What is turbulence in the sky. Airplane turbulence: what it is

This is scary. It is not comfortable. This causes coffee and tomato juice to spill onto your pants. This is called “turbulence”. And how dangerous is it really?

Once the plane I was flying got into a strong turbulence. This situation is a great way to feel like a tiny grain of sand, on which nothing depends. After that incident, I avoided planes like the plague for a year.

Fortunately, our flight ended safely. The same cannot be said about some other cases. Last February, a flight from Denver to Billings for four passengers and one flight attendant ended in intensive care. And in December, due to turbulence, 14 passengers of the Seoul-Dallas flight were injured, the plane made an emergency landing in Tokyo.

These are just three examples that I could recall offhand. What do experts think about the real danger of an aircraft hitting a turbulence zone? Are belts a 100% guarantee of our safety?

Can a plane lose control and crash due to turbulence?

In short, the answer is no. And don't roll your eyes looking for killer arguments against such a response. You've probably already heard that the plane is the safest means of transportation. This is despite the fact that ground vehicles, unlike airplanes, cannot fall by definition. It seems more reliable than moving in an iron pipe dangling 10 kilometers above the ground.

But, despite the very unpleasant subjective sensations, turbulence by itself will never cause the plane to fall to the ground. Pilot Patrick Smith at AskThePilot.com explained that even the most severe movements of air masses cannot flip a plane or tear it apart.

Turbulence can cause damage. But this happens very rarely. In this regard, the incident of 1966 is often cited, when strong turbulence tore a Boeing 707 near Mount Fuji, to which the pilot wanted to fly closer to get a better view of the Japanese landmark. Gusts of wind in that place reached 140 miles per hour, which killed everyone on board.

But since then, the engineers have done some serious work. Aircraft design has become more resistant to such loads. Modern passenger airliners are capable of taking off at an angle of 90 degrees to the horizon, so they are not afraid of any gusts of wind on Earth. The Dreamliner 787, for example, is equipped with special sensors to accurately predict the location of turbulence zones. However, a combination of adverse weather conditions and other factors (eg pilot error) can lead to a disaster.

Professor Robert Sherman of the National Center for Atmospheric Research (USA) says history has recorded a couple of cases where very strong gusts of air tore the engines from the wings. But even in these circumstances, the plane landed safely at the airfield.

If the turbulence is severe, pilots can make route adjustments or land elsewhere. But even according to this scenario, the situation develops very rarely. However, conditions may not be dire enough to harm the aircraft. Usually an emergency landing is made due to the fact that one of the passengers neglected the command “Fasten your seat belts” and now he needs urgent medical attention.

Are passengers often injured due to turbulence?

Official statistics are silent here. Of course, national aviation agencies collect relevant data from airlines. But, as a rule, they only report serious injuries.

Professor Sherman says that in the United States, turbulence injury is reported if a passenger dies within 30 days of an incident or has been confined to a hospital bed for more than 48 hours. In addition, bone fractures, severe hemorrhages, nerve and ligament ruptures, second or third degree burns affecting more than 5% of the body surface, or damage to internal organs are taken into account.

More “minor” injuries, if the patient spends no more than a day in the hospital, are not counted. Therefore, official statistics can give a grossly underestimated estimate.

According to a 2013 report by the US Federal Aviation Administration, 24 people were injured due to the plane hitting a turbulence zone. Of these, 13 were crew members. Most of the injuries are suffered by those who have not fastened their seatbelt. Therefore, two thirds of the victims are flight attendants.

How do pilots perceive an aircraft entering a turbulence zone?

They care about two things: the comfort of passengers and their own safety.

It should be borne in mind that in the air, pilots of different aircraft communicate with each other “in real time”. They report the observed phenomena in the atmosphere. If someone got into a “bumpiness”, then his neighbors in the sky will immediately know about it. Also, this information is transmitted to dispatchers on the ground.

Pilots can change their route slightly to avoid turbulence. But this results in additional costs of fuel and time. Therefore, some of them do not pay much attention to turbulence.

The situation becomes truly threatening in the case of the so-called clear sky turbulence. Sudden and powerful blows of air masses are like a bolt from the blue. They are the source of most of the injuries associated with turbulence. The pilots are unaware of the threat that awaits them.

Professor Sherman argues that clear sky turbulence occurs most often over mountainous areas.

Last year, five passengers on United Airlines Flight 1676 were injured in sudden, very violent air strikes. The plane abruptly went down, and unfastened passengers "soared" up from their seats, hitting their heads on the carry-on luggage compartments and breaking their bottom. One child jumped out of his chair and landed in a nearby seat.

Another incident involving an American Airlines flight from Seoul to Dallas was in the news. The plane made an emergency landing in Tokyo to send more than ten passengers injured by being caught in a winter storm to hospital. The turbulence was so intense that food and drink flew through the cabin like birds.

Such cases are very rare, but they have every chance of becoming a hit on YouTube, if one of the passengers has time to film what is happening on a smartphone camera.

Should I be afraid?

The short answer to this question is “no”. But if he did not reassure you, then know that the numbers are on the side of your safety.

Professor Sherman says the odds of a plane hitting a zone of severe turbulence is one in a million. The actual occurrence of such dangerous zones in the atmosphere is higher, but pilots are trying to bypass them.

But do not forget to follow the recommendations of the flight attendants. Fasten your belts when asked to do so, and try not to undo them unnecessarily. This way, you will remain unharmed even in the turbulence of clear skies.

Experts advise not to rush to unfasten and run to the toilet immediately after leaving the zone of turbulence or takeoff.

The safest position during the flight is to relax in the seat with a seat belt. Breathe deeply and evenly. Remember, turbulence is normal. Modern aircraft are very reliable. You are completely safe.

Many people do not like to use a vehicle such as an airplane. Everyone has their own opinion on this matter, but they are usually united by one thing. What? Fear, of course. It can arise for a variety of reasons. Some people are afraid of crashing, others hate getting into turbulence. In addition, many consider this method of transportation to be too expensive.

What is turbulence?

And yet there are people who love to fly. When they get into turbulence zones, as a rule, the question arises as to whether this is harmful. Enjoying the flight, feeling the adrenaline during takeoff or landing is one thing, but when the body shakes (and not always lightly and safely), various arguments and assumptions arise. So what exactly is turbulence and how does it affect human health?

Turbulence is often called "bumpiness" among the people. In simple words, these are various kinds of aircraft vibrations that arise as a result of upward and downward eddy currents of the wind. In addition, a small area of ​​turbulence can occur due to some. Typically, the aircraft can withstand such loads, and passengers may feel only a slight wiggle.

What is the danger of turbulence?

Each pilot takes care of his plane and passengers. Therefore, he tries to avoid the slightest danger. Thus, the pilot avoids the cloud zone. But there are times when the plane gets into such currents of air that are capable of throwing it at supercritical angles of attack. As a consequence, the entire vehicle can be compromised. That is why the pilot will never deliberately fly into thunderclouds. Such objects are clearly visible on the radar and warn of possible obstacles.

Thus, the turbulence zone is not a predictable phenomenon. It is caused by congestion and may sometimes not appear on the pilot's locator. As a result, no one is immune from this.

Safety first!

It is impossible to say for sure if turbulence is dangerous. It all depends on the air flow. It should be noted that before the start of the flight, each pilot undergoes special training. During it, he gets acquainted with the weather and chooses the best route.

But there are also situations when it is impossible to plan or predict a route. When you fly on a plane for more than eight hours, it is simply unrealistic to predict the change in the weather. Then you should rely only on the excellent skills and attentiveness of the pilot. In addition, special equipment can protect the plane from trouble, which will soften the turbulence.

Other causes of turbulence

Note that jet streams can become one of the possible reasons for the formation of a turbulence zone. Their essence lies in the fact that they can change very quickly and in different directions, that is, in horizontal or vertical directions. A feature of such currents is that they can stretch for several hundred thousand kilometers. Most often they can be found in the eastern United States.

Due to the heavy traffic in the sky, the aircraft can avoid a particular zone of turbulence. In other cases, the phenomenon can negatively affect the person and the vehicle as a whole. It is very important that passing planes maintain a certain distance between themselves. Firstly, this is necessary so that they do not collide, and secondly, it helps to reduce the risk of getting into the turbulence zone.

Many people believe that turbulence is a result of pilot error or lack of professionalism. This is a completely erroneous assumption! The aircraft very often moves on autopilot, and the main task of the commander is to observe the radars in the cockpit and other devices. This function is disabled in case of strong shaking, which occurs when entering the turbulence zone. Then the pilot controls the plane manually. And how hard the aircraft will shake depends only on itself. The greater the mass of the aircraft, the more noticeable the tremors will be.

In addition to the above reasons, there is another one. For example, while descending, an airplane may collide with a strong vortex, a gust of wind. But you shouldn't worry too much about this, since nowadays special standards and flight parameters have been developed during the turbulence period, which allow you to avoid troubles. If they do not help, then it is the responsibility of the pilot to land the plane at the nearest emergency airfield.

Whatever turbulence zones you encounter on the way for passengers, you should never panic prematurely. Yes, let's not deny that such a phenomenon should not be underestimated. At best, before the flight, each person needs to prepare a little by listening to the recommendations of professionals and reading the necessary literature.

But one question still interests all passengers: "What is the danger of turbulence?" Let's hasten to reassure all people who suffer from aerophobia: turbulence can be a little scary, but in 120 years of aviation history, not a single disaster has occurred that could or could be caused by turbulence. This is because pilots know perfectly well how to react and behave in such situations. And also today there are a lot of parameters, standards, techniques that help to avoid an unfavorable situation.

Turbulence: Danger or Fear?

There are a lot of reasons for the phenomenal phenomenon: swirling from the ends of the wings, uneven heating of the air, meeting of air masses with different temperatures, and much more. But these are only minor factors that can lead to bumpiness. Either way, avoiding it is much easier than getting into the epicenter of events. Rest assured, no pilot will direct his plane to a dangerous place! A slight shaking should not be perceived as a warning sign and a threat to safe flight. The harm of turbulence is just a myth that, given the development of advanced technologies, cannot harm a person.

It is very difficult to remain calm when you start to shake and swing in different directions. The terrible pictures from the crash sites, seen on the news, immediately appear in my memory.

The need to fasten seat belts is alarming. We will discuss the causes of the turbulence and whether the plane could crash due to it.

To answer the question of why this phenomenon is dangerous, it is important to understand what are the reasons for its occurrence. Turbulence is one of the complex properties of the atmosphere. The air constantly changes temperature, pressure, wind direction and speed. Because of this, its density changes. Passing through such a zone, the plane begins to vibrate.

It is believed that this happens while passing through the cloud, but this is absolutely not necessary. The shaking also occurs in a perfectly clear sky. Most often this happens at low altitudes, 500-600 meters, or in flight under the clouds.

The exceptions are cumulus clouds (from below they look like caps from piles of snow) and thunderstorms. There is always a strong shaking in them. A high wind speed is able to properly brake and rock the plane. Such clouds usually fly around, they are perfectly visible on the radar.

The pilots choose a safer route in advance, which they compose, taking into account the reports of weather forecasters. Errors are likely only during a long flight, when the weather forecast is inaccurate. Then the pilot will bypass the cloud itself, but there is a chance to get into the turbulence of the air along the edges of the thunderstorm front.

• Do not miss:

The causes of turbulence, its presence or absence, do not depend on the experience of the crew. During the voyage, the aircraft is controlled by an autopilot. Only with very strong shaking does the pilot take control in order to take the aircraft out of the danger zone. By the way, how passengers feel shaking depends on the aircraft itself. If it is small and light, then the wind hurls it harder. Large and heavy vehicles are more stable.

Can a plane crash due to turbulence?

Aircraft design always takes into account the fact that they can get into a zone of turbulence. Therefore, the structure can easily withstand winds of 30 m / s and even more. The body will remain intact, nothing will fall off and it will not fall.

According to statistics, over the past quarter of a century, not a single plane crash has occurred due to falling into a zone of turbulence. Although, theoretically, there is such a danger. Any design has a power limit. A gusty wind during landing or takeoff is capable of hitting the plane on the ground. True, there are special standards according to which the pilot will simply leave for an alternate airfield due to weather conditions, so as not to risk it.

Why turbulence is dangerous for passengers

But what is really dangerous about a strong "bumpiness" is the panic of passengers. The vestibular apparatus perceives small rolls and a decrease in height by a couple of meters, as the car turns around its axis and falls. Coupled with a lack of understanding of the reasons, this causes a person an attack of panic fear.

Strong shaking is mainly dangerous for passengers who neglect safety precautions during the flight. Before passing through the turbulence zone, they are always warned about the need to buckle up and not leave your seats. These rules must be strictly observed, otherwise you can seriously injure yourself on the front seats or fly down the aisle. Pay attention to the stewards, if they took their places, then shaking is expected. Better hide your phones and other gadgets, or they may fly away.

As you can see, fear has big eyes. By following the recommendations of the flight attendants, you will safely experience the slight discomfort that the bumpiness brings. We hope that now your flights will become more enjoyable for you.

The topic of turbulence inherently comes up with the mention of various flows of gases, liquids or plasma. Most of the motions of matter are turbulent.

So what is turbulence? Turbulence is the definition of disordered, non-linear motion. The concept of "turbulence" does not have a clear and unambiguous definition. In the general case, this is a vortex motion of flows caused by an increase in their speed.

