glissade- “sliding”) is a vertical projection of the flight path of an aircraft along which it descends immediately before landing. As a result of flying along the glide path, the aircraft enters the landing zone on the runway.

In paragliding, the base glide path is the straight path immediately before landing.

Glide slope angle- the angle between the glide path plane and the horizontal plane. The glide slope angle is one of the important characteristics of an airfield runway. For modern civil airfields it is usually in the range of 2-4.5°. The glide slope angle may be affected by the presence of obstacles in the airfield area.

In the Soviet Union, the typical value of the glide path angle was 2°40′. The International Civil Aviation Organization recommends a glide slope angle of 3° (Annex 10 to the 1944 Chicago Convention, Volume 1, Recommendation 3.1.5.1.2.1).

see also

Sources

• Large encyclopedic dictionary: [A - Z] / Ch. ed. A. M. Prokhorov.- 1st ed. - M.: Great Russian Encyclopedia, 1991. - ISBN 5-85270-160-2; 2nd ed., revised. and additional- M.: Great Russian Encyclopedia; St. Petersburg : Norint, 1997. - P. 1408. - ISBN 5-7711-0004-8.

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An excerpt characterizing Glissade

Denisov wrinkled his face even more.
“Skveg,” he said, throwing away a wallet with several gold pieces. “G’ostov, count, my dear, how much is left there, and put the wallet under the pillow,” he said and went out to the sergeant.
Rostov took the money and, mechanically, putting aside and arranging old and new gold pieces in piles, began to count them.
- A! Telyanin! Zdog "ovo! They blew me away!" – Denisov’s voice was heard from another room.
- Who? At Bykov’s, at the rat’s?... I knew,” said another thin voice, and after that Lieutenant Telyanin, a small officer of the same squadron, entered the room.
Rostov threw his wallet under the pillow and shook the small, damp hand extended to him. Telyanin was transferred from the guard for something before the campaign. He behaved very well in the regiment; but they did not like him, and in particular Rostov could neither overcome nor hide his causeless disgust for this officer.
- Well, young cavalryman, how is my Grachik serving you? - he asked. (Grachik was a riding horse, a carriage, sold by Telyanin to Rostov.)
The lieutenant never looked into the eyes of the person he was talking to; his eyes constantly darted from one object to another.
- I saw you passed by today...
“It’s okay, he’s a good horse,” Rostov answered, despite the fact that this horse, which he bought for 700 rubles, was not worth even half of that price. “She started falling on the left front...,” he added. - The hoof is cracked! It's nothing. I will teach you, show you which rivet to put.

Flight practice on the Tu-154 Ershov Vasily Vasilievich

On the glide path.

On the glide path.

Experienced pilots know: all mistakes, all rough landings, all rollouts are based on one decisive factor - the inability to keep the runway on target.

The pilot's inability to keep the directional needle in the center all the time, neglect

the stability of the car’s movement along the course, all sorts of theories on “selecting” the course when using the director system, entering the course at the last stage - all this is a sign of a person’s lack of understanding of a simple truth. It is impossible to solve the main problem while constantly being distracted by an annoying little thing: “some” course.

It is impossible to ride a bicycle well if you constantly compare the side of your lean and the side and amount of deflection of the handlebars. Until you achieve a reflex.

This is the kind of reflex a pilot should have to the directional needle. The off-center position of the arrow should cause discomfort. The response to needle deviation should be automatic. A sense of target must be developed. Whoever has it, always strives exactly on the axis; he always sits on the axle, and landing off the axle makes the professional feel inferior.

If the pilot solves the problem of maintaining a course reflexively, then all his attention can be directed to analyzing the behavior of the machine along the longitudinal channel. Such a pilot has a better chance of solving this problem without errors.

The task of moving an aircraft along a glide path is to select such a thrust force that it is constantly equal to the drag force, which means that the speed is constant. When attached to an aircraft external forces the pilot must evaluate the effectiveness of their impact in terms of magnitude and time and either be able to wait out these disturbances, or - if they threaten to disrupt the balance of forces - change the flight parameters, returning to the original mode as soon as the disturbing forces disappear.

In practice, as we know, this is a continuous change in the pitch and thrust of the engines. And by the frequency of commands on the pre-landing straight, one can judge the professionalism of the pilot.

Most often, the pilot, through his inability to calculate the glide path conditions in advance, creates difficulties for himself. Figuratively speaking, he “flies behind the plane,” reacting to disturbances by changing the mode and pitching.

This driving style reminds me of an inexperienced driver driving along our Russian streets. I saw a hatch - I drove around, I saw a hatch - I drove around, I saw a hatch - I drove around... Why, stand in a different row or something. No, he reacts. Such control of an aircraft is still the same consumerism of movement, the same principle of “gas - brake”.

So, we have a task before us: constancy of instrument and vertical speeds. Their calculated values ​​are known: roughly, 270 and 4, respectively. How to analyze the behavior of a car on the glide path, “what to dance about”?

They “dance” from the vertical speed. If it is stable, then the approach is stable. If the vertical is stable up to the end, then the approach is ideal, the problem is solved, and all that remains is to land.

If the vertical speed, while maintaining the glide path needle in the center, begins to increase, it means that either a tailwind component has appeared, or a counterwind has fallen.

If such a phenomenon occurs after a PDRM, it is usually due to a weakening of the wind near the ground. If it is at altitude, then you should remember that a change was expected, perhaps a wind shift.

In any case, an increase in vertical speed entails an increase in translational speed. But - only on the condition that the glide path is in the center, which means that the plane is moving along the hypotenuse, and all the laws of vector addition apply. If the increase in vertical speed is associated with suction under the glide path, then the directional needle will vigorously go up at the same pitch and at the same speed.

If a mistake is made and the pitch is reduced, the plane will go under the glide path with an increase in both vertical and indicated speeds.

The pilot constantly analyzes the reason for the change in vertical speed. Either it’s his technical errors, pitch swing; either it is a change in the wind; or changes in temperature and air density, affecting the amount of thrust in the same mode and the amount of lift at the same forward speed. In the latter case, the increase in vertical is an inevitable consequence of the pilot reducing the pitch angle in order to keep the glide path needle centered.

