Those who live in the area of ​​airports know that most often taking off liners soar up a steep trajectory, as if trying to get away from the ground as soon as possible. Indeed, the closer the earth, the less the ability to respond to an emergency and make a decision. Landing is another matter.

A 380 lands on a runway covered with water. Tests have shown that the aircraft is capable of landing in crosswinds with gusts up to 74 km/h (20 m/s). Although FAA and EASA regulations do not require reverse braking devices, Airbus designers decided to equip two engines 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.

A modern jet passenger liner is designed to fly 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 interval from the completion of the climb to the beginning of the descent is called cruise flight. 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).

A 380 lands on a runway covered with water. Tests have shown that the aircraft is capable of landing in crosswinds with gusts up to 74 km/h (20 m/s). Although FAA and EASA regulations do not require reverse braking devices, Airbus designers decided to equip two engines 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 aerodrome and landing approach, which is developed separately for each airport. The approach according to the scheme involves further descent, passing the trajectory set by a number of control points with certain coordinates, often making turns and, finally, reaching the landing straight. At a certain point on the landing straight line, the liner enters the glide path. Glide path (from French glissade - glide) is an imaginary line connecting the entry point to the start of the runway. Passing along the glide path, the aircraft reaches the MAPt (Missed Approach Point), or go-around point. This point is passed at the decision-making height (CLL), i.e. the height at which the go-around maneuver should be initiated if, prior to reaching it, the pilot-in-command (PIC) did not establish the necessary visual contact with landmarks to continue the approach. Before the PLO, the PIC should already assess the position of the aircraft relative to the runway and give the command “Sit down” or “Leave”.

Chassis, flaps and economics

On September 21, 2001, an Il-86 aircraft belonging to one of the Russian airlines landed at Dubai Airport (UAE) without releasing the landing gear. The case ended in a fire in two engines and the decommissioning of the liner - fortunately, no one was hurt. There was no question of a technical malfunction, just the chassis ... they forgot to release it.

Modern liners, compared to aircraft of past generations, are literally packed with electronics. They implement a fly-by-wire electrical remote control system (literally “fly on the wire”). This means that the rudders and mechanization are set in motion by actuators that receive commands in the form of digital signals. Even if the aircraft is not flying in automatic mode, the movements of the steering wheel are not directly transmitted to the rudders, but are recorded in the form of a digital code and sent to a computer that will instantly process the data and give a command to the actuator. In order to increase the reliability of automatic systems, two identical computer devices (FMC, Flight Management Computer) are installed in the aircraft, which constantly exchange information, checking each other. In FMC, a flight task is entered with the indication of 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 liners are not much different from the same devices in models released decades ago. 1. Flaps. 2. Interceptors (spoilers). 3. Slats. 4. Ailerons. 5. Rudder. 6. Stabilizers. 7. Elevator.

Economics is at the heart of this accident. The approach to the aerodrome and the landing approach are associated with a gradual decrease in the speed of the aircraft. Since the amount of wing lift is directly related to both speed and wing area, in order to maintain enough lift to keep the car from stalling into a tailspin, the wing area needs to 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 falling to the ground. Upon reaching the speed of the beginning of the release of mechanization, the PIC gives a command to extend the flaps and almost simultaneously - to increase the engine operation mode to prevent a critical loss of speed due to an increase in drag. The greater the deflection angle of the flaps/slats, the greater the mode required by the engines. Therefore, the closer to the runway the final release of mechanization (flaps / slats and landing gear) takes place, the less fuel will be burned.

On domestic aircraft of old types, such a sequence for the release of mechanization was adopted. First (for 20-25 km to the runway) the chassis was produced. Then for 18-20 km - flaps at 280. And already on the landing straight, the flaps were fully extended, into the landing position. Today, however, a different methodology has been adopted. In order to save money, pilots tend to fly the maximum distance “on a clean wing”, and then, before the glide path, reduce the speed by intermediate flap extension, then extend the landing gear, bring the flap angle to the landing position and land.

