The Basics of Flight #4 (Autopilot)

     The Basics of Flight #4

                                               By: Nirek Deepak

        Hello and welcome back to The Basics of Flight! Today we will be talking about the Autopilot system on an aircraft! Lets get started!

         I am using Boeing terminology for autopilot. However, autopilot can be the same for Airbus.

                                                    What is autopilot?

         The Auto Flight Control System (AFCS) is an automated flight system that allows the pilots to take their hands off the yoke. This system, which can follow the flight plan, can stabilize speed and height as well as the location of the front of the aircraft (heading). Autopilot is mostly used on passenger aircrafts. 

                                                   How does autopilot work?

        The main components of the autopilot system are the Autopilot Flight Director System and the Auto Throttle System. The autopilot is controlled by the Mode Control Panel(MCP) and the Flight Management Computer(FMC).  By using the MCP and FMC, pilots can command the autopilot to climb,cruise or descent,follow specific waypoints or vectors and in some circumstances, land by itself. For more info on the FMC, visit The Basics of Flight #3.  The autopilot relies on a series of sensors all around the aircraft collecting data such as the airspeed and altitude. The information from the sensors are sent back to the computers in the cockpit to determine where the plane is and how it is doing. If the plane veers of course a little bit, autopilot will make adjustments to put the aircraft back to its initial position. The autopilot can control the ailerons,flaps,spoilers on the wings,elevator pitch and trim as well as the rudder.To learn more about flight controls, visit The Basics of Flight #1.  The autopilot doesn't actually fly the plane without supervision from the pilots. When the autopilot is Banking or following the route, the pilots are always monitoring the autopilot. 

 

         Autopilot will follow the route and ATC(Air Traffic Control) clearance as shown above.

                                                When is autopilot activated?

           The autopilot is only activated once the pilots reach FL280(28,000ft) due to vertical separation requirements. When it is time to land, pilots generally disengage the autopilot and manually land the aircraft but in certain types of weather like low visibility, autopilot can land the plane in accordance with the necessary commands. It's called an automatic landing system. If the aircraft is trying to land under difficult conditions if there is a fog that completely blocking the sight, the aircraft's landing is performed in accordance with certain safety parameters with the help of ILS (Instrument Landing System). In such cases, the autopilot, acting in sync with the aircraft's other systems, provides the landing under the control of the cockpit team.

             Thank you for joining me today in the Basics of Flight #4. Hope you learned about autopilot. If you didn't read the Basics of Flight #3,#2 and #1, make sure to check them out. Don't forget to comment below and share this with your family and friends and I'll see you next time!