Either the pilot maintains a high mode and accelerates the speed, but the plane strives to go above the glide path and in order to keep it on the glide path, it is necessary to increase the vertical speed.

Having determined the reason for the change in vertical speed, the pilot must evaluate whether it is possible to return to the original flight mode only by deflecting the control wheel, if this was his technical error, or whether it is necessary to change the engine thrust if flight conditions have changed with altitude, or wait until the disturbance disappears, and wait until the car, which is stable in speed, returns to its original mode.

In any of these cases, you must operate the elevator as carefully as possible. Usually, a sensitive pilot notices a tendency to change the vertical speed and strives to return it to the calculated value with a barely noticeable pitch impulse, immediately returning the control wheel to its original position. A click of the trimmer there is a click back. Actually, all piloting on the glide path, in addition to the automatically maintained course, is carried out precisely by maintaining the vertical speed. The director went up a little - the vertical immediately decreased. The director returned to the center - the calculated vertical line was immediately installed. If the director again and again strives to move upward, this is already a trend: it is necessary to reduce the vertical speed; what is the reason?

All this analysis is carried out on a subconscious level and is expressed in the brain only by the feeling of the desire of the aircraft, or rather the pilot himself: “I went higher. I'm being squeezed above the glide path... by a companion? Big mode? Inversion? Strong oncoming gust?

Depending on the establishment of the cause, I either simply press down, or I press and remove the mode, or I hold and patiently wait: this impulse will fall, this impulse will fall; let the speed increase, I will be patient, the speed will also drop...

You can, of course, not think about it. Keep the director in the center and react to changes in speed: increased - remove the mode, decreased - add.

If in this case the vertical speed and, usually, the pitch swings accompanying its jumps are not taken into account, then, with a formal course and glide path maintained, with a constant indicated speed, it is still quite possible in front of the end to have an unexpectedly high vertical speed, the correction of which is made by a correction in maintaining the glide path, and correcting the error in maintaining the glide path can develop with an already non-design vertical speed.

In the narrowing wedge of possible deviations, attention and subtlety of movements are no longer enough; If at the same time attention is diverted to maintaining the course, the likelihood of a serious mistake increases.

The whole point of the analysis is to keep the vertical speed at which the 80-ton aircraft approaches the ground constant. In order to extinguish it, simple steps are required. But if the vertical speed of the ground is unpredictable, then it is not possible to catch the moment when it is exactly calculated, and a relatively soft landing is a matter of chance.

These subtleties, of course, do not apply to simple flight conditions in which

Even an ordinary pilot is capable of maintaining the parameters.

We fly in any, and even very difficult, conditions, when the captain is required to have all his willpower, all his talent, all his ability to control the situation - and, especially, the ability for subtle analysis in conditions of acute time pressure. And the more the captain is accustomed to analyzing the situation, the more subtle his sense and intuition develops, which allows him to control the behavior of the machine on a subconscious level, and pay more attention to maintaining a calm, friendly atmosphere in the cockpit, in which the crew works relaxed and confident.

The specificity of our work is that we often have to fly in winter to northern airfields, where severe frost inversions are not uncommon. The layer where the air temperature begins to drop sharply towards the ground lies somewhere at altitudes of 200-150m, and at this temperature boundary there is often wind shear, accompanied by bumpiness and jumps in instrument speed.

I had to land in conditions of a surface polar front, with strong winds, at temperatures below -30°, and, not counting on a frosty inversion at all, I nevertheless found myself in conditions of transition from warmer layers to colder ones just at an altitude of 150 meters - with a full set of all the troubles that accompany an inversion. Our Flight Manual limits engine speed reduction on glide paths below 200 m in wind shear conditions. Based on my experience and the experience of senior colleagues, I come to the conclusion that these restrictions, 72% and 75%, for “B” and “M”, respectively, were introduced out of fear of a sharp loss of speed in conditions of downdrafts near a thundercloud. But it is unlikely that our aircraft has been tested in conditions of frosty inversions for such a long time as we have been flying it under these conditions.

The restriction on the “not lower than 75%” mode for the “M” vehicle puts the crew in difficult conditions in the frosty winter. Sometimes, in a light car in a calm state, the required mode even when entering the glide path is already 78-76%. When approaching the ground, the air becomes so dense that the 75% mode creates too much thrust, and the plane begins to accelerate. There is no restriction to reduce the speed; increasing vertical speed only adds acceleration. On limited runways, this leads to such an overflight that it is better to go around.

If it is vital for the crew to land in such conditions, they must be aware of what is more important – the number or the actual behavior of the vehicle. The number 75 is calculated for wind shear in summer heat and is quite realistic. In conditions of low temperatures it is on the border of absurdity.

The plane flies perfectly in such conditions even in modes less than 75%, right down to low throttle as required. Therefore, in order not to unbalance the balanced approach mode, it is necessary to set the mode that the conditions require. The only thing is that in modes close to the idle mode, you need to carefully monitor the speed trend and add a mode in time before leveling if you notice a tendency for it to fall.

In any case, landing in low temperature conditions requires a timely reduction in engine speed, and the closer to the ground, the more energetic it is. The point here is that the headwind usually decreases toward the ground, which means the ground speed increases, and a slight increase in the vertical speed is required. A typical mistake of young pilots after a flyover is to go above the glide path, precisely for this reason. And the car must be pressed, which means reducing the mode in time.

Trends must be anticipated. If the pilot, while correcting, say, an upward deviation from the glide path, removed the mode and presses the machine from above towards the glide path, then one must remember about the removed mode and add this mode in advance, before reaching the glide path, because on the glide path the vertical speed will be required less than that from which the car is now catching up with the glide path.

It is unlikely that a flight engineer should be required on a heavy aircraft

perform the functions of automatic traction. Without instruments at his disposal to show the deviation of the machine from the trajectory, the flight engineer will always lag in his response only to changes in speed.

I apply the same to the use of a very imperfect autothrottle. I haven’t used it since the Shilak disaster and don’t recommend it to others. He is not able to react to changes in speed by changing the mode within 1-2%; he not only does not participate in the analysis of the machine’s behavior, but, on the contrary, introduces dissonance and confuses the thinking pilot. But for consumers who avoid manholes on the road, please. With a rating of “3” he is an assistant.

