. Sometimes, these tools have small errors called drift. To fix this, the plane uses radio aids or GPS to find its true location. This keeps the path very accurate.

People have been working on this for a long time. The first gyroscopic autopilot was made by the Sperry Corporation in 1912. Lawrence Sperry showed it worked in Paris in 1914. He even flew with his hands away from the controls!

In 1930, a team tested a reliable autopilot for the U.S. Army Air Corps. This system kept a plane at the right height for three hours. Later, in 1947, a C-53 plane flew across the ocean using an autopilot. It even handled its own takeoff and landing.

There are different levels of control for these systems. Small planes might only use a single-axis autopilot. This only helps with the roll axis, which keeps the wings level.

Two-axis autopilots also control the pitch, or the up and down movement. Large planes usually use a three-axis autopilot. This adds control over the yaw axis, which is the side-to-side movement. Some systems are even special. An Autoland can land a plane during thick fog. It uses an Instrument Landing System to stay on the runway.

Autopilots are built to be very safe and reliable. Engineers often use something called design diversity. This means they have different teams write the software.

If one team makes a mistake, the other team might not. The Space Shuttle used five computers to stay safe. Four ran the same software, but a fifth one was different. This helped ensure the shuttle could always fly. These systems make the sky a much more predictable place to travel.

An autopilot is an advanced system used to control an aircraft's flight path.

It does not replace the human pilot. Instead, it assists them by handling repetitive tasks. This allows pilots to focus on broader operations like monitoring weather or on-board systems.

Autopilots often work with an autothrottle. This is a system that controls the power delivered by the engines. Together, they manage the aircraft's speed and trajectory.

Modern autopilots rely on complex computer software to guide the aircraft. The software reads the plane's current position and attitude. It then instructs the flight control system to make necessary adjustments.

Large aircraft typically use an inertial guidance system to track their movement. However, these systems can experience drift, which is a corruption of positional data. To fix this, the system uses digital signal processing, often a six-dimensional Kalman filter. This filter resolves disagreements across roll, pitch, yaw, altitude, latitude, and longitude. Pilots also use radio aids like GPS or DME to correct the aircraft's position.

Autopilots are categorized by how many axes they control. A single-axis autopilot only manages the roll axis. These are sometimes called "wing levellers" because they keep the wings level. A two-axis autopilot adds control over the pitch axis, which is the up and down movement. This allows for automatic flight guidance after takeoff. A three-axis autopilot adds control over the yaw axis, which is the side-to-side movement. Most modern complex aircraft use three-axis systems to manage all flight phases. These phases include taxi, takeoff, climb, cruise, descent, approach, and landing.

Some systems are designed for specific, difficult tasks. An Autoland is a system that can land a plane on a runway. It uses an Instrument Landing System (ILS) Cat IIIc approach. This is used when visibility is zero, such as during thick fog. The aircraft can often stop on its own during an Autoland. However, a pilot must disengage the autopilot to taxi to the gate. Another option is Control Wheel Steering (CWS). In CWS mode, the pilot uses the yoke or stick to provide inputs. The autopilot then holds that specific heading and attitude to provide stability.

The history of this technology began in the early 1900s. In 1912, the Sperry Corporation developed the first gyroscopic autopilot. It used a gyroscopic heading indicator and attitude indicator. These were connected to hydraulically operated elevators and rudders. In 1914, Lawrence Sperry demonstrated the system in Paris. He showed it worked by flying with his hands away from the controls. In 1930, a more compact version kept a U.S. Army Air Corps aircraft on course for three hours. By 1947, a C-53 aircraft completed a transatlantic flight using an autopilot for takeoff and landing.

Safety is the most important part of autopilot design. Engineers use redundancy to ensure the system keeps working if a part fails. For example, the Boeing 777 uses triplicated microprocessors. These are fabricated in a radiation-resistant process. Some systems also use design diversity to prevent software errors. This means different engineering teams write the software using different programming languages. The Space Shuttle used this method with five computers. Four ran identical software, while a fifth backup ran independent software. This reduced the chance of a shared mistake causing a failure.

Another important system is the stability augmentation system (SAS). Unlike a standard autopilot, an SAS does not maintain a specific altitude or path. Instead, it moves control surfaces to damp out unwanted motions. A common type is the yaw damper, which helps swept-wing aircraft. It uses sensors to detect the start of a "Dutch roll" instability. A computer then tells an actuator to move the rudder in the opposite direction. This stabilizes the aircraft about the yaw axis. Some aircraft, like the B-52, require both pitch and yaw SAS to remain stable.