How does the plane slow down when landing? Types of aircraft and methods of braking

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

The field of aircraft engineering is of interest to many people, especially those who often fly airplanes. Knowledge of the structure of aircraft will not only make you more erudite, but also relieve many fears, for example, the fear of flying. This article will talk about how the plane slows down when landing and how to slow down on different aircraft.

How planes slow down

Not only cars have brakes. Airplanes are also equipped with them, because when landing they can develop quite high speed, and the runway has a limit. Therefore, whatever one may say, one cannot do without a brake. There are several types of braking, and all of them are used on different types of aircraft. How do planes slow down when landing?

• Reducing engine power. The pilot simply slows down and the plane gradually comes to a h alt without further assistance. But this method is only possible on a long runway.
• Changebalancing position.
• Braking by increasing drag. This is usually achieved with the help of spoilers that are put forward after the pilot's command.
• Reverse braking. The aircraft engine turns on the reverse thrust, which is directed against the movement of the aircraft.
• Using the brakes on the chassis. Like cars, they come in several types: shoe, disc and drum.
• A special parachute can also provide braking to the aircraft during landing.

Types of aircraft

In aviation, two types of aircraft can be distinguished: civil and military. They are very different in design, so they have different braking systems. Also, the method of braking depends on the weight of the aircraft. Among military aircraft, fighters, interceptors, and bombers can be distinguished. They are small in weight and size, so they are most often slowed down using a braking parachute, which allows you to quickly stop the aircraft. Additionally, they use brakes on the chassis. Passenger liners usually use brakes on the chassis, as well as reverse engine braking. What is it?

What is reverse thrust

Engine thrust reverser is rarely used on small aircraft: it is mainly used on passenger liners. By itself, the reverse is needed to direct the air stream in the direction of or against the movement of the aircraft. The reverse thrust of the engine just serves for braking and for emergency descent. Most often it is applied after the plane has landed andtouched the surface with the wheels. Sometimes reverse is also used for reverse, but extremely rarely. But there are also jet planes. How is a jet engine built? If to reverse in a conventional aircraft it is enough to close the damper so that the air goes in the other direction, then in jet engines there are special bucket doors that redirect the air flow.

Advantages and disadvantages of reverse

Reversing the thrust of an aircraft engine has its pros and cons. The advantages include the fact that it allows you to slow down the aircraft at a time when the brakes on the landing gear are not yet working. With it, you can not only slow down, but also move in the opposite direction. With the help of a reverse, if necessary, you can quickly turn to the desired track by turning it on only on one of the engines. This is where all the pluses end. The efficiency of reverse motor reverse is only 30%. Therefore, other methods of braking are also often used on passenger aircraft. Together with them, there is a guarantee that the plane will definitely stop: if not using one, then using another device. Yes, and the weight of the device is too large, which is why it is used only on large liners that can boast a good carrying capacity. The disadvantages of the reverse also include its behavior at low aircraft speeds. When it drops to 140 or less km / h, there is a high probability of raising various debris from the air, which can then get into the engines.

Howslow down passenger planes

In passenger aviation, only one aircraft braking system is rarely used during landing. During the flight, many emergency situations can happen and in order to safely land the device, pilots usually have several options for braking. What can we say about passenger liners, where the responsibility increases many times. And the large weight of the aircraft simply does not allow braking using only one method. What methods are used in civil aviation?

1. Brakes mounted on a wheeled chassis. During landing, the aircraft is still at a sufficiently high speed that the brakes on the undercarriage are never used as the only means of stopping. Yes, and you can use them only after the wheels have touched the runway, and in fact the speed of the aircraft must begin to reduce even before that. In addition, traction may deteriorate due to weather conditions such as wet or icy surfaces.
2. Reversing the engine usually complements the first braking method. Only aircraft with a variable pitch propeller can create a reverse. The pilot simply changes the position of the propeller and begins to “pull” it in the opposite direction. On jet aircraft, reverse reverse is activated by changing the position of special dampers.
3. An auxiliary method of braking on passenger airliners is the use of special spoilers that extend during landing. They create drag, which also helps dampenaircraft speed.

The problem of braking in modern aviation is quite serious. After all, aircraft have been developing tremendous speeds for a long time, and their mass is most often very impressive. Therefore, the engineers had to try hard before they figured out how not only to land, but also to stop the Boeing or Liner.

Emergency braking

In the modern world, it is not easy to do without international flights, which often take more than one hour. Despite all the progress of civilization, the number of people suffering from aerophobia is only growing. Statistics persuade us not to be afraid of flights, because the risk of getting into a fatal accident is much higher than that of a plane crash. But fears are rarely justified, so many continue to fly only after drinking a sedative. But fears can be reduced if you get to know better the structure of the aircraft and how everything in it is arranged in case of various unforeseen situations. If for some reason one or more of the braking systems of the aircraft failed, then there are additional emergency methods that help to stop the aircraft even in emergency situations.

For example, in the event of an emergency landing with damaged brakes, heated fuel oil is spilled on the runway, which helps to reduce speed. Small planes use a drag parachute, which is ejected after landing and allows you to stop it quite quickly. Another way of braking: braking while still in the air by reducing engine thrust and increasing drag. Usually,deceleration of the aircraft does not cause any problems during landing. And all the causes of serious air crashes lie mainly in the unfortunate combination of several circumstances.

Light aircraft

Aircraft of different categories can be quite different from each other in terms of technical characteristics and design. Therefore, it is not surprising that the braking systems on different models also differ. How is the aircraft and its braking system arranged? Most often, pilots brake using a hydraulic brake system. The weight of a light-engine aircraft rarely exceeds half a ton, so additional braking devices such as spoilers are rarely installed on them. Disc brakes are installed on the chassis itself, the design of which is identical to the design of the brakes on cars. When the brake is applied, the pads are pressed against the chassis and create a mechanical obstacle to its further rotation. The task of the pilot in this case is to organize such pressure so as not to damage the surface of the wheel, but at the same time reduce the speed of the aircraft. As a rule, this method of braking is quite enough to stop the aircraft. Some "maize" also have reverse braking, with which the pilot can also control the aircraft on the landing field. Small airfields rarely have towing vehicles, so this feature comes in handy.

Fighters

How do military aircraft slow down when landing? Fighters and other military aircraftbelong to a very special category of aircraft. They are lightweight and capable of high speeds. In general, the braking method of fighters is not much different from other aircraft. They also use spoilers and brakes. Most aircraft have jet engines that have reverse thrust capability, but this feature is rarely used. If you turn it on during the flight, then the plane can simply be torn to pieces. And after the decline as a whole, it is enough to use only disc brakes and a spoiler. For example, the US F / a-18 fighter uses a spoiler spoiler as one of the braking systems, which rises above the aircraft body during descent. Also, in many models, the wings have many moving parts that can change their position and reduce the speed of the aircraft.

But there is one way of braking, which is used for the most part only on military aircraft. The parachute-braking unit is usually used during the approach to the airstrip, at a speed of 180 to 400 km/h. This allows you to dramatically increase air resistance, causing the aircraft to slow down. If the parachute takes off at the beginning of the runway, when the speed is still too high, then there is a risk of an accident, so it is used after applying other braking methods.

Landing on the water

Landing an airplane on the water is considered one of the most favorable landing options in an emergency. With competent actions, water softens the blow and allowsprevent serious damage. In the history of aviation, repeated examples of water landings are known, as a result of which hundreds of people were saved. When landing on the water, the pilot usually performs the following actions:

• Flaps, landing gear and spoilers are removed as they will only interfere with landing.
• Engines slow down.
• 20 km/h overspeed on landing is possible, which means the speed of the aircraft is about 200 km/h when touching the ground.
• The nose of the aircraft should be slightly raised.
• When in contact with water, the aircraft must be positioned as level as possible so that the surface of contact with water is as large as possible.

Thus, when landing an aircraft on the water, the pilots do not apply either the brakes on the landing gear or the reverse. Braking is done by the natural resistance of the water.

Information for those who are afraid to fly

If you have read this article, but are still afraid of flying, then simple knowledge that lifts the veil of secrecy about flying on an airplane and its internal structure can help you.

• There are several jet engines in every passenger plane. Thus, even if one of them fails, you are guaranteed to fly to the nearest airport.
• The flight of each vessel is controlled by the dispatch service, which monitors not only the weather, but also the route of the board.
• Most people are afraid of the turbulence zone. The so-called "air pockets" cancause considerable panic among the passengers. But do not worry about the safety of the wings and other parts. They are made with the expectation of enormous loads. The wing of an airplane can bend a lot, but not break.
• All systems have duplicate programs, so the risk of error is minimized. There are fallbacks for the same braking system and this applies to all major parts of the aircraft.
• In most modern civilian airliners, the flight is carried out using an autopilot. If necessary, the control switches to manual mode, but you should not be afraid of the human factor - everything is automated to the limit.

Results

Landing the plane is the most difficult part of the flight, which implies a lot of responsibility. There is no single answer to the answer to how planes slow down when landing. The pilot needs to do a lot of actions, on which the softness of the landing will directly depend. Most often, to stop an aircraft, not one, but several aircraft braking systems are used, which are switched on sequentially one after another. First, the pilot reduces the engine speed, which allows you to reduce the speed by almost half. Therefore, the plane comes in for landing already at a speed of 200 km / h. Then the flaps are extended and brought to the stop. After that comes the turn of the brakes on the chassis, which serve as the main brake. If the runway is too short or some kind of emergency has occurred, then the reverse engine or parachute is connected (depending on the type of aircraft). The totality of these activitiesallows you to stop the aircraft even in adverse conditions.