About portions of the regime. The RLE provides too broad standards. I always use one percent. Of course, in a strong chatter (to be more precise, in a “pre-challenge”) you have to use large portions, but if possible, I still try to be patient and, among the speed surges, catch the main trend, anticipating it with the same one percent.

We must always remember that 1% of the regime means tons of traction. The range from 70 to 95% in flight includes thrust from 500 kg to 10 tons. Do the math for yourself. If I allow myself to periodically apply and immediately remove 5 tons of thrust on the glide path, I will never achieve straight, uniform motion.

The same applies to the course. Watching from the side how the young pilot turns the helm, how he, all in business, corrects non-existent deviations - I suggest that he give up control. Does it fly by itself? And it flies on its own if it’s streamed. By the way, this should become the rule for both young and experienced pilots. Quit, make sure: am I not too constrained? Am I holding down the steering wheel?

But the closer to the ground, the narrower the wedge, or rather, the cone of deviations, the clearer, smaller, more timely the movements should be, the sharper the reaction should be - and the more stable the plane should fly.

An approach using the OSP system on a heavy aircraft requires strict adherence to design parameters, which is only possible with coordinated work of the entire crew. There is no control over heading and glide path, but only an approximate direction and an approximate, with a margin, vertical speed. It’s good if there is control over deletion; It’s good if you use a simple direction finder. It is easier to maintain the course using self-propelled guns in the “ZK” mode. At the same time, you must always remember one feature of approaching drives. The exit angle should always be taken to be half as large as it seems; The exit time is also taken to be half as long as desired. You can't go wrong.

Having trained at one time on the piston Il-14, I had plenty of time to observe the OSP approaches of my fellow students, constantly being behind them in a spacious cabin, unlike the current ones. And here I realized that the pilot (and me too) has an inherent desire to get on course as quickly and sharply as possible. And I saw what comes out of these attempts. The plane has already entered the landing course and continues to follow with an exit angle already beyond the position line, and the ARC is still late and cannot convincingly show that you are already on the other side. And when it shows, you need to take the exit angle in the other direction; and as a result, the approach is obtained according to a sinusoid, and the DPRM always remains on the sidelines.

The closer you are to the far drive, the smaller the exit angles you need to take and the less time you have to go with these angles. Approaching the distant one, you need to switch all your attention to the near one and set a course for it in advance, without trying to accurately pass the DPRM. By the time the flight path is reached, and this is between the far and near, the heading should be close to the landing one, and the EAC should be close to 0°, naturally, taking into account the drift.

As for the control of the longitudinal channel, the peculiarity here is that the approach method itself requires keeping the vertical speed higher than the calculated one, which means the mode must be kept lower.

After passing the DPRM, the vertical speed must be maintained at the design speed,

which means adding a mode in advance.

A common mistake when approaching along the OSP is a late start of descent along the glide path and failure to maintain the calculated, i.e. 0.5–1 m/sec more, vertical speed, which is fraught with the overflight of the distant drive at a higher altitude and an increase in the vertical speed in the area where it must be kept strictly calculated. Such catching up of the glide path can continue all the way to the end, with the reduction of the mode below the calculated one, and there is a danger of forgetting that the vertical speed is significant and leveling will need to start higher with the proactive addition of the mode. Anyone who forgets about this in their enthusiasm to land strictly on the end and on the axle runs the risk of getting a decent overload on landing.

Up to an altitude of 150 meters, all parameters: heading, glide path, speed and vertical must be normal and stable. It happens that strong atmospheric disturbances throw the plane out of its glide path. Going down is not as scary as going up, and only requires a vigorous addition of the mode and a decrease in vertical speed with the restoration of parameters when approaching the glide path. If it kicks up, then there is no time to waste. An experienced pilot, with a smooth but energetic lowering of the nose, while simultaneously retracting the mode, can catch up with the glide path in one movement, increasing the vertical speed once to 7 m/sec., but in advance, even before approaching the glide path, he will add the mode to the calculated one and in advance, before the glide path, will reduce the vertical to the calculated value. It is advisable to complete this operation to a height of 150 meters in order to stabilize the parameters.

An inexperienced pilot will waste time and begin to catch up with the glide path at a slow pace and with a slight reduction in the mode, accelerate the speed and even if he catches up with the glide path, then on the runway he will have problems with high vertical and forward speeds.

I describe this method of catching up the glide path once only to show: the plane willingly loses altitude without having time to accelerate the forward speed, but it requires significant effort in order to then reduce the descent, and therefore, meaningful, proactive actions by the captain. And if this method can, within certain limits, be used in the DPRM region, then below the DPRM it is absolutely impossible, which will be discussed in detail below.

Regardless of the choice of approach system, the navigator is required to constantly monitor the direction of the drives, starting from the beginning of the fourth turn and until the flight of the main landing gear. There were cases of failure of the localization beacon or the aircraft's directional equipment, and OSP control saved the day.

It is also mandatory for the navigator to control altitude by distance. The right triangle must be maintained. On the command “No further!” the captain is obliged to immediately take the aircraft into level flight with a mode set 4-5 percent higher than the design mode on the glide path.

Due to the appearance of passengers large quantity radio equipment that can affect the operation of on-board systems on the glide path, it is possible for the aircraft to smoothly deviate from the established trajectory without triggering a warning alarm. The author of these lines had the opportunity to see how, with apparently properly working systems, the vertical speed began to gradually increase, and the director arrows stood in the center. And only the navigator’s warning “there is no further distance” and entering a visual flight prevented further development of the situation.

Operating experience of the Tu-154 has shown that the crews have learned to maintain the recommended glide path flight speeds (especially at low landing masses) by 10-15 km/h more. Of course, flying at a higher speed is somehow calmer and more guaranteed, but we must not forget that the landing parameters are calculated depending on exactly this speed - the speed of crossing the end. Therefore, it is advisable to cross the end at the speed recommended by the Flight Manual, that is, exactly corresponding to the actual landing weight. On the glide path, let the speed be a little higher, this guarantees controllability in a possible bumpy situation, but after the overshoot, the speed must be gradually reduced, and in other situations – quite energetically. One of the common mistakes of young pilots is that once they have selected the speed, they try to maintain it until leveling off, forgetting that at low altitudes the wind weakens and an increase in vertical speed is required, even if only slightly, but it accelerates the forward speed, and therefore requires a reduction in the speed.