The figure shows a very simplified approach to landing and takeoff in the airport area. In fact, schemes can differ markedly from airport to airport, as they are drawn up taking into account the terrain, the presence of high-rise buildings near and no-fly zones. Sometimes there are several schemes for the same airport depending on weather conditions. So, for example, in the Moscow Vnukovo, when entering the runway (VVP 24), the so-called. a short circuit, 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 automation immediately turned on the voice and light alarm, which required the crew to release the landing gear. So that the signaling would not irritate the pilots, it was simply turned off, just as a boring alarm clock is turned off when awake. Now there was no one to remind the crew that the chassis still needed to be released. Today, however, copies of the Tu-154 and Il-86 aircraft with modified signaling have already appeared, which fly according to the approach method with a late release of mechanization.

Based on actual weather

In information reports, you can often hear a similar phrase: "Due to the deterioration of weather conditions in the area of ​​​​airport N, crews make decisions about takeoff and landing based on the actual weather." This common stamp causes domestic aviators to laugh and indignant at the same time. Of course, there is no arbitrariness in the flying business. When the aircraft passes the decision point, the aircraft commander (and only he) finally announces whether the crew will land the liner or the landing will be aborted by a go-around. Even under the best weather conditions and the absence of obstacles on the runway, the PIC has the right to cancel the landing if, as the Federal Aviation Rules say, he is “not sure of the successful outcome of the landing.” “Go-around today is not considered a miscalculation in the work of the pilot, but on the contrary, it is welcomed in all situations that allow for doubt. It is better to be vigilant and even sacrifice some amount of burned fuel than put the lives of passengers and crew at even the slightest risk,” explained Igor Bocharov, Head of Flight Operations at S7 Airlines.

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

On the other hand, in making decisions, the PIC is strictly limited by the existing landing procedure regulations, and within this regulation (except for emergency situations like a fire on board), the crew does not have any decision-making freedom. There is a strict classification of 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, a non-precision instrument approach (according to locators) requires passing a decision point at an altitude of 115 m with a horizontal visibility of 1700 m (determined by the weather service). To land before the VLOOKUP (in this case, 115 m), visual contact with landmarks must be established. For an automatic landing according to ICAO category II, these values ​​are much lower - they are 30 m and 350 m. Category IIIc allows a 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 “hard”. In other words, in the second case, the moment of touching the strip is felt in the form of a noticeable push, while in the first case, the aircraft gently “grinds” to the strip. The difference in landing style is explained not only by the traditions of flight schools, but also by objective factors.

Let's start with some terminological clarity. A hard landing in aviation is called a landing with an overload that greatly exceeds the standard. As a result of such a landing, the aircraft, at worst, suffers damage in the form of permanent deformation, and at best, requires special maintenance aimed at additional control 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 made a real hard landing is removed from flights and sent for additional training in simulators. Before going on a flight again, the offender will also have to test-training flight with an instructor.

The landing style on modern Western aircraft cannot be called hard - it's just about increased overload (about 1.4-1.5 g) compared to 1.2-1.3 g, characteristic of the "domestic" tradition. In terms of piloting technique, the difference between landings with relatively less and relatively more g-loads is explained by the difference in the procedure for leveling the aircraft.

To leveling, that is, to prepare for touching the ground, the pilot proceeds immediately after passing the end of the runway. At this time, the pilot takes over the helm, increasing the pitch and transferring the aircraft to the pitching position. Simply put, the aircraft “turns its nose”, which results in an increase in the angle of attack, which means a small increase in lift and a drop in vertical speed.

At the same time, the engines are transferred to the “idle gas” mode. After some time, the rear landing gear touches the strip. Then, reducing the pitch, the pilot lowers the front strut onto the runway. At the moment of contact, spoilers (spoilers, they are also 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 slows down with engines. Wheel braking is applied, as a rule, in the second half of the run. The reverse is structurally made up of shields that are placed in the path of the jet stream, deflecting part 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 aircraft of old domestic types, the use of reverse during the run is mandatory.

Silence on the sidelines

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 took place in the sky over the Atlantic. The commander of the ship, Robert Pish, decided to leave for an alternate airfield located on one of the Azores. However, on the way, both engines caught fire and failed, and there were still about 200 kilometers to the airfield. Rejecting the idea of ​​landing on the water, as giving almost no chance of salvation, Pish decided to make it to land in gliding mode. And he succeeded! The landing turned out to be tough - almost all the pneumatics burst - but the disaster did not happen. Only 11 people received minor injuries.

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

However, today's global trends in aircraft design and piloting prefer landing with an overload of 1.4-1.5 g. Firstly, such landings are safer, since holding landings contain the risk 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 a touchdown with increased g-load, since the operation 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). This is not required in older types of aircraft, since the spoilers are switched on there automatically after turning on the reverse. And the reverse is turned on by the crew.

There is another reason for the difference in landing style, say, on the Tu-154 and A 320, which are close in class. Runways in the USSR were often characterized by low cargo density, and therefore in Soviet aviation they tried to avoid too much pressure on the surface. The Tu-154 rear pillar bogies have six wheels each - this design contributed to the distribution of the weight of the machine over a large area during landing. But the A 320 has only two wheels on the racks, and it was originally designed for landing with more overload on stronger lanes.

The island of Saint Martin in the Caribbean, divided between France and the Netherlands, has become famous not so much because of its hotels and beaches, but thanks to the landings of civilian liners. Heavy wide-body aircraft such as the Boeing 747 or A-340 fly to this tropical paradise from all over the world. Such cars need a long run after landing, however, at the airport of Princess Juliana, the strip 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 strip, flying 10-20 meters above the heads of vacationers on the beach. This is how the trajectory of the glide path is laid. Photos and videos with landings on about. Saint-Martin has long bypassed the Internet, and many at first did not believe in the authenticity of these filming.

Trouble on the ground

And yet, really hard landings, as well as other troubles, happen on the final leg of the flight. As a rule, not one, but several factors lead to accidents, including piloting errors, equipment failure, and, of course, the elements.

A great danger is the so-called wind shear, that is, a sharp change in wind strength with height, especially when it occurs within 100 m above the ground. Suppose an aircraft is approaching the runway at an IAS 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 pressure of the incoming air will drop, and the speed of the aircraft will be 200 km/h. The lifting force will also drop sharply, but the vertical speed will increase. To compensate for the loss of lift, the crew will need to add engine power and increase speed. However, the aircraft 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 liner encounters a sharp gust of headwind, the lift, 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 strip also leads to rollouts.

Man and machine

Approach types fall into two categories, visual and instrumental.
The condition for a visual approach, as with an instrument approach, is the height of the base of the clouds and the visual range on the runway. The crew follows the approach pattern, focusing on the landscape and ground objects, or independently choosing the approach trajectory within the allocated visual maneuvering zone (it is set as a half circle centered at the end of the runway). Visual landings allow you to save fuel by choosing the shortest approach path at the moment.
The second category of landings is instrumental (Instrumental Landing System, ILS). They, in turn, are divided into accurate and inaccurate. Precise landings are made using a course-glide path, or radio beacon, system, with the help of course 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 steers the aircraft along the glide path, receiving a signal from radio beacons), director landing (on the command device, two director bars show the positions of the glide path and heading; the task of the pilot, operating the helm, is to place them accurately in the center of the command device) or beacon approach (the 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 combine the circle with the center of the crosshairs). Inaccurate landings are performed in the absence of a course-glide path system. The line of approach to the end of the strip is set by a radio-technical means - for example, installed at a certain distance from the end of the far and near driving radio stations with markers (LBM - 4 km, BBM - 1 km). Receiving signals from the "drives", the magnetic compass in the cockpit shows whether the plane is to the right or left of the runway. At airports equipped with a course-glide path system, a significant part of landings are made on instruments in automatic mode. The ICFO international organization has approved a list of three categories of automatic landing, and category III has three subcategories - A, B, C. For each type and category of landing, there are two defining parameters - horizontal visibility distance and vertical visibility height, it is also decision height. In general, the principle is as follows: the more automation is involved in the landing and the less the “human factor” is involved, the lower the values ​​of these parameters.

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

In a crosswind, the crew often tries not to lose control of the direction, but eventually loses control of the height. This was one of the reasons for the Tu-134 crash in Samara on March 17, 2007. The combination of "human factor" with bad weather cost the lives of six people.

Sometimes a hard landing with catastrophic consequences results from incorrect vertical maneuvering on the final leg of the flight. Sometimes the plane does not have time to descend to the required height and is above the glide path. The pilot begins to "give the helm", trying to enter the trajectory of the glide path. In this case, the vertical speed sharply increases. However, with increased vertical speed, a greater height is also required, at which alignment must be started before touching, and this dependence is quadratic. The pilot, on the other hand, proceeds to equalize at a psychologically familiar height. 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 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 there are no emergencies, 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 liner 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 be desired. That is why, 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: Pilot Instructor Il-86, Chief of Flight Operations Staff Igor Bocharov, Chief Navigator Vyacheslav Fedenko, Pilot Instructor of the Flight Standards Department Directorate Igor Kulik

Flight practice on Tu-154 aircraft Vasily Ershov

In glidepath.

In glidepath.

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

Pilot's inability to keep the director's arrow in the center all the time, neglect

the stability of the car's movement along the course, all sorts of theories on the "selection" of the course when using the director system, entering the course at the last stage - all this is a sign of a person's misunderstanding of a simple truth. It is impossible to solve the main task, constantly being distracted by an annoying trifle: “some” course.

It is impossible to ride a bike well by constantly comparing the side of your lean and the side and amount of handlebar deflection. Until you get a reflex.

This is the kind of reflex that a pilot should have on the director arrow. The position of the arrow not in the center should cause discomfort. The reaction to the deflection of the pointer must be automatic. A sense of alignment must be developed. Whoever has it always strives exactly to 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 keeping the course reflexively, then all his attention can be directed to the analysis of the behavior of the machine along the longitudinal channel. Such a pilot is more likely to solve this problem without errors.

The task of the aircraft movement along the 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 external forces are applied to the aircraft, 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 upset 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, it is quite possible to judge the professionalism of the pilot.

Most often, the pilot, by his inability to pre-calculate the mode on the glide path, creates difficulties for himself. Figuratively speaking, it “flies behind the aircraft”, reacting to disturbances by changing the regime and pitching.

This style of piloting reminds me of an inexperienced driver driving through our Russian streets. I saw the hatch - I drove around, I saw the hatch - I drove around, I saw the hatch - I drove around ... Yes, stand in another row or something. No, he is reacting. Such control of the aircraft is still the same consumerism of movement, the same principle of "gas - brake".

So, we have a task: the constancy of the instrumental and vertical speeds. Their calculated values ​​are known: roughly, 270 and 4, respectively. How to build an analysis of the behavior of the car on the glide path, "from what to dance"?

"Dancing" from vertical speed. If it is stable, then the entry is stable. If the vertical is stable to the end, then the approach is ideal, the problem is solved, and it remains only to land.

If the vertical speed, while maintaining the glide path arrow in the center, began to increase, then either a tailwind component appeared, or the opposite one fell.

If such a phenomenon occurs after the LBM, then it is usually associated with a weakening of the wind near the ground. If it is at a height, then it should be remembered that a change was expected, maybe a wind shear.

In any case, an increase in vertical speed entails an increase in translational speed. But - only under 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 are in effect. If the increase in vertical speed is associated with suction under the glide path, then the director arrow will vigorously go up at the same pitch and at the same speed.

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

The pilot constantly analyzes the cause of the change in vertical speed. Either these are his technical errors, the buildup in pitch; either it is a change in the wind; or changes in temperature and air density that affect the amount of thrust in the same mode and the amount of lift at the same translational speed. In the latter case, the rise in vertical is the inevitable consequence of the pilot reducing the pitch angle in order to keep the glide path needle centered.

Either the pilot keeps the increased mode and accelerates the speed, and the aircraft tends 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 cause of the change in vertical speed, the pilot must evaluate whether it is possible to return to the original flight mode only by deflecting the yoke if it was his technical error, or whether it is necessary to change the thrust of the engines if flight conditions have changed with altitude, or wait until the disturbance disappears, and wait until the machine, which is stable in speed, returns to its original mode on its own.

In any of these cases, it is necessary to 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 impulse in pitch, immediately returning the helm to its original position. Trimmer click there - 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 decreases. The director returned to the center - the calculated vertical line is immediately established. If the director strives to go up again and again, this is already a tendency: it is necessary to reduce the vertical speed; what is the reason?

All this analysis is carried out at 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 pushed above the glide slope... by a travel companion? Big mode? Inversion? Strong counter gust?

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

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

If this does not take into account the vertical speed, and, usually, the pitch ranges accompanying its jumps, then, with the formal maintenance of the course and glide path, with a constant indicated speed, an off-design high vertical speed is still quite possible in front of the butt, the correction of which introduces an adjustment into glide path keeping, and the correction of the glide path keeping error can add up with an already not calculated vertical speed.

In the narrowing wedge of possible deviations - attention and subtlety of movements are no longer enough; if this still diverts attention to maintaining the course, the likelihood of a gross error increases.

The whole point of the analysis is to keep the vertical speed at which an 80-ton aircraft approaches the ground constant. In order to pay it off, simple steps are required. But if the vertical speed near 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

an ordinary pilot is also able to withstand the parameters.

We fly in any, and even very difficult conditions, when all the strength of his will, all his talent, all his ability to control the situation is required from the captain - and, especially, the ability for subtle analysis in conditions of acute time pressure. And the more the captain is accustomed to analyze the situation, the finer his flair develops, the intuition that 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 specifics of our work is that we often have to fly in winter on northern airfields, where severe frosty 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, wind shear is not uncommon, accompanied by turbulence and jumps in IAS.

I had to land in the conditions of a surface polar front, with strong winds, at temperatures below -30 °, and, without counting on a frosty inversion, I nevertheless got into conditions of transition from warmer to colder layers. just at an altitude of 150 meters - with a full set of all the troubles that accompany the inversion. Our RLE limits the reduction of the engine mode on the glide path 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 was tested in conditions of frosty inversions for such a long time as we fly it under these conditions.

The restriction on the “not lower than 75%” mode for the “M” machine puts the crew in a frosty winter in difficult conditions. Sometimes on a light car in calm, the required mode even at the entrance to the glide path is already 78-76%. When approaching the ground, the air condenses so much that the 75% mode creates too much thrust, and the plane starts to accelerate. Reduce speed does not give a limit; increasing vertical speed only adds acceleration. On limited lanes, this leads to such a flight 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 figure or the actual behavior of the machine. The number 75 is calculated for wind shear in summer heat and is quite real. In conditions of low temperatures, it is on the border of absurdity.

The aircraft in such conditions flies perfectly and at modes less than 75%, up to low gas as needed. 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 on modes close to the idle mode, you need to carefully monitor the speed trend and add the mode in time before leveling, if a tendency to its fall is noticed.

In any case, landing at low temperatures requires a timely reduction in engine power, and the closer to the ground, the more energetically. Here the point is also that the headwind usually decreases towards the ground, which means that the ground speed increases, and some increase in vertical is required. A typical mistake of young pilots after a VPR is to go above the glide path, precisely for this reason. And the car must be pressed, which means that it is time to reduce the mode.

Trends must be anticipated. If the pilot, correcting, for example, the deviation from the glide path upwards, removed the mode and presses the car from above to the glide path, then you need to 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 the one with 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 an autothrottle. Without instruments at his disposal to show the deviation of the machine from the trajectory, the flight engineer will always lag behind in his response only to changes in speed.

The same applies to the use of a very imperfect autothrottle. I have not used it since the Shilak disaster and do not recommend it to others. He is not able to respond to speed changes by changing the mode within 1-2%, he not only does not participate in the analysis of the behavior of the machine, but, on the contrary, introduces dissonance and confuses the thinking pilot. But for consumers bypassing hatches on the road - please. On a mark of "3" he is an assistant.

About portions of the regime. RLE gives too broad standards. I always use one percent. Of course, in a strong chatter (to put it more precisely, in a “strong chatter”) you have to use large portions, but if possible I still try to endure and catch the main trend among the speed jumps, forestalling it with the same one percent.

We must always remember that 1% of the regime is tons of thrust. The range from 70 to 95% in flight includes thrust from 500 kg to 10 tons. Count yourself. If I allow myself to periodically apply and immediately remove 5 tons of thrust on the glide path, I will never achieve a rectilinear uniform movement.

The same goes for the course. Watching from the side how the young pilot turns the steering wheel, how he, all in business, corrects non-existent deviations - I suggest that he give up control. Does it fly by itself? And after all, it flies by itself, if it is streamed. By the way, this should become a rule for both young and experienced pilots. Quit, make sure: am I too constrained? Am I holding the steering wheel?

But the closer to the ground, the narrower the wedge, or rather, the cone of deviations, the more precise, 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 OSB system on a heavy aircraft requires strict adherence to the design parameters, which is possible only with the well-coordinated work of the entire crew. There is no course and glide path control, but there is only an approximate direction and an approximate, with a margin, vertical speed. Well, if there is a control for deletion; it is good if a simple direction finder is used. The course is easier to maintain using the ACS in the "ZK" mode. At the same time, one should always remember about one feature of the drive approach. The exit angle should always be taken half as much as it seems; the exit time is also taken half as much as desired. Make no mistake.

Having studied at one time on the piston IL-14, I had plenty of time to observe the OSP runs of my fellow listeners, being constantly behind them in a spacious, not like the current cockpit. And here I realized that the pilot (and me too) has an inherent desire to get on the course faster and more abruptly. 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, but the ARC is still late and cannot convincingly show that you are already on the other side. And when it shows, it is necessary to take the exit angle in the other direction; and as a result, the entry is obtained along a sinusoid, and the DPRM always remains on the sidelines.

The closer to the far drive, the smaller exit angles you need to take and the less time you need to go with these angles. Approaching the far one, it is necessary to switch all attention to the near one and take a course on it in advance, without trying to pass the DPRM exactly. By the time the VPR is reached, and this is between the far and the near, the heading should be close to the landing one, and the KUR should be close to 0o, of course, taking into account the drift.

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

After the passage of the DPRM, the vertical speed must be kept at the calculated one,

which means adding a mode in advance.

A common mistake when approaching the OSP is the late start of the descent along the glide path and failure to maintain the calculated, i.e., 0.5–1 m / s more, vertical speed, which is fraught with the passage of a long-range drive at a higher altitude and an increase in vertical speed in the area where it must be kept strictly calculated. Such a catch-up of the glide slope can continue to the very end, with the mode being lowered than the calculated one, and there is a danger of forgetting that the vertical speed is significant and it will be necessary to start leveling higher with a proactive addition of the mode. Whoever forgets about this in his passion to get strictly on the end and on the axis, he risks getting a decent overload on landing.

Up to a height 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 the glide path. Down is not as scary as up, and requires only 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, by smoothly but energetically lowering the nose, with simultaneous cleaning of the regime, can catch up with the glide path in one movement, increasing the vertical speed to 7 m / s once, but in advance, even before approaching the glide path, he will add the regime to the calculated one and in advance, to the glide path, will decrease the vertical to the calculated value. It is desirable to complete this operation before a height of 150 meters in order to stabilize the parameters.

An inexperienced pilot will miss the time and start to catch up with the glide path at a slow pace and with a slight cleaning of the regime, accelerate the speed, and if he catches up with the glide path, then he will have problems with high vertical and forward speeds on the VFR.

I describe this method of a one-time glide path catch-up, only to show that the aircraft willingly loses altitude without having time to accelerate forward speed, but it requires significant efforts to then reduce the descent, which means meaningful, proactive actions by the captain. And if this method can, within certain limits, be used in the area of ​​the DPRM, then it is categorically impossible below the VPR, which will be discussed in detail below.

Regardless of the choice of the approach system, the navigator is obliged to constantly control the direction by the drives, starting from the beginning of the fourth turn - and until the flight of the BRM. There were cases of failure of the localizer or the course equipment of the aircraft, and the control of the OSB saved.

It is also mandatory for the navigator to control the height of the distance. The right triangle must be maintained. At the command "No further!" the captain is obliged to immediately bring the car into level flight with the setting of the mode, which is 4-5 percent higher than the design mode on the glide path.

Due to the appearance of a large number of radio equipment in passengers, which can affect the operation of on-board systems on the glide path, the aircraft may smoothly deviate from the established trajectory without triggering a warning alarm. The author of these lines had the opportunity to see how, with externally working systems, the vertical speed began to increase smoothly, and the director arrows stood in the center. And only the warning of the navigator "there is no further" and the exit to the visual flight prevented the further development of the situation.

Tu-154 operation experience has shown that crews have learned to hold 10-15 km/h more recommended flight speeds on the glide path (especially at low landing weights). Of course, flying at a higher speed is somehow calmer, more guaranteed, but we must not forget that the landing parameters are calculated depending on this particular speed - the speed of crossing the butt. Therefore, it is desirable to cross the butt 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 bumpiness, but after the VPR, the speed must be gradually reduced, and in other situations - and quite vigorously. One of the common mistakes young pilots make is that once they pick up the speed, they tend to keep it until the leveling off, forgetting that at low altitudes the wind weakens and an increase in vertical speed is required, albeit slightly, but accelerating forward speed, and therefore requiring a reduction in mode.

The only time you need to keep the speed high is when landing in conditions of heavy icing and with a strong side wind. But in 20 years of flying the Tu-154, I never got into heavy icing, and I didn’t see that the icing, which sometimes I have to get into, somehow affected the landing. However, the experience of old pilots who had to land on piston aircraft, adding the mode on the glide path to the nominal and even higher - there was such a strong icing - says that if you really have to, God forbid, get into such conditions on the Tu-154, for example, in the waiting area, then you need to take them seriously. Here it must be remembered that such ice, in addition to disrupting aerodynamics, also significantly increases the mass, and therefore, coupled with an increase in speed, and kinetic energy, which can be extinguished on the run only by resolutely applying reverse to a complete stop.

As for landing with a crosswind, attention will be paid to it below.

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

It is better to go into a strong turbulence before the VPR in automatic mode, with the “in turbulence” toggle switch turned on, not forgetting to set the IN-3 bar to the neutral position with the aileron trim switch so that when the autopilot is turned off, there is no desire to roll the aircraft. The stability-handling system copes well with the bumpiness, and the pilot saves strength for the last 20 seconds.

In general, descent from the flight level in the helm control mode, manual entry and landing are quite laborious, and sometimes they take so much strength that there are almost none left by the time of flight. Personally, I never manually descend, 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 sometime it will come in handy, I will answer: how many times did it come in handy for you? To me, never. And these trainings should be left for light aviation. You don't have to drive nails in with a computer. Iron should work for the hands of the pilot, and the brain should control the iron. In order to play the 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 airliner. We are the aviation elite. We are masters. And the worker-peasant approach to this art is inappropriate.

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

Maybe one of my colleagues will chuckle: well, heaped up ... yes, that's all

it's much easier, hands do it themselves ...

If you have such a talent - yes to health, and God forbid your hands to keep their skills until retirement. I can't do this. I have neither such a reaction, nor such a flair, so that with one movement at once - and in kings. It's only in the movies that everything works out the first time. I have behind me a huge, scrupulous work on myself, a lot of failures and a constant feeling of dissatisfaction. And every old pilot is like that.

Although there are examples when the old captain is let down by flair and acumen. Example

Ivanovo catastrophe should constantly cool other hotheads.

Glide slope angle - the angle between the plane of the glide path and the horizontal plane. In the Soviet Union, the typical glide path angle was 2°40′. The International Civil Aviation Organization recommends a glide path angle of 3°. The angle of inclination of the glide slope is controlled either by radio engineering means (glide slope radio beacon), or by the pilot visually along the leading edge of the runway, or by the magnitude of the vertical rate of descent of the aircraft. The magnitude of the angle of inclination of the glide path can be affected by the presence of obstacles in the airfield area. The descent gradient must not exceed 5°. Flight along the glide path can be carried out in automatic, semi-automatic and manual control modes. As a result of glide path flight, the aircraft enters the landing zone on the runway.

Some aircraft fly on a broken glide path. The reusable spacecraft "Space Shuttle" and "Buran" flew along the glide path, the first section of which had an inclination angle of 19 °.

A glide path in a mathematical model is a parallel transfer of a vector along a geodesic curve, in which its angle with the geodesic remains unchanged. The rate of decline - "departure" down - is measured by the radius of curvature of the geodesic.

In paragliding, the basic glide slope is the direct path immediately before landing.

see also

Notes

Literature

• Glide path // Gas lift - Gogolevo. - M.: Soviet Encyclopedia, 1971. - (Great Soviet Encyclopedia: [in 30 volumes] / ch. ed. A. M. Prokhorov; 1969-1978, vol. 6).
• Glissade // Big Encyclopedic Dictionary / Ch. ed. A. M. Prokhorov. - 1st ed. - M.: Great Russian Encyclopedia, 1991. - ISBN 5-85270-160-2.
• Krysin, Leonid Petrovich. Glissade // Explanatory Dictionary of Foreign Words: Ok. 25000 words and phrases. - M.: Russian language, 1998. - 846 p. - (Library of Russian language dictionaries). - ISBN 5-200-02517-6.

glide path

Glide path

rectilinear trajectory of the movement of the aircraft, glider during landing approach. Descent along the glide path at an angle of 0.046-0.087 rad (2.64-5.0 degrees) to the horizontal plane provides the aircraft with a smooth, sliding and significantly reduces the dynamic load at the moment of touching the runway. This is especially important for large passenger airliners and heavy transport aircraft. At airfields, the glide path is set with the help of two radio beacons - glide path and localizer, which send radio beams in the direction of the landing aircraft, indicating the boundaries of the glide path in the inclined horizontal and vertical planes. The aircraft begins to descend along the glide path from a height of 200–400 m, the height of the glide path above the end of the runway is 15 m.

Encyclopedia "Technology". - M.: Rosman. 2006 .

glide path

(French glissade, literally - sliding)
1) rectilinear trajectory of the aircraft at an angle to the horizontal plane.
2) The straight-line trajectory along which the aircraft must descend during the landing approach. The nominal value of the angle of inclination of the G. to the horizontal plane is 0.046 rad, in exceptional cases the angle of inclination of the G. can reach up to 0.087 rad. At aerodromes, the glide path is set with the help of glide slope (GRM) and localizer (KRM) radio beacons, which are part of the aerodrome equipment. G. is formed by the intersection in space of two equisignal zones of the timing and RFC. The height of the equisignal zone of the timing above the end of the runway is 15 m. The movement of the aircraft along the horizontal line begins at an altitude of 200-400 m and ends with an alignment maneuver or go-around if the deviation from the horizontal line exceeds the allowable one.

Aviation: Encyclