How to land a plane in an emergency? Meeting with the ground: how planes land Landing an autopilot or manual mode.

Surely, after all, it will be interesting for someone to find out some technical details of their flight from point A to point B. What is going on behind the closed front door in those minutes when half of the cabin is ready to forgive everyone and everyone any sins, become righteous and start losing weight from Monday?

By the way, passengers very often confuse this front door with the door to the toilet. Sometimes they try long and hard to open it, despite the fact that on the planes of my company the inscription warning that access is only for the crew is made in large red letters and is much more visible than in the photo below.

Photo by Marina Lystseva photographersha

To many ordinary people, a modern aircraft seems to be something akin to a starship - buttons, displays, levers. Therefore, it is not surprising that faith in the unlimitedness of design ideas often exceeds the real capabilities of modern aircraft.

Indeed, why not a spaceship?

And this despite the fact that the B737NG was developed twenty years ago and already looks rather archaic compared to the most modern models:

Photo of the Airbus A350 cockpit from the Internet

Photo by Marina Lystseva photographersha

Does this whole stray still need people? Moreover, in the amount of two?

Many really believe that the liner performs all landings automatically. That is, the pilot is needed there only to press the magic button "LANDING" or whatever its name is?

However, there are also skeptics who, in all seriousness, believe that the achievements of modern technical thought can not implement the landing algorithm without a person:

inspit
“You should not confuse automatic landing approach and landing itself, i.e. touching the concrete runway with the wheels of the landing gear. Fully automatic landing is possible only with the participation of ground-based hardware radio landing systems. currently not practiced.

So is it practiced or not? Who is right?

Practiced.

The ability to automatically land an aircraft is not something recently invented. This show has been around for decades. Many models that practically left the arena were perfectly able to do this 30 or more years ago.

However, contrary to popular belief, automatic landing is still not the main way to return the aircraft to the ground. Until now, the vast majority of landings are done the old fashioned way - by hand.

Most importantly, certain conditions are still needed for automatic landing. Modern equipment (I note - certified equipment) does not yet allow automatic landing on any runway anywhere in the world. Important - the automatic landing system is not autonomous, that is, it requires external equipment, which must be installed for a given runway or airfield.

The most common type of landing today is an ILS precision approach with heading and glide path guidance (that is, a final descent on the straight ahead of touchdown). They are formed by specially shaped beams emitted by ground-based antennas. Aircraft equipment recognizes these signals and determines the position of the aircraft relative to the central zone, i.e., the extended center line of the runway. Accordingly, someone (the pilot) or something (the autopilot) sees the deviation indication and does their best to always fly center.

Video of automatic landing - view of the main flight instrument. Below and to the right you can see "diamonds" (from 01:02) these are indicators of the position of the course and glide path relative to the aircraft. If they are in the center, then the liner flies perfectly.

Cross in the center of the device - director arrows, keeping them in the center, the pilot or autopilot provides the necessary turn rates or climb / descent angles in order to reach the desired flight path (not necessary during landing approach - they can provide path guidance for almost the entire flight )

As a matter of fact, keeping the aircraft on the desired trajectory, the aircraft, controlled by the autopilot, reaches a certain height measured relative to the ground (50-40 feet), after which the leveling maneuver (FLARE) begins according to a cunning algorithm and after that, at a height of about 27 feet the automatic assistant smoothly reduces the operating mode of the engines (the pilot can do the same), and soon the landing takes place.

The most modern aircraft can also provide an automatic run up to the stop of the aircraft - after all, landing is a simple matter, it is also necessary to stop this colossus in complete fog! Rumor has it that some planes are also trained to steer in zero visibility, if the airfield would allow. I don't know, haven't checked. My B737-800 can only automatically land and (if there is an appropriate option on a particular aircraft) complete the run after landing.

Answering the question that started this thread can modern airliners land completely on their own, without the participation of the pilot? This means if all the data was previously entered into the computer. Or pilots release mechanization), I will say "They can't."

The plane itself not will begin a descent and landing approach, will not release mechanization and landing gear. Theoretically, this is quite possible constructively, but today a person sitting in a pilot's seat solves these problems. Modern computers are not yet ready to make decisions for a person, because situations in each flight can be very different, and it is not yet possible to standardize the trajectories of all those thousands of aircraft flying in the skies. A person with decisions is doing better so far. Read more on this topic at the link at the very end of the post.

"So what's the catch, Denis Sergeevich, if you say that auto-landing was invented a long time ago and works great, why is it still not used in every flight?"

--==(o)==--

Alas, the system has many limitations. Let's start with the fact that not every airfield has an ILS system. This is a rather costly system that pays off in the presence of heavy traffic and frequent bad weather.

Also, even if HUDs are present, automatic landing may not be permitted due to other restrictions. For example, in the mountainous Ulan-Ude, we cannot perform an automatic landing, because the glide slope angle exceeds the tolerance for doing so. What can we say about Chambery, in which the glide path is much steeper, and the runway is only two kilometers!

That is, there are restrictions for automatic landing - according to the maximum and minimum angle of inclination of the glide path, as well as according to the value of the wind - mainly lateral and / or tailwind.

That is, oddly enough, if the weather is "horrible", then landing, like it or not, you have to do it in Chkalovsky style. Manually. And if the glide slope is also steep, as in Chambery, then flying is not so boring, as usual.

Besides

There may be good weather and normal glide paths, but the "curve" runway and automatic landing can be a big risk in terms of a rough landing - yet the aircraft is not yet trained to predict terrain changes ahead. Runways such as Norilsk (19), Tomsk (21), Rostov (22) are not very suitable for automatic landing due to the specific bend of the runway, and each such landing turns into a game with decoding.

On some runways, the profile seems to be fine, but due to some natural or technical phenomena, the glide path is unstable and the plane "walks". Accordingly, a stupid autopilot tries to walk along with deviations, but a smart person does not. An example is the Kyrgyz Osh.

Many manufacturers either explicitly specify or recommend landing only on runways certified for ILS CAT II/III approaches. In this case, there is some guarantee that the glide slope will not walk, and the runway is not a curve. Although even when landing on such runways and on any others in conditions where CAT II / III operations are not performed, i.e., the ILS operates according to CAT I, the same Mr. Boeing recommends that very attentive when performing automatic landings - because in good weather, airfield services are not required to ensure the "purity" of the beams, so interference is possible - both from the aircraft flying in front of you, and from ground objects, which may well be located in the area of the course and glide path beams.

Therefore, oddly enough, good weather is not yet a reason to feel relaxed, trusting the autopilot.

ILS Performance

ILS Performance Most ILS installations are subject to signal interference by either surface vehicles

or aircraft. To prevent this interference, ILS critical areas are established near each

localizer and glide slope antenna. In the United States, vehicle and aircraft

operations in these critical areas are restricted any time the weather is reported less

than 800 foot ceiling and/or visibility is less than 2 statute miles.

Flight inspections of ILS facilities do not necessarily include ILS beam

performance inside the runway threshold or along the runway unless the ILS is

used for Category II or III approaches. For this reason, the ILS beam quality may

vary and autolands performed from a Category I approach at these facilities should

be closely monitored.

flight crews must remember that the ILS critical areas are usually not protected

when the weather is above 800 foot ceiling and/or 2 statute miles visibility. As a

result, ILS beam bends may occur because of vehicle or aircraft interference.

Sudden and unexpected flight control movements may occur at a very low altitude

or during the landing and rollout when the autopilot attempts to follow the beam

possibility and guard the flight controls (control wheel, rudder pedals and thrust

levers) throughout automatic approaches and landings.

Be prepared to disengage the autopilot and manually land or go-around.

Again, it is not necessary to perform a HUD approach (even in manual mode), because usually the approach schemes are quite "sweeping". In good weather, a visual approach is often preferred - the pilot will not follow the entire scheme, but will choose a more optimal trajectory, a shorter one, which will save time, fuel, and unload the controller.

True, in Russia such visits are not very practiced for various reasons. In the West, especially in the USA - very, very often.

So, above we talked about the weak noise immunity of the HUD system, and therefore not every runway equipped with a HUD is capable of auto-landing. Is humanity running into insurmountable difficulties?

Of course not!

There is a gradual introduction of a new precision approach system based on dead reckoning by means of satellite navigation. For a more accurate calculation, a special station (LKKS) is installed in the airfield area, and, as a result, we get a very, very accurate position of the aircraft in space. And, accordingly, the trajectory calculated from this position does not depend on snowdrifts on the ground or cars crossing the landing course. In addition, one such corrective station makes it possible to cover several airfields (for example, one is enough for the Moscow air hub). It should be understood that maintaining the operability of this system is much less expensive than maintaining the ILS.

Several dozen LKKS have been installed in Russia, however, officially (since recently) it has been operating only in Tyumen. Our company became the first passenger company to perform such a run in this city.

And this situation with LKKS for several years. Don't ask me why - I myself am at a loss, because this is a very stupid situation.

True, in order to carry out such visits, the installation of special equipment on aircraft is required. Considering that this approach is still not very popular in Russia, operators are in no hurry to finalize their liners.

However, sooner or later, such systems will replace ILS from airports.

Will progress push pilots out of the cockpit?

Thank you for your attention!

Once the landing of the aircraft is learned on the simulator, the pilot proceeds to training on the real machine. Landing of the aircraft begins at the moment when the aircraft is at the starting point of the descent. In this case, a certain distance, speed and altitude must be maintained from the aircraft to the runway. The landing process requires maximum concentration from the pilot. The pilot directs the car to the start point of the runway, the nose of the aircraft is kept slightly lowered during the entire movement. Movement - strictly along the strip.

The first thing the pilot does at the very beginning of the movement to the runway is to extend the landing gear and flaps. All this is necessary, including in order to significantly reduce the speed of the aircraft. The multi-ton vehicle begins to move along the glide path - the trajectory along which the descent occurs. Using numerous instruments, the pilot constantly monitors the altitude, speed and rate of descent.

Especially important is the speed and rate of its decline. As you approach the ground, it should decrease. Do not allow too sharp a decrease in speed, as well as exceeding its level. At a three-hundred-meter height, the speed is approximately 300-340 km per hour, at a two-hundred-meter height, 200-240. The pilot can control the speed of the aircraft by applying gas, changing the angle of the flaps.

Bad weather landing

How does a plane land in strong winds? All basic actions of the pilot remain the same. However, landing an aircraft in cross or gusty winds is very difficult.

Directly near the ground, the position of the aircraft should become horizontal. In order for the touchdown to be soft, the aircraft must descend slowly, without a sharp drop in speed. Otherwise, it may hit the strip sharply. It is at this moment that bad weather in the form of wind, heavy snow can cause maximum problems for the pilot.

After touching the surface of the earth, the gas must be released. The flaps are retracted, with the help of the pedals the plane taxis to the parking lot.

Thus, the seemingly simple process of landing actually requires great piloting skills.

Once in the cockpit of an aircraft (this is not difficult to do in an aviation museum), most people sigh with admiration when they see a lot of buttons, toggle switches, sensors ... It seems that in order to control this colossus, you need to be a genius! But in fact, the profession of a pilot is science and experience, nothing more. Of course, in the 21st century, many processes are simplified thanks to autopilot. But a person in the cockpit is still needed. For example, for the correct landing of the aircraft.

At another 400 meters above ground level, the landing approach begins: the plane “aims” at the runway (hereinafter referred to as the GDP), releases the landing gear (that is, “wheels”), fender liner, flaps, and slows down. If for some reason it is not possible to sit down after this (for example, from the airport they signaled about obstacles on the runway, the signal lights did not turn on, there was a downpour on the ground with poor visibility), the iron bird will rise to the second circle.

There is a special “decision-making height”, after which you can’t change your mind and fly up, you just need to go down. For most aircraft, this is 60 m.

The plane starts to land after a long descent, when 25 meters remain before the GDP. However, if the vessel is light, it will begin to land even lower - 9 meters from the ground.

The entire landing procedure before touching the ground takes only 6 seconds:

leveling: vertical speed drops to zero;
keeping: the angle of "attack" increases;
parachuting: the aircraft is pulled by the force of gravity, the lift of the wing is reduced, but does not disappear completely, so that the touch with the ground is smooth;
landing: depending on the type of winged bird design, it touches the GDP either only with the front landing gear, or with the whole “kit” at once (the so-called three-point landing).

Sometimes one of these processes is skipped. Yes, a pilot can "skip" a hold or a flare - everything but the landing itself!

More "specialized" types of fit

If we are not talking about a large passenger “liner” and a long runway, but about a limited GDP - say, about the deck of an aircraft carrier where fighters land, special devices help the pilot when landing.

Brake cables are being pulled on the deck of the same aircraft carrier. The fighter docks with them with a special hook, and thanks to this, it quickly slows down and does not fly into the ocean with its shaky GDP. It is worth noting that such a landing is carried out with the take-off mode of the aircraft turned on - suddenly the cable will let you down or the hook will miss, the expensive car will simply soar into the sky.

As for ground runways, if they are too short, some planes drop a parachute there - it increases braking.

Landing is also forced

Sometimes a winged bird lands at an alternate airfield. But this is not a forced, but a planned landing.

Circumstances beyond his control can force a pilot to make an emergency landing - for example, a serious breakdown (such as engine failure), in which he must first of all think about the safety of passengers.

In the movies, such cases look spectacular (remember at least “The Adventures of Italians in Russia”), but it’s scary live. Although this is only in relation to passengers, it is very curious to hear about such events in the news. Consider, for example, the landing of the A320 on the Hudson River. The plane did not sink, but the passengers were forced to climb onto the wings and wait for the rescue boat there.

Needless to say, the pilot who landed in any non-flying conditions definitely deserves the title of super professional!

Why do passengers applaud?

The reasons are different. Often those who return to their homeland after a long absence, including for a number of economic or political reasons, clap. Also, people show joy from a successful landing in difficult weather conditions or in cases where there was some kind of technical malfunction on board.

It happens that passengers clap for no reason, even if the flight and landing were in normal mode. Noticed: those who fly frequently do not usually applaud. But passengers who go on vacation a couple of times a year prefer to “thank” the pilots.

According to flight attendants, passengers are more likely to applaud on international flights. Much less often - after landing in European cities, where flights are cheap and residents fly very often.

By the way, landing is not a guarantee that all the dangers are behind. In 2005, in Toronto, during the landing of an Air France plane with several hundred passengers, there was a severe thunderstorm and rain. The aircraft landed with difficulty Passengers tell of harrowing escape and people started clapping. But they quickly realized that this was premature: the plane drove off the runway into a ravine and caught fire. No one died, but among the victims were those passengers who applauded.

How do others feel about applause?

Pilots don't hear passengers clapping. Flight attendants can tell pilots that the landing was applauded. But this is not always perceived positively.

There are pilots What do airline pilots think of passengers who applaud after a landing? who are pleased or indifferent that they clap.

It doesn't matter much to me. Passengers are not air travel experts and cannot determine how well the landing was. But I will never refuse applause. It's always nice, even if sometimes undeserved.
Peter Wheeler, pilot from Australia

But many pilots are offended by applause. They consider themselves professionals of the highest category, and therefore landing is not something out of the ordinary, but an ordinary job that they always try to do flawlessly. It is insulting to a pilot when passengers think that flying in an airplane is a game of roulette.

Passengers themselves relate to the tradition of clapping in different ways. Somebody