The only time when the speed must be kept elevated is when landing in conditions of heavy icing and strong crosswinds. But in 20 years of flying on the Tu-154, I have never encountered severe icing, and I have not seen that the icing that sometimes occurs has any effect on the landing. However, the experience of old pilots who had to land on piston aircraft, adding the glide path mode to the nominal and even higher - the icing was so strong - says that if you really have to, God forbid, get into such conditions on a Tu-154, for example, in the waiting area, you must take them seriously. Here we must remember that such ice, in addition to disrupting aerodynamics, also significantly increases mass, and therefore, coupled with an increase in speed, kinetic energy, which during the run can only be extinguished by the decisive use of reverse until a complete stop.

As for landing with crosswinds, it will be discussed below.

Maintaining glide path speed in thermal bumpy conditions requires only patience. Typically, such conditions occur in light winds, and analyzing the behavior of the car on the glide path is easier. Sometimes speed deviations from the recommended ones are significant, but they are short-lived and, if the pilot is patient, do not require a change in mode. It is much more difficult here to maintain the recommended vertical speed and glide path.

In severe bumpiness, it is better to go to the VPR in automatic mode, with the “bumpiness” toggle switch turned on, not forgetting to set the IN-3 bar to the neutral position with the aileron trimmer, so that when the autopilot is turned off, there is no tendency for the aircraft to roll. The stability-controllability system copes well with the bumpiness, and the pilot saves his strength for the last 20 seconds.

In general, descending from a flight level in the helm control mode, approaching and landing manually are quite labor-intensive, and sometimes take so much effort that there is almost no energy left for the flyby. Personally, I never descend manually, and, moreover, I never force young co-pilots to do it. At the same time, instead of thoughtful analysis, they are engaged in the fight against iron. To those who prove that once in a while it will come in handy, I will answer: how many times has it come in handy for you? Not once for me. And these trainings should be left for light aviation. No need to hammer in nails with a computer. The iron must work for the pilot's hands, and the brain must control the iron. In order to play a huge organ, it is not at all necessary to pump air into the pipes with bellows.

I am talking here about the high art of flying a heavy aircraft. We are the elite of aviation. We are the masters. And the worker-peasant approach to this art is inappropriate.

So, on the glide path, a normal pilot must be able to maintain directional arrows within the circle and correct pitch disturbances, not allowing the glide path bar to deviate by more than a point, with an immediate return to the original mode, or with a stable tendency to return to it. In this case, the vertical speed is the basic parameter for analysis, and the instrument speed is an indicator of the tendency to change the vertical. The instrument is pitch and engine mode.

Maybe one of my colleagues will grin: well, it’s a lot... that’s all

it’s much easier, you do it yourself...

If you have such talent, then good luck, and may God grant that your hands retain their skill until retirement. I can't do this. I don’t have such a reaction, nor such a feeling that I can immediately with one movement - and in the kings. It's only in the movies that everything works out the first time. I have behind me a huge, scrupulous work on myself, many failures and a constant feeling of dissatisfaction. And it’s like that for every old pilot.

Although there are examples when the old captain’s instincts and acumen fail. Example

the Ivanovo disaster must constantly cool down other hotheads.

Approach- one of the final stages of an aircraft's flight, immediately preceding landing. Ensures that the aircraft is placed on a trajectory that is pre-landing line leading to the landing point.

The landing approach can be carried out either using radio navigation equipment (and in this case is called an instrument approach) or visually, in which the crew is oriented along the natural horizon line observed by the runway and other landmarks on the ground. In the latter case, the approach may be called a visual approach (VFR) if it is a continuation of an IFR flight (instrument flight rules) or a VFR approach if it is a continuation of a VFR flight (visual flight rules).

Glide slope(fr. glissade- “sliding”) is the flight path of an aircraft along which it descends immediately before landing. As a result of flying along the glide path, the aircraft enters the landing zone on the runway.

In paragliding, the base glide path is the straight path immediately before landing.

Glide slope angle is the angle between the glide path plane and the horizontal plane. The glide slope angle is one of the important characteristics of an airfield runway. For modern civil airfields it is usually in the range of 2-4.5°. The glide slope angle may be affected by the presence of obstacles in the airfield area.

In the Soviet Union, the typical value of the glide path angle was 2°40′. International organization civil aviation recommends UNG 3°.

Also, the process of descending an aircraft before landing is sometimes called a glide path.

Compared to other types aircraft the aircraft has the longest take-off phase and the most difficult to organize control. Take-off begins from the moment you start moving along the runway for the take-off run and ends at the transition altitude.

Take-off is considered one of the most difficult and dangerous stages of flight: during take-off, engines operating under conditions of maximum thermal and mechanical load may fail, the aircraft (relative to other phases of flight) is maximally fueled, and the flight altitude is still low. The biggest disaster in aviation history occurred on takeoff.

Specific takeoff procedures for each type of aircraft are described in the aircraft flight manual. Adjustments can be made by exit schemes and special conditions (for example, noise reduction rules), however, there are some general rules.

For acceleration, engines are usually set to takeoff mode. This is an emergency mode, the flight duration is limited to a few minutes. Sometimes (if the runway length allows) during takeoff, the nominal mode is acceptable.

Before each takeoff, the navigator calculates the decision speed (V 1), up to which the takeoff can be safely aborted and the aircraft will stop within the runway. The calculation of V 1 takes into account many factors, such as: runway length, its condition, coverage, altitude above sea level, weather conditions (wind, temperature), aircraft loading, alignment, and others. If the failure occurs at a speed greater than V1, the only solution is to continue the takeoff and then land. Most types of civil aviation aircraft are designed in such a way that, even if one of the engines fails on takeoff, the power of the others is sufficient to accelerate the aircraft to a safe speed and rise to the minimum altitude from which it is possible to enter the glide path and land the aircraft.

