Stopping An Airplane - The Three Types of Brakes Used To Stop An Airplane

The Extension of Flaps and Spoilers on the Wings of an Aircraft

 An airplane stops when a combination of a number of things take place in sequence and/or together. Generally, commercial planes have 3 systems to stop the aircraft, described below. The first system that helps in stopping the airplane is called flaps. Look at the image at right and see how flaps are extended. These are extended before 5-10 minutes of descending. The flaps helps the airplane to decelerate, thus reducing the speed before touchdown. Pilots can extend the flaps to any configuration to meet the demand of deceleration. The lower percentage of the flaps helps to give the plane a lift but as a certain percentage is crossed (normally 35 %), the drag starts to prevail over lift, causing the airplane to slow.

The Spoilers, also called air brakes, aileron or speed brakes is another system to slow down an airplane before the touchdown and just after landing. Spoilers apply a backward force on the airplane's wings, with the help of air to slow the airplane. If you've ever looked out at a wing just before landing, you have probably seen them but only certain spoilers are opened in the air while others are locked out. See how spoilers are pointing up on the wings, in the right image.

The Engine Cowling a part of it opens up and lets the excessive air flow out in the forward direction

 The second system of slowing down an airplane is called reverse thrusters, which comes in action right after the airplane wheels touch the ground. The purpose of reverse thrusters is to redirect engine thrust to help stop the airplane. Reverse thruster, as the word says, redirects the airflow to some other direction. See in the image, how the frame that surrounds the engine looks if it’s fallen apart. This forces the air that’s coming out of the engine to be pushed up and down, altering the engine thrust. This in turn slows the airplane significantly. You can see when the reverse thrusters are in action. They normally operate until the airplane is slowed down to a manageable speed. The noise at that time is somewhat intense for a few seconds. You can also see the water or dust droplets kicking out of the engine. The power of the engines is clearly heard and seen. This is an amazing experience. Because airplanes are getting bigger and heavier and just need more advanced braking technology, all of the newer airplanes have them.

The applying of Wheel brakes on an aircraft

  The third system in the process of slowing and stopping an airplane is wheel brakes. Wheel brakes are applied gradually once both the rear and front wheels have touched on the runway. Commercial airplanes have at the minimum, wheel brakes for stopping. If the wheel brakes were just used to stop the airplane, it would take a very long runway length and the stopping interval would be greater. Some airplanes have auto brakes and the pilot can set their intensity to low, medium or high. Auto brakes are also used during take off and applies braking automatically in the event the take off is aborted for some reason.

Source - Flight Simulation