When calculating aircraft of a different kind, a flow is considered turbulent with the value of the hydrodynamic Reynolds similarity criterion derived from the Novier-Stokes equation, more than 2320. Reynolds in his studies indicated the factors affecting the movement of fluid: the flow becomes turbulent with an increase in the linear velocity and flow density, diameter holes (tubes) and a decrease in the dynamic viscosity of matter.

An example of a turbulent flow is air flows, which are vortices of various sizes that occur when the wind direction changes abruptly: from vertical to horizontal and vice versa. Atmospheric turbulence leads to discontinuities in the wind, various vertical transport of steam, condensation nuclei and other particles of mass and shape, as well as energy in the form of heat from one layer of the atmosphere to another.

Turbulence in aviation

Turbulence is of particular importance during aircraft flight. Not everyone knows what turbulence in an airplane is. When vortices are superimposed on each other, aircraft are exposed to multidirectional winds, as a result of which the lift and angles of attack of the wings change. A similar situation overboard leads to shaking and vibration - the so-called "blank".

Distinguish between moderate and strong blank. At the first jolts, changes in flight altitude and rocking of the aircraft are not so significant, and pilots do not experience difficulty in controlling the aircraft.

A strong blank is a more serious situation, consisting in frequent rolls and yawing, accompanied by a deterioration in controllability and stability in flight, as well as distortion of the readings of on-board instruments. A similar phenomenon, if appropriate measures are not taken, can create stresses in parts and individual assemblies, leading to significant breakdowns and deformations of equipment and airborne illness among crew members and passengers.

When entering turbulence zones, passengers often feel anxious about whether the pilot will cope with the situation. However, the qualifications and skills of the pilot can only be useful in the case of a very strong blank. In other cases, the turbulence zone does not have a strong effect on the flight - it is performed on autopilot.

What are turbulence zones? As a rule, this is the space where the probability of getting into long-term turbulence reaches 100%.

Nowadays, almost any passenger can determine when and where the vessel will shake during the flight. This became possible as a result of the creation of turbulence maps, where quieter zones are marked with a lighter color and vice versa. The online turbulence map was created to reduce the anxiety of passengers and crew, and allows you to predict and prepare if the plane gets into turbulence.

Is turbulence dangerous for an airplane? Of course, such a phenomenon causes anxiety and fear, and, if possible, bypasses it. As a rule, the instability of the atmosphere is not dangerous for the aircraft itself, since its design provides for such overloads. Most often, in 30% of cases, flight attendants are injured who did not have time to fasten their seat belts.

The size of the aircraft plays an important role in the feeling of shaking during turbulence. The larger the aircraft, the less inconvenience is. Sooner or later, everyone asks the question of where on the plane the least shakes during turbulence? When choosing a place, one should be guided by the intensity of the shaking in the cabin: the strongest one is in the tail section.

Causes of turbulence

The following causes of turbulence are distinguished:

• thermal convection (due to uneven heating of the surface or when mixing cold and warm air with significant vertical temperature changes);
• due to the friction of moving air currents on a rough relief;
• due to the inhomogeneity of the nature of air flows in the direction and speed, wave movements on inversion and isothermal layers (there are alternating descending and ascending flows).

An example of thermal convection is the formation of cumulus clouds.

Before each flight, the crew and the pilot himself are familiarized with the weather reports for the near future in order to choose the safest route. Particular attention is paid to the presence of cumulus clouds.

Cumulus clouds are dense atmospheric formations, most often separately located, with a height of the lower boundary up to 1200 m and a length of up to several hundred meters. They are formed as a result of powerful vertical flows and have internal ascending flows up to 10-15 m / s.

From the point of view of flight safety, it is forbidden to enter such clouds, as well as to fly a ship under them. Cumulonimbus clouds are especially dangerous, as heavy precipitation and electrical discharges are formed in them due to the presence of water particles. Therefore, it is recommended to route the route at a distance of 10 km from thunderclouds at an altitude higher than 1 km above them. The flight is complicated not only by high turbulence in the aircraft, causing turbulence, but also by poor visibility - up to 45m.

The overlapping zones of updrafts and downdrafts can extend over thousands of kilometers. Most cases recorded Most cases were recorded on the eastern shores of the United States.

Clear air turbulence

The absence of any clouds in the sky does not mean that there will be no turbulence. Above 5000 m, so-called clear-air turbulence may occur. This phenomenon is typical for mountainous areas on the leeward side of the slope. When the air flows around the mountains, the air flow deviates from the rectilinear direction, deforms and forms zones of increased turbulence. The distribution of zones varies in height: in the lower and upper parts it is maximum, and in the middle it is minimum.

If it is impossible to change course of flight, aircraft must maintain a certain distance in strict order to avoid collision.

Can a plane crash due to turbulence? For all the time, due to the turbulence of the clear sky, there have been five major plane crashes. In the complete absence of clouds, an airplane flying from Tokyo to Hong Kong was destroyed. Experts found that unusually high turbulence near the slopes of Fuji was the cause of the death of all passengers on the flight and the crew.

Another example is the crash of an airliner landing at an Alaska airport. The version of the tragedy due to turbulence was not immediately considered, since it contradicted the forecasts of the hydrometeorological center. However, an outflow of Arctic masses was subsequently recorded, which served as the formation of an anomalous air wave and a zone of turbulence.

On May 1, 2017, all domestic news channels reported that a Boeing 737, which was flying from Moscow to Thailand, entered a clear sky turbulence zone. It was impossible to establish the fact of an approaching air hole and avoid a ship falling into it, since not a single device recorded it. As a result of a sharp jump of the Boeing 200 meters, the passengers received multiple injuries and fractures.

According to statistics, about 1000 cases of precedents related to the instability of the atmosphere in a clear sky arise on average per year. Basically, they lead to flight delays, which causes great material damage to the airlines-carriers.

Pilot actions when entering a turbulence zone

According to Captain Chesley Sullenberg, who landed a passenger plane on the Hudson, when entering a zone of turbulence in the cockpit, one of two decisions is made: go beyond instability by lowering the altitude, or go into cloudless space by gaining it.

In case the plane gets into turbulence, a set of rules and recommendations has been developed for the cockpit and crew. You need to run the following commands:

1. Set the autopilot to manual control.
2. Turn on the "Tighten Belts" command.
3. Adjust the speed to 340 km / h.
4. Avoid a sharp drop in altitude, aircraft roll of more than 10 °.

In conditions of impossibility of avoiding the zone of strong blank, the crew commander is obliged to return the aircraft to the original or the nearest aerodrome.

Thus, the phenomenon of turbulence in the sky for the aircraft does not pose a strong threat. Like imperfections on highways (bumps, stones), turbulence in the air only requires undue attention from the pilot-in-command.

Turbulence (from Latin turbulentus - violent, disorderly) is a physical phenomenon in which fractal and linear waves of various sizes spontaneously arise in the flow of a liquid or gas. In aviation, turbulence is all sorts of aircraft vibrations that occur as a result of upward and downward eddy currents of the wind.

The usual bumpiness that occurs when flying through some types of clouds is safe. The aircraft is designed to withstand the resulting overload, and passengers can only feel a slight wiggle. Severe turbulence, which sometimes occurs in the upper atmosphere, can lead to more pronounced shaking in the passenger compartment. Therefore, when turbulence is detected, pilots turn on the "fasten your seat belts" display and ask passengers to take their seats.

What causes turbulence?

There are a lot of reasons for the occurrence of turbulence: swirling from the ends of the wings, uneven heating of the air, meeting of air masses with different temperatures, and much more.

Dangerous air turbulence often occurs in thunderclouds. They are clearly visible on a special radar in the cockpit, and, if possible, fly over them. However, there are also eddies along the edges of the thunderstorm front, they are not visible on the radar. Therefore, it is not always possible to fly around the turbulence zone.

In a clear sky, bumpiness also occurs, but the plane cannot always change the flight level due to heavy traffic in the sky. There must be strict intervals between aircraft to avoid collisions.

Aircraft often collide with strong wind vortices when descending. For the crew, standards have been developed for flight parameters with turbulence, and if they go beyond the limits, the pilot is forced to leave for an alternate airfield.

Jet streams can be another cause of turbulence. These are currents, the speed of which changes sharply both in the horizontal and vertical directions. A feature of such currents is that they can stretch for several hundred thousand kilometers. Most often they can be found in the eastern United States.

It is a big misconception that turbulence depends on the skill and skill of the pilot. The plane is on autopilot, and only when there is a very strong shaking, when the pilot's reaction is needed, they begin to fly manually. The force with which the plane will shake depends more on its design. The larger and heavier it is, the less turbulence is felt.

Is turbulence dangerous?

Many people suffering from aerophobia are afraid of getting into a zone of turbulence. But experts reassure: for 120 years of aviation history, not a single catastrophe has occurred, the cause of which was or could be turbulence.

However, with severe turbulence, there is a risk of serious injury. There were cases when passengers were thrown out of their seats, they received bruises and fractures due to impacts on the corners of the cabin. Suitcases that can fall out of the luggage compartments above the seats are also dangerous. To avoid unfavorable situations, it is necessary to observe safety precautions and unquestioningly obey all commands of the flight attendants.