Before takeoff, the pilot lowers the flaps and slats to the designed position to increase lift while minimizing the aircraft's acceleration. Then, after waiting for permission from the air traffic controller, the pilot sets the engines to takeoff mode and releases the wheel brakes, and the plane begins its takeoff run. During the takeoff run, the pilot’s main task is to keep the car strictly along its axis, preventing its lateral displacement. This is especially important in windy weather. Up to a certain speed, the aerodynamic rudder is ineffective and steering occurs by braking one of the main landing gear. After reaching the speed at which the rudder becomes effective, control is performed by the rudder. The front landing gear on the take-off run is usually locked for turning (the aircraft turns with its help while taxiing). As soon as takeoff speed is reached, the pilot smoothly takes the helm, increasing the angle of attack. The nose of the plane rises (“Lift”), and then the entire plane lifts off the ground.

Immediately after lift-off, to reduce drag (at a height of at least 5 meters), the landing gear and (if any) exhaust lights are retracted, then the wing mechanization is gradually retracted. Gradual retraction is due to the need to slowly reduce the lift of the wing. If the mechanization is quickly retracted, the aircraft may drop dangerously. In winter, when the plane flies into relatively warm layers of air where engine efficiency drops, the drawdown can be especially deep. Approximately according to this scenario, the Ruslan disaster occurred in Irkutsk. The procedure for retracting the landing gear and wing mechanization is strictly regulated in the Flight Manual for each type of aircraft.

Once the transition altitude is reached, the pilot sets the standard pressure to 760 mm Hg. Art. Airports are located at different altitudes, and management by air is carried out in a single system, therefore, at the transition altitude, the pilot is required to switch from the altitude reference system from runway level (or sea level) to flight level (conditional altitude). Also, at the transition height, the engines are set to the nominal mode. After this, the take-off stage is considered completed, and the next stage of the flight begins: climb.

There are several types of aircraft takeoff:

• Taking off from the brakes. The engines are brought to maximum thrust mode, at which the aircraft is held on the brakes; after the engines have reached the set mode, the brakes are released and the take-off run begins.
• Takeoff with a short stop on the runway. The crew does not wait until the engines reach the required mode, but immediately begins the takeoff run (the engines must reach the required power up to a certain speed). At the same time, the takeoff length increases.
• Take off without stopping rolling start), "on the fly." The engines reach the desired mode during taxiing from the taxiway to the runway; it is used during high intensity flights at the airfield.
• Takeoff using special means. Most often, this is a takeoff from the deck of an aircraft-carrying ship under conditions of a limited runway length. In such cases, the short takeoff run is compensated by springboards, ejection devices, additional solid-fuel rocket engines, automatic landing gear wheel holders, etc.
• Taking off an aircraft with a vertical or short take-off. For example, the Yak-38.
• Taking off from the surface of the water.

Author: Dmitry Prosko Date: 02/06/2005 23:20
The course-glide path system (hereinafter we will call it KGS, as is customary in Russia) is the most common approach system at large and busy airfields. In addition, it is the most accurate, unless, of course, you count MLS - Microwave Landing System, which has not yet received the same wide distribution. Now we will try to figure out how this system works and how to teach how to use it. Of course, this article does not claim to be the most complete and only correct guide :), but as teaching aid at the initial stage it will help you a lot.

Composition and principle of operation of the CGS

All that we see on the instruments during landing are 2 intersecting bars indicating the position of the aircraft relative to the approach path. Let's try to understand why they move, and why the aircraft's flight and navigation system receives very accurate information about the aircraft's position.

So, what does the CGS consist of:

1. A localization beacon that provides guidance to the aircraft in the horizontal plane - along the course.
2. Glide path beacon that provides guidance in the vertical plane - along the glide path.
3. Markers signaling the moment of passing certain points on the approach trajectory. Usually markers are installed on DPRM and BPRM.
4. Receiving devices on board an aircraft that provide signal reception and processing.

Localization and glide path beacons are installed near the runway. Localizer - at the opposite end of the runway along the center line, glide path beacon on the side of the runway at a distance from the landing point from the runway threshold.

Now let's talk about how these beacons work. Let's take the localizer as a basis and look at its operation in a somewhat simplified manner. During operation, the beacon generates 2 different-frequency signals, which can be schematically shown as 2 lobes directed along the approach path.

If the plane is located exactly at the intersection of these two lobes, the power of both signals is the same, respectively, the difference in their powers is zero, and the instrument indicators show 0. We are on course. If the plane deviates to the left or to the right, then one signal begins to prevail over the other. And the further from the course line, the greater this predominance. As a result, due to the difference in signal strength, the aircraft receiver determines exactly how far we are from the course line.

The glide path beacon works exactly on the same principle, only in the vertical plane.

Reading instrument readings

So, we entered the KGS coverage area. The standards for the PNP have gone off scale, which means it’s time for us to figure out where we are and how we need to pilot the plane in order to accurately fit into the approach trajectory.

Depending on what device we have installed, the indication may change, but the basic principle remains unchanged - the bars (arrows, indices) show us the position approach trajectory relative to our location. On the instrument that we are now considering, our position relative to the course is shown by a vertical bar, and our position relative to the glide path is shown by a triangular index on the right side of the instrument.

The bars themselves seem to show us exactly where our trajectory is. If the course bar is on the left, then the course line is also on the left, which means we need to turn left. The same is true for the glide path - if the glide path index is lower, then we are going higher, and we need to increase the vertical speed in order to “catch up” with the glide path.

Now let's go through the different positions of the aircraft and look at the instrument display in the positions indicated in the general drawing.

1. We are on the course line and have not yet approached the glide path entry point. Everything is as it should be - the heading bar is exactly in the center, the glide path index is at the top. The glide path line passes above us and rushes into nowhere at an average angle of 2 degrees 40 minutes relative to the horizon. By the way, the glide slope angle (GSA) is different at different airfields. This depends on the terrain and other conditions. For example, at mountain airfields the temperature can be up to 4-5 degrees.

2. We are at the glide path entry point (GPS). This is the point formed by the intersection of the glide path with the height of the circle. The average distance of the TVG is approximately 12 km. Naturally, the higher the height of the circle and the smaller the UNG, the farther the TVG is from the runway threshold.

3. We are to the left and higher. We need to turn right and increase the rate of descent.

4. We are to the left and below. Let's tidy up the vertical one and turn it to the right.

5. We are to the right and higher. Let's move it to the left and increase the vertical one.

6. We are to the right and lower. Guess what needs to be done :)

Well, in general, that's all I wanted to tell you :)

Finally, I want to make one very important addition.

Please note that the closer we are to the runway, the less evolution of the aircraft should be, because the device becomes very sensitive. For example, if we are 10 km from the runway threshold, the position of the directional bar at the second point of the scale may mean a lateral deviation of 400 meters or more (this is for example). To complete the turn, we will need to change course by 4-5 degrees or more. If we are at a distance of 2 km, then this position of the bar means that the deviations have exceeded the maximum permissible, and the only thing left for us is to go around. The closer the plane is to the runway threshold, the closer to the center the directional bar should be. Ideally, of course, exactly in the center :) And accordingly, the closer we are, the less evolution of the aircraft should be. There is no point in introducing a 30-degree roll in the near-drive area. Firstly, it is dangerous at such a height, and secondly, you simply will not have time to turn it, given the inertia of the aircraft.

Those who live near airports know: most often, taking off airliners soar upward along a steep trajectory, as if trying to get away from the ground as quickly as possible. And indeed, the closer the earth is, the less opportunity there is to react to an emergency and make a decision. Landing is another matter.

And the 380 lands on a runway covered with water. Tests have shown that the aircraft is capable of landing in crosswinds with gusts of up to 74 km/h (20 m/s). Although reverse braking devices are not required by the FAA and EASA, Airbus designers decided to equip the two engines located closer to the fuselage with them. This made it possible to obtain an additional braking system, while reducing operating costs and reducing preparation time for the next flight.

Modern jet passenger airliner designed for flights at altitudes of approximately 9-12 thousand meters. It is there, in very rarefied air, that it can move in the most economical mode and demonstrate its optimal speed and aerodynamic characteristics. The period from the completion of the climb to the start of the descent is called the flight at cruising level. The first stage of preparation for landing will be the descent from the flight level, or, in other words, following the arrival route. The final point of this route is the so-called initial approach checkpoint. In English it is called Initial Approach Fix (IAF).

And the 380 lands on a runway covered with water. Tests have shown that the aircraft is capable of landing in crosswinds with gusts of up to 74 km/h (20 m/s). Although reverse braking devices are not required by the FAA and EASA, Airbus designers decided to equip the two engines located closer to the fuselage with them. This made it possible to obtain an additional braking system, while reducing operating costs and reducing preparation time for the next flight.

From the IAF point, movement begins according to the approach to the airfield and landing approach, which is developed separately for each airport. An approach according to the pattern involves a further descent, passing a trajectory defined by a number of control points with certain coordinates, often performing turns and, finally, entering the landing line. At a certain landing point, the airliner enters the glide path. The glide path (from the French glissade - sliding) is an imaginary line connecting the entry point to the beginning of the runway. Following the glide path, the aircraft reaches the MAPt (Missed Approach Point), or missed approach point. This point is passed at the decision altitude (DAL), that is, the altitude at which the missed approach maneuver must be initiated if, before reaching it, the pilot-in-command (PIC) has not established the necessary visual contact with landmarks to continue the approach. Before the flight, the PIC must already assess the position of the aircraft relative to the runway and give the command “Land” or “Leave”.

Landing gear, flaps and economy

On September 21, 2001, an Il-86 aircraft belonging to one of Russian airlines, landed at Dubai airport (UAE) without extending the landing gear. The case ended with a fire in two engines and the aircraft being written off - fortunately, no one was injured. There was no talk of a technical malfunction, they just forgot to release the landing gear.

Modern airliners, compared to aircraft of previous generations, are literally packed with electronics. They implement a fly-by-wire remote control system (literally “fly on a wire”). This means that the steering wheels and mechanization are driven by actuators that receive commands in the form of digital signals. Even if the plane is not flying in automatic mode, the movements of the helm are not transmitted directly to the rudders, but are recorded in the form of a digital code and sent to a computer, which will instantly process the data and issue a command to the actuator. In order to increase the reliability of automatic systems, the aircraft is equipped with two identical computer devices (FMC, Flight Management Computer), which constantly exchange information, checking each other. The FMC introduces flight mission indicating the coordinates of the points through which the flight path will pass. Electronics can guide the aircraft along this trajectory without human intervention. But the rudders and mechanization (flaps, slats, spoilers) of modern airliners are not much different from the same devices in models produced decades ago. 1. Flaps. 2. Interceptors (spoilers). 3. Slats. 4. Ailerons. 5. Rudder. 6. Stabilizers. 7. Elevator.

Economics has something to do with the background to this accident. The approach to the airfield and landing approach are associated with a gradual decrease in the speed of the aircraft. Since the amount of wing lift is directly dependent on both the speed and the wing area, in order to maintain enough lift to keep the car from stalling into a tailspin, the wing area must be increased. For this purpose, mechanization elements are used - flaps and slats. Flaps and slats perform the same role as the feathers that birds fan out before landing on the ground. When the speed of the start of mechanization extension is reached, the PIC gives the command to extend the flaps and, almost simultaneously, to increase the engine operating mode to prevent a critical loss of speed due to an increase in drag. The greater the angle the flaps/slats are deflected, the greater the operating mode required by the engines. Therefore, the closer to the runway the final release of the mechanization (flaps/slats and landing gear) occurs, the less fuel will be burned.

On domestic aircraft of older types, this sequence of mechanization release was adopted. First (20-25 km before the runway) the landing gear was released. Then, after 18-20 km, the flaps were set to 280. And already on the landing straight, the flaps were extended fully, to the landing position. However, nowadays a different technique has been adopted. In order to save money, pilots strive to fly the maximum distance “on a clean wing”, and then, before the glide path, reduce the speed by intermediately extending the flaps, then lower the landing gear, bring the flap angle to the landing position and land.

The figure shows a very simplified diagram of the approach and takeoff in the airport area. In fact, the schemes may differ noticeably from airport to airport, as they are compiled taking into account the terrain, the presence of high-rise buildings and no-fly zones nearby. Sometimes several schemes operate for the same airport depending on weather conditions. For example, in Moscow Vnukovo, when entering the runway (GDP 24), the so-called a short scheme, the trajectory of which lies outside the Moscow Ring Road. But in bad weather, planes enter in a long pattern, and the liners fly over the South-West of Moscow.

The crew of the ill-fated Il-86 also used the new technique and extended the flaps to the landing gear. Knowing nothing about new trends in piloting, the Il-86 automatic system immediately turned on a voice and light alarm, which required the crew to lower the landing gear. So that the alarm would not irritate the pilots, it was simply turned off, like turning off a boring alarm clock when you are asleep. Now there was no one to remind the crew that the landing gear still needed to be lowered. Today, however, there have already appeared examples of Tu-154 and Il-86 aircraft with modified signaling, which fly according to the approach method with the late release of mechanization.

According to actual weather

In news reports you can often hear a similar phrase: “Due to deteriorating weather conditions in the area of ​​airport N, the crews make decisions about takeoff and landing based on the actual weather.” This common cliche causes both laughter and indignation among domestic aviators. Of course, there is no arbitrariness in flying. When the aircraft passes the decision point, the pilot-in-command (and only he) makes the final call on whether the crew will land the aircraft or whether the landing will be aborted by a go-around. Even with the best weather conditions and the absence of obstacles on the runway, the pilot has the right to cancel the landing if, as the Federal Aviation Regulations say, he is “not confident in the successful outcome of the landing.” “Today, a missed approach is not considered a failure in the pilot’s work, but, on the contrary, is welcomed in all doubtful situations. It’s better to be vigilant and even sacrifice some amount of burned fuel than to put even the slightest risk to the lives of passengers and crew,” Igor Bocharov, chief of the flight operations headquarters of S7 Airlines, explained to us.

The course-glide path system consists of two parts: a pair of localization beacons and a pair of glide path beacons. Two localizers are located behind the runway and emit a directed radio signal along it at different frequencies at small angles. On the runway centerline, the intensity of both signals is the same. To the left and right of this direct signal, one of the beacons is stronger than the other. By comparing the intensity of the signals, the aircraft's radio navigation system determines which side and how far it is from the center line. Two glide path beacons are located in the area of ​​the landing zone and act in a similar way, only in the vertical plane.

On the other hand, the PIC is strictly limited in decision-making by the existing landing procedure regulations, and within the limits of these regulations (except for emergency situations such as a fire on board) the crew does not have any freedom to make decisions. There is a strict classification of landing approach types. For each of them, separate parameters are prescribed that determine the possibility or impossibility of such a landing under given conditions.

For example, for Vnukovo airport, an instrument approach using a non-precision type (via radio stations) requires passing a decision point at an altitude of 115 m with a horizontal visibility of 1700 m (determined by the weather service). In order to land before the runway (in this case 115 m), visual contact with landmarks must be established. For automatic landing according to ICAO category II, these values ​​are much smaller - they are 30 m and 350 m. Category IIIc allows for fully automatic landing with zero horizontal and vertical visibility - for example, in complete fog.

Safe hardness

Any air passenger with experience of flying with domestic and foreign airlines has probably noticed that our pilots land planes “softly”, while foreign ones land them “hard”. In other words, in the second case, the moment of touching the runway is felt in the form of a noticeable push, while in the first case, the plane gently “rubs” against the runway. The difference in landing style is explained not only by the traditions of flight schools, but also by objective factors.

First, let's clarify terminology. In aviation usage, a hard landing is a landing with an overload that greatly exceeds the norm. As a result of such a landing, the aircraft, in the worst case, receives damage in the form of residual deformation, and in the best case, it requires special maintenance aimed at additional monitoring of the condition of the aircraft. As Igor Kulik, leading pilot instructor of the flight standards department of S7 Airlines, explained to us, today a pilot who makes a real hard landing is suspended from flying and sent for additional training on simulators. Before taking off again, the offender will also have to undergo a test flight with an instructor.

The landing style on modern Western aircraft cannot be called hard - we are simply talking about increased overload (about 1.4-1.5 g) compared to 1.2-1.3 g, characteristic of the “domestic” tradition. If we talk about piloting techniques, the difference between landings with relatively less and relatively more overload is explained by the difference in the procedure for leveling the aircraft.

The pilot begins alignment, that is, preparation for touching the ground, immediately after flying over the end of the runway. At this time, the pilot takes the helm, increasing the pitch and moving the aircraft to a nose-up position. Simply put, the plane “lifts its nose,” which results in an increase in the angle of attack, which means a slight increase in lift and a drop in vertical speed.

At the same time, the engines are switched to the “idle gas” mode. After some time, the rear landing gear touches the strip. Then, reducing the pitch, the pilot lowers the nose gear onto the runway. At the moment of contact, spoilers (spoilers, also known as air brakes) are activated. Then, reducing the pitch, the pilot lowers the front strut onto the runway and turns on the reverse device, that is, additionally braking with the engines. Wheel braking is used, as a rule, in the second half of the run. The reverse is structurally made up of flaps that are placed in the path of the jet stream, deflecting some of the gases at an angle of 45 degrees to the course of the aircraft - almost in the opposite direction. It should be noted that on older domestic aircraft, the use of reverse during the run is mandatory.

Silence overboard

On August 24, 2001, the crew of an Airbus A330 flying from Toronto to Lisbon discovered a fuel leak in one of the tanks. It happened in the skies over the Atlantic. The ship's commander, Robert Pisch, decided to leave for an alternate airfield located on one of the Azores. However, along the way, both engines caught fire and failed, and there were still about 200 kilometers left to the airfield. Rejecting the idea of ​​landing on water, as giving virtually no chance of salvation, Pish decided to reach land in gliding mode. And he succeeded! The landing turned out to be hard - almost all the tires burst - but no disaster occurred. Only 11 people received minor injuries.

Domestic pilots, especially those operating Soviet-type airliners (Tu-154, Il-86), often complete the leveling procedure with a holding procedure, that is, they continue to fly over the runway for some time at an altitude of about a meter, achieving a soft touch. Of course, passengers like landings with holding more, and many pilots, especially those with extensive experience in domestic aviation, consider this style to be a sign of high skill.

However, today's global trends in aircraft design and piloting give preference to landing with an overload of 1.4-1.5 g. Firstly, such landings are safer, since a holding landing contains the threat of rolling out of the runway. In this case, the use of reverse is almost inevitable, which creates additional noise and increases fuel consumption. Secondly, the very design of modern passenger aircraft provides for contact with increased overload, since the activation of automation, for example, the activation of spoilers and wheel brakes, depends on a certain value of the physical impact on the landing gear (compression). In older types of aircraft this is not required, since the spoilers are turned on automatically after turning on the reverse. And the reverse is activated by the crew.

There is another reason for the difference in landing style, say, on the Tu-154 and A 320, which are similar in class. Runways in the USSR were often characterized by low load load, and therefore Soviet aviation tried to avoid too much pressure on the surface. The rear trolleys of the Tu-154 have six wheels - this design helped distribute the weight of the vehicle over large area upon landing. But the A 320 has only two wheels on racks, and it was originally designed for landing with a higher overload on more durable strips.

Islet of Saint Martin in Caribbean, divided between France and the Netherlands, gained fame not so much because of its hotels and beaches, but because of the landings of civilian airliners. Heavy wide-body aircraft such as Boeing 747 or A-340 fly to this tropical paradise from all over the world. Such cars need a long run after landing, but at Princess Juliana Airport the runway is too short - only 2130 meters - its end is separated from the sea only by a narrow strip of land with a beach. To avoid rolling out, Airbus pilots aim at the very end of the runway, flying 10-20 meters above the heads of vacationers on the beach. This is exactly how the glide path is laid out. Photos and videos of landings on the island. Saint-Martin has long been bypassed on the Internet, and many at first did not believe in the authenticity of these filmings.

Trouble on the ground

And yet, really hard landings, as well as other troubles, do happen during the final leg of the flight. As a rule, air accidents are caused by not one, but several factors, including piloting errors, equipment failure, and, of course, the elements.

The greatest danger is posed by the so-called wind shear, that is, a sharp change in wind strength with height, especially when this occurs within 100 m above the ground. Suppose an airplane is approaching the runway at an indicated speed of 250 km/h with zero wind. But, having descended a little lower, the plane suddenly encounters a tailwind with a speed of 50 km/h. The incoming air pressure will drop, and the plane's speed will be 200 km/h. The lift will also decrease sharply, but the vertical speed will increase. To compensate for the loss of lift, the crew will need to add engine mode and increase speed. However, the plane has a huge inertial mass, and it simply will not have time to instantly gain sufficient speed. If there is no headroom, a hard landing cannot be avoided. If the airliner encounters a sharp gust of headwind, the lifting force, on the contrary, will increase, and then there will be a danger of a late landing and rolling out of the runway. Landing on a wet and icy runway also leads to rollouts.

Man and machine

Approach types are divided into two categories, visual and instrumental.
The condition for a visual approach, as with an instrument approach, is the height of the cloud base and the runway visual range. The crew follows the approach pattern, guided by the landscape and ground objects or independently choosing the approach trajectory within the designated visual maneuvering zone (it is set as a half circle with the center at the end of the runway). Visual landings allow you to save fuel by choosing the shortest route this moment approach trajectory.
The second category of landings is instrumental (Instrumental Landing System, ILS). They, in turn, are divided into accurate and inaccurate. Precision landings are carried out using a course-glide path, or radio beacon, system, using localizer and glide path beacons. The beacons form two flat radio beams - one horizontal, depicting the glide path, the other vertical, indicating the course to the runway. Depending on the equipment of the aircraft, the course-glide path system allows for automatic landing (the autopilot itself guides the plane along the glide path, receiving a signal from radio beacons), director landing (on the command instrument, two director bars show the positions of the glide path and course; the task of the pilot, working at the helm, is to place them accurately in the center of the command device) or approach using beacons (crossed arrows on the command device depict the course and glide path, and the circle shows the position of the aircraft relative to the required course; the task is to align the circle with the center of the crosshair). Non-precision landings are performed in the absence of a glide path system. The line of approach to the end of the strip is set by radio equipment - for example, far and near driving radio stations with markers installed at a certain distance from the end (DPRM - 4 km, BPRM - 1 km). Receiving signals from “drives”, magnetic compass in the cockpit shows whether the aircraft is to the right or left of the runway. At airports equipped with a course-glide path system, a significant portion of landings are made using instruments in automatic mode. The international organization ICFO has approved a list of three categories of automatic landing, with category III having three subcategories - A, B, C. For each type and category of landing, there are two defining parameters - the horizontal visibility distance and the vertical visibility height, also known as the decision height. In general, the principle is this: the more automation is involved in landing and the less the “human factor” is involved, the lower the values ​​of these parameters.

Another scourge of aviation is crosswinds. When, when approaching the end of the runway, the plane flies at a drift angle, the pilot often has the desire to “turn” the control wheel and put the plane on the exact course. When turning, a roll occurs, and the plane exposes a large area to the wind. The liner blows even further to the side, and in this case the only correct decision is a go-around.

In crosswinds, the crew often tries not to lose control of direction, but ends up losing control of altitude. This was one of the reasons for the Tu-134 crash in Samara on March 17, 2007. The combination of “human factor” and bad weather cost the lives of six people.

Sometimes incorrect vertical maneuvering during the final leg of the flight leads to a hard landing with catastrophic consequences. Sometimes the plane does not have time to descend to the required altitude and ends up above the glide path. The pilot begins to “give back the helm”, trying to enter the glide path. At the same time, the vertical speed increases sharply. However, with an increased vertical speed, a greater height is required at which leveling must begin before touching down, and this dependence is quadratic. The pilot begins leveling off at a psychologically familiar altitude. As a result, the aircraft touches the ground with a huge overload and crashes. The history of civil aviation knows many such cases.

Airliners of the latest generations can well be called flying robots. Today, 20-30 seconds after takeoff, the crew can, in principle, turn on the autopilot and then the car will do everything itself. If no emergency occurs, if an accurate flight plan is entered into the on-board computer database, including the approach path, if the arrival airport has the appropriate modern equipment, the airliner will be able to fly and land without human intervention. Unfortunately, in reality, even the most advanced technology sometimes fails; aircraft of outdated designs are still in operation, and the equipment of Russian airports continues to leave much to be desired. That is why, when rising into the sky and then descending to the ground, we still largely depend on the skill of those who work in the cockpit.

We would like to thank the representatives of S7 Airlines for their help: Il-86 instructor pilot, Chief of Flight Operations Staff Igor Bocharov, Chief Navigator Vyacheslav Fedenko, Instructor Pilot of the Flight Standards Department Directorate Igor Kulik