What is the air height of 10 km. What is the percentage composition of air at high altitudes. How often do pilots have their knowledge tested?

Until recently, it was believed that heavier gases predominate in the atmosphere adjacent to the earth's surface, and lighter gases far from it.

Numerous studies conducted in recent years have not confirmed this assumption. It was also not confirmed by the analysis of air samples taken at an altitude of 70 kilometers with the help of special rockets.

The results of the analysis of these samples and other studies have shown that the composition of the air in the layers of the atmosphere remote from the earth remains almost unchanged and the percentage of oxygen in it is the same as at the earth's surface.

Since the barometric pressure of air decreases as it moves away from the earth, the pressure of each component of the air separately also decreases, that is, the partial pressure of oxygen, nitrogen and other gases that make up the air decreases.

The partial pressure of oxygen at an altitude of 10 kilometers is almost 4 times less than at the earth's surface, and is only 45 millimeters of mercury instead of 150 at sea level.

The rate of oxygen penetration to blood vessels by diffusion is determined not by its percentage in the air, but by partial pressure. That is why, despite the fact that the oxygen content in the air at high altitudes is 21 percent, the amount of oxygen becomes less and less as you move away from the earth, and breathing is difficult for people. At an altitude of about 5 thousand meters, where the partial pressure of oxygen drops to 105 millimeters of mercury, a person already has heaviness in the head, drowsiness, nausea, and sometimes loss of consciousness. This condition is characteristic of oxygen starvation, which is caused by a reduced oxygen content in the air compared to its usual content at sea level.

Reducing the partial pressure of oxygen to 50-70 millimeters of mercury causes death.

When flying at high altitude, the pilot puts on an oxygen mask.

This is why without the artificial addition of oxygen to the air that pilots inhale during high-altitude flights, it would be impossible to achieve the modern flight ceiling.

At an altitude of 4.5-5 thousand meters, pilots have to use breathing masks, in which a little oxygen is added to the inhaled air from a canister. As the flight altitude increases, the amount of oxygen added to the mask increases. This ensures normal breathing for the aircraft crew.

Divers also use oxygen for breathing when working underwater. In an atmosphere of asphyxiating gases, firefighters use oxygen masks, into which air from the environment does not enter at all.

The main consumers of oxygen in nature are the animal and plant world. But plants and animals consume oxygen only for breathing, while man uses it to satisfy his domestic needs and in industry.

Where to aim? Maggie crashed onto the stone floor of the station, but his fall was halted when he crashed through the glass roof a moment before. It hurts, but it saves. A haystack would do too. Some lucky ones remained alive, having landed in a dense bush. The thicket is also not bad, although you can run into some branch. Snow? Just perfect. Swamp? A soft, vegetated bog is the most desirable option. Hamilton talks about the case when a skydiver with a parachute that did not open landed directly on high-voltage wires. The wires spring back and throw him up, saving his life. The most dangerous surface is water. Like concrete, it is practically incompressible. The result of falling on the ocean surface will be about the same as on the sidewalk. The only difference is that asphalt, alas! — will not open beneath you to forever devour the broken body.

Without losing sight of the intended goal, take care of the position of your body. To slow down your fall, act like a skydiver on a high jump. Spread your legs and arms wider, throw your head back, straighten your shoulders, and you yourself will turn your chest to the ground. Your frontal resistance will immediately increase, and there will be room for maneuver. The main thing is not to relax. In your, frankly, predicament, the question of how to prepare for a meeting with the earth, unfortunately, remains not completely resolved. An article on this subject was published in the journal War Medicine in 1942. It said: "In an attempt to avoid injuries, the distribution of loads and their compensation plays a large role." Hence the recommendation - you need to fall flat. On the other hand, a 1963 report published by the Federal Aviation Administration (FAA) states that the classic grouping adopted among skydivers will be optimal for saving life: legs together, knees higher, shins pressed to the hips. The same source notes that disaster survival is greatly facilitated by training in sports such as wrestling or acrobatics. When falling on hard surfaces, it would be especially useful to have some skills in martial arts.

Japanese skydiver Yasuhiro Kubo trains like this: he throws his parachute out of the plane, and then jumps out himself. Dragging the process to the limit, he catches up with his equipment, puts it on and then pulls the ring. In 2000, Kubo jumped at a height of 3 km and spent 50 seconds in free fall until he caught up with the satchel with his parachute. All these useful skills can be practiced in safer environments, such as free fall simulators - vertical wind tunnels. However, simulators will not allow you to work out the most crucial stage - a meeting with the ground.

If the water surface is waiting for you below, get ready for quick and decisive action. According to the surviving lovers of jumping from high bridges, we can conclude that the optimal entry into the water would be a “soldier”, that is, feet first. Then you will have at least some chance to get to the surface alive.

On the other hand, famous cliff divers who hone their skills near Acapulco believe that it is better to enter the water head first. At the same time, they put their hands with interlaced fingers in front of their heads, protecting it from a blow. You can choose any of these positions, but try to maintain a parachuting position until the very last second. Then, above the water itself, if you prefer to dive "soldier", we strongly recommend that you strain your buttocks with all your might. It would not be too decent to explain why, but you can probably guess for yourself.

Whatever surface awaits you below, in any case, do not land on your head. Researchers from the Institute for Road Safety concluded that in such situations, the main cause of death is a traumatic brain injury. If you're still being carried head first, it's best to land on your face. This is safer than hitting the back of the head or the top of the skull.

07:02:19 Altitude 300 meters

If, having fallen out of the plane, you started reading this article, then by now you have reached just these lines. You already have the initial course, and now it's time to pull yourself together and focus on the task ahead of you. However, here is some additional information.

Statistics show that in the event of a disaster, it is more profitable to be a crew member or a child, and if there is a choice, it is better to crash on a military aircraft. Over the past 40 years, at least 12 plane crashes have been recorded in which only one person survived. On that list, four were crew members and seven were passengers under the age of 18. Survivors include Mohammed el-Fateh Osman, a two-year-old child who survived a Boeing crash in Sudan in 2003, landing in the wreckage. Last June, when a Yemenia Airways liner crashed near the Comoros, only 14-year-old Bahia Bakari survived.

The survival of crew members can be associated with more reliable passive safety systems, but why children are more likely to survive is not yet clear. FAA studies note that children, especially those under the age of four, have more flexible bones, more relaxed muscles and a higher percentage of subcutaneous fat, which effectively protects internal organs. People of small stature - if their head does not stick out from behind the backs of aircraft seats - are well protected from flying debris. With a small body weight, the steady rate of fall will also be lower, and a smaller frontal section reduces the chance of running into a sharp object when landing.

07:02:25 Altitude 0 meters

So, we've arrived. Hit. Are you still alive? And what are your actions? If you escaped with minor injuries, you can stand up and smoke, as did the British Nicholas Alkemade, the tail gunner, who in 1944, after falling from a six-kilometer height, landed in a snowy thicket. If no jokes, then there is still a lot of trouble ahead of you.

Consider the case of Juliana Kopke. She flew a Lockheed Electra on Christmas Eve in 1971. The liner exploded somewhere over the Amazon. The 17-year-old German woman woke up the next morning under the jungle canopy. She was strapped into her seat, and there were piles of Christmas presents all around. Wounded, all alone, she forced herself not to think about her dead mother. Instead, she focused on the advice of her biologist father: "Lost in the jungle, you will go out to people, following the flow of water." Kopke walked along forest streams, which gradually merged into rivers. She avoided the crocodiles and pounded the shallow water with a stick to scare away the stingrays. Somewhere, having stumbled, she lost a shoe, only a torn miniskirt remained from her clothes. Of the food, she had only a bag of sweets with her, and she had to drink dark, dirty water. She ignored her broken collarbone and the inflamed open wounds.

Going on a trip by plane, leaving behind not the most comfortable moment of takeoff, the passenger finds himself in transcendental heights in a matter of minutes. When the sky is clear, through the window of the plane you can see pieces of the earth floating far below, in cloudy weather, the plane turns out to be above the clouds, which also float somewhere under it.

At what altitude do passenger planes fly? After takeoff, it is often announced that the aircraft is at an altitude of 10 km. An inquisitive person probably has a question - why are flights carried out at such an altitude, why is it better than others?

How high do planes fly?

10 km altitude is an average. As a rule, we are talking about a range within 9-12 kilometers, where the courses of aircraft that carry passengers are laid. And the pilot does not choose the height. The issue is resolved by the dispatcher, it is he who calculates the height for each individual flight. The pilot is obliged to listen to all the controller's instructions and follow them exactly. Otherwise, there is a risk of collision with other sides - this is extremely rare, but it happens.

: planes can climb to a height of more than 37 kilometers. But we are not talking about civilian aircraft, but about interceptor fighters. They have completely different technical indicators.

Altitude and air indicators

Height and pressure

It is known that at high altitude the air is rarefied. This is due to a simple circumstance. The planet's atmosphere is held together by its own gravity. This force manifests itself most powerfully near the surface, holding the air shell of the planet, providing it with maximum density precisely in the lower layers. The higher, the weaker the air pressure. Pressure increases closer to the surface from the weight of the upper layers of air, just as in the ocean pressure increases due to the upper layers of water. The aircraft and its flight performance are highly dependent on air performance, primarily on its density.

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Air is needed to provide lift, for the normal operation of engines. It is worth remembering that without oxygen, the combustion process does not occur, the engine stalls. If the density is small, this is bad, but too much is also not needed. Optimal conditions for civil aircraft are observed at an altitude of 10 km, in the air corridor from 9 to 12 km, depending on weather and other conditions.

Too much density is not needed for the reason that it does not allow the necessary speed to be developed. Dense air masses slow down the movement of the aircraft in the same way that water slows down the movement of a swimmer. Everyone noticed that in the water it is not possible to be as fast and agile as on land. This is due to the higher density of the aquatic environment compared to the air.

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A similar difference, not so pronounced for a person, but very noticeable for an aircraft that moves at a speed of several hundred kilometers per hour, is also observed between air masses at different heights. In addition to speed development problems, flying at low altitude brings high fuel costs, while flying in thinner air masses consumes less fuel. These are interconnected phenomena - to move in a denser space, more energy is required, and therefore more fuel.

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Optimal height

The air density within such limits remains sufficient to keep an aircraft flying at a specified speed in flight. At higher altitudes, more significant speed is required. So, when flying at an altitude of 12-15 km, a civil aircraft could only move at supersonic speeds, otherwise the air masses would not be able to keep it on the fly.

Modern design characteristics of civil aircraft make this height optimal for them. However, they may well fly at other heights, if necessary, slightly higher or much lower. But this is irrational and can be dangerous. Pilots of civilian flights are responsible for the lives of hundreds of people on board, it makes no sense for them to take risks, it would be irresponsible. Therefore, they adhere to the limits set by him, and the controller seeks to navigate each of the aircraft in the safest and most rational way for him.

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Thus, an altitude of 10 km is optimal for civil aircraft due to the air density and other environmental factors associated with such altitudes. This is the most rational, economical, safe, comfortable altitude, within which the entire main path of the aircraft passes, excluding the moments of its takeoff and landing, or emergency situations associated with oncoming flights in the corridor, weather conditions, and other circumstances when pilots are forced to fly higher or below.

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• Why are there swallows before the rain...

In Egypt, on November 3, the decoding of the "black boxes" of the crashed Russian aircraft began. Local journalists, however, reported a day before that, judging by the information on the flight recorders, the crew of the liner did not request an emergency landing from air traffic controllers, and also that there was no external impact on the liner. Soon, the news was also disseminated that four minutes before the tragedy, “sounds uncharacteristic for a regular flight” allegedly appeared on board. Meanwhile, the Federal Air Transport Agency asks to refrain from any conclusions until the official results of the investigation are announced.

We discussed the situation on the air of Radio Komsomolskaya Pravda with the current navigator - Sergey Kudryashov.

“Before each flight, the plane tests itself”

- What is the probability that the crew, knowing about the malfunction of the aircraft, may refuse to fly? Will the crew get on a faulty plane?

The probability is zero. Crews who fly on civil aviation aircraft will never take on a responsibility that they do not need. This is the first. The second is the level of the modern state of technology, which is now operated by airlines. Airbus Industrie aircraft are equipped with multiple internal control of all systems. Including before each flight, the aircraft tests itself and issues a special listing - that is, it prints the state of the systems and indicates which of them and in what state.

Sergey Kudryashov - about the crash of the Russian plane

In addition, there are also remote warning systems. The plane itself warns the company that it is defective. Telemetric information is sent via the communication line to the airline itself. This is independent of the technical staff. And in accordance with this, everyone is already perfectly aware that the plane is in a non-flying condition. If there has been an external destruction of the structure on the ground, that is, some structural elements that are clearly visible have been torn off, this is monitored by the flight crew, which bypasses the aircraft and carefully monitors its condition. In addition, there are ground control systems. I mean human - mechanics bypass, look, refuel. Visual control is constantly carried out for the integrity of the aircraft structure.

A disabled aircraft cannot fly. In accordance with this, you also need to ask yourself the question, every pilot has a family, has children, you need to earn money, and not be a kamikaze in order to make violation after violation, try to fly on something that cannot fly in principle. I think this version should be excluded from consideration.

“Skills are hacked into the crew with an ax”

- How long does it take to inform dispatchers about a change in the situation?

The crew that flies on aircraft such as Airbus, Boeing, on our aircraft - on the IL-96, on others - these are people who have gone through a very, very serious school. Their skills are cut with an axe. In accordance with the need, they immediately issue those necessary actions that they can perform. If something has happened to the aircraft, the condition is first assessed - it is necessary to figure out what is happening. Some signal boards start flashing or messages appear on the display screens, multifunctional indicators that are in the cab. Or there are flashing warning signals. They need to be sorted out. Some time goes by. If we have decided that there is a problem on board, and the plane is flying normally, but we are analyzing the situation by signaling, then it is necessary to issue a voice message or radio message that we have a problem on board. Mayday - the so-called SOS. In order to even issue this command, you need to consciously press the buttons several times so that the command goes on the air and so that the ground services accept this command and prepare to save the aircraft. The next decision made is that we will land the plane at the nearest airfield under the control of air traffic control specialists who will lead us and direct our approach. A whole range of actions that need to be taken.

In this case, which happened, nothing was done. The plane immediately went into an uncontrolled fall. Now some experts say: he went into a tailspin. A corkscrew is an aerodynamic figure that is described by certain laws. In this case, this was not the case. There was an erratic fall, which resulted in the aircraft, already inverted, falling to the ground. And, consequently, such a catastrophic phenomenon occurred on board, which did not allow the crew to take a single action that the aircraft flight manual and actions in special conditions require them to do.

“There is a version that the explosive decompression of the aircraft took place”

- Apparently, they died instantly?

They either died instantly, or were in such conditions that they immediately had to fight for the survivability of the aircraft, save passengers, and act by all means available to them in order to prevent a catastrophic development of the situation.

- There was information that before the liner disappeared from the radar screens, sounds uncharacteristic for a regular flight appeared on the recording from the cockpit. What could it be?

Here you need to wait for the decoding of the voice recorder, which records all the sounds that occurred during radio communications, during negotiations inside the cabin, during negotiations between the cockpit and the passenger compartment. All sounds were recorded there. To talk about the fact that something appeared, something happened there ... You and I will not be able to assess exactly what happened in this situation.

Today, a version was published that experts admit that an explosive decompression of the aircraft took place. That is, practically the pressure that was in the cabin was completely equal to the atmospheric pressure at an altitude of 10 thousand meters.

When we fly with you, we have atmospheric pressure in the cockpit, which we are used to breathing, and at 10,000 meters there was an instant depressurization, which led to the fact that we immediately lost the pressure habitual for human life. This suggests that immediately, in some fractions of a second, this happened. And the entire staff that was on the plane, he was already immobilized, at least.

MORE OPINION

"People fantasize"

The news about "uncharacteristic sounds" on board on the air of Radio "Komsomolskaya Pravda" was also commented on by the former pilot, flight safety specialist Alexander Romanov. The expert believes that it is impossible to believe any information now - you need to wait for official statements.

Alexander Romanov - about stuffing in the media

I think this is completely false information. Because the first information was that the pilots reported the failure of the equipment. They also wrote that groans were heard from under the rubble. This is all some kind of another duck or stuffing. People fantasize sometimes, you know, - the specialist warned. - I don't think the boxes have been deciphered yet. Because the commission has not been finally formed, and without it they cannot open them.

We express our condolences to the families and friends of those killed in the plane crash.

VGTRK exclusive from the crash site: what you see causes chills. The wreckage of a Russian plane that crashed in Egypt is scattered over an area of ​​about 30 square kilometers, this was announced on the Rossiya24 TV channel.

03/11/2015

Investigators questioned the management and employees of the airport in the Egyptian resort of Sharm el-Sheikh. According to sources in Cairo, the crew, until the very moment they disappeared from the radar, carried on the usual negotiations with the controllers.

And only at the time of the alleged catastrophe in the cabin of the airliner sounded extraneous sounds that were not characteristic of a regular situation. Experts are studying the details of the largest plane crash and suggest what could have provoked a sudden crash of the liner.

The director of the airport, the head of the dispatch service, a number of managers, as well as ordinary employees, met with representatives of the Egyptian prosecutor's office. Law enforcement officers interrogated them about servicing the ill-fated flight 9268. However, none of the staff noticed anything unusual. The crew did not give distress signals, and until the last minute, until the A321 aircraft disappeared from the radar screens, they carried on ordinary negotiations with the air hub controllers.

“From the record it follows that the situation on board 4 minutes before the disappearance of the aircraft remained normal, the crew was in regular negotiations with the controllers, nothing indicated a malfunction on board,” the source said.

He also added that at the time of the disappearance of the Russian airliner from the screens, sounds are heard on the recording that are uncharacteristic of a regular flight. According to the available recording, something that led to the disaster arose suddenly, catching the pilots by surprise. It is worth adding that this information may be contradictory, since it did not come from official sources, and recently Egyptian representatives have repeatedly made speculative statements.

extraneous noise

The version related to “abnormal sounds” is being discussed by Yury Sytnik, a member of the commission under the President of the Russian Federation on the development of general aviation.

“If there were such sounds, it means that someone pressed a button, the radio somehow worked and some noises from the cockpit could be on the air. But you know, it is simply not necessary to believe the data that comes from Egypt until the end of the commission's work. The buttons are located on the steering wheel or on the control stick, so it is very easy to press, and if the pilot quickly grabbed the handle, then most likely he could mechanically press this button. Therefore, I immediately dismiss the version of the fire that developed every second, in stages. I tend most of all to this version: after all, something happened on board the aircraft, and I do not exclude the possibility - 20-30 percent, that it is in the control system, that the crew fought with the aircraft, because this aircraft jump from 10 thousand to 8, then back to 10 thousand, I am very embarrassed. An aircraft can break up in the air for several reasons. Firstly, this is an explosion, structural elements are destroyed, and secondly, this is an exorbitant overload, when some parts of the aircraft fall off, up to the tail, the destruction of the fuselage, so here to say what led ... after decoding we will already know for sure. But today all versions have narrowed down to 2-3. As for the Wall Street Journal report, according to which large pieces of the hull began to separate from the liner at an altitude of 4.5 km or even much lower - but this is confirmed by the Americans that it fell off the echelon, and then due to off-design overloads and a large speed began to fall apart. If there was an explosion, then a small force. He tore off a door or some kind of hatch, or a piece of the fuselage. Later, when the plane began to fall, the speed increased, and huge masses of air flew into this hole, which tore the plane apart. It could be this too. Or it could be simply due to the fact that it fell down, and then, from overload, it began to fall apart. It is impossible that there was something in the design of the aircraft that could cause such an explosion. Fuel tanks don't explode, they are blocked. The engine catches fire too, usually without an explosion. I can't remember a plane blowing up mid-air."

In addition, the Egyptian media, citing some sources in the A321 crash investigation commission, reported that a malfunction inside the liner caused damage to the starboard side of the aircraft before it hit the ground. However, they did not specify what caused the damage to the aircraft - intentional actions in the liner itself, or a technical malfunction. It also became known that an American satellite recorded a thermal flash in the area of ​​the crash of the liner belonging to the Kogalymavia airline. Probably, American journalists note, the cause of the outbreak could be an explosion on board the aircraft or the detonation of the fuel tank after the aircraft was destroyed.

Depressurization - instant death

Oleg Smirnov, President of the Civil Aviation Partner Foundation, considers it incomprehensible that the crew did not react to the emergency situation that occurred in the cabin.

“Why didn’t the ship’s commander find a fraction of a second to press the radio transmitter button and report that there are some deviations from the regular flight? And this is possible only in a situation where something extreme, explosive, fast and catastrophic has happened. This also includes dangerous weather events, they are already officially excluded, because weather forecasters announced good weather. The second is the instantaneous depressurization of the aircraft, which still remains among the versions under consideration. And the third reason is an external influence: either an explosion inside the aircraft, or an explosion outside. In the event of an instantaneous depressurization of an aircraft at an altitude of 10,000 meters, the instant death of all life on board occurs. It is instantaneous, because nitrogen boils in the blood, which turns into bubbles, and the entire circulatory system, including the brain, is instantly clogged. Information about the detected elements that are not related to the design of the liner should be investigated. There are no problems - a chemical, physical analysis is carried out, and all this will be established. In this regard, I want to recall the plane crash in Scotland. Remember when the huge plane crashed and everyone died. And nothing was known for a long time. And then, a year later, a chemical analysis and a careful examination of all the wreckage of the aircraft, each wreckage, were carried out. The queue reached one fragment, and there they discovered just the explosion of a certain microdevice. A small disturbance is enough, and the structure does not withstand. It is not designed for such loads. It is designed for 4 tons of pressure, well, a little more. And when there is an instantaneous pressure of 20-30 tons, the plane flies apart. Of course, it looks like a terrorist attack, because if this is an explosion, then someone brought this explosive device, and again, here are claims against the ground services of Sharm el-Sheikh airport, because if someone brought an explosive device on board , well, it's the aviation security system on the ground that doesn't work. The commission will figure everything out, all this will lead to the fact that we will know the truth firsthand. And the first mouth in this case is a “black box”.

Difference in time

At the same time, at the disposal of the LifeNews portal was information that the time of death of the passengers of the tragic flight varies. According to a source in the investigating authorities, the people on board died with a time difference of 5-7 minutes. However, the findings do not refute the fact that the situation could develop rapidly.

"Attack! This version of the plane's death now looks the most convincing, but it also requires difficult and cardinal decisions. Up to the start of a large-scale ground operation against terrorists,” writes Valery Solovey.

"Don't skimp on charters"

Blogger Lena Miro invites people to learn a lesson from what happened in Egypt:

What are the lessons to be learned from the tragedy? They are simple and obvious.

1) The service life of aircraft by Russian air carriers should not exceed 12 years. This period is considered by aircraft manufacturers to be the maximum before the overhaul of the liner.

2) All routine and scheduled work, inspections should be carried out only on the territory of Russia by an authorized department. In the event of an accident due to equipment failure, prison terms up to life should be given to those who examined and carried out maintenance of this board.

3) Vessels under 12 years old, but having been involved in air accidents, should not be used by Russian carriers.

4) The number of flights performed by one aircraft should not exceed 30 per month.

6) A unified base of aircraft operated by Russian air carriers should be open to passengers. On the back of each ticket sold by a Russian airline, the entire history of the aircraft on which the flight will be made must be printed - age, maintenance, owners, reasons for sales, accidents, flight hours, and so on.

7) The operation of carriers with a fleet of less than 50 aircraft should be prohibited.

8) To oblige the service that controls the air traffic of the liners of Russian carriers to control and prohibit flights over war zones. In the absence of such a ban - put in jail for up to life.

By fulfilling the above points, our state will ensure flight safety. It is finally obliged to do this - to remove from the market not only the collapsed Transaero, but also all the other shit carriers!

With new and serviceable aircraft, we will be able to take off, fly and land safely.

Until then, I beg you, don't fly on charters. Don't skimp on tickets. Only with proven and large airlines, only on regular flights and new aircraft will you be safe. Your life is more valuable than the saved several thousand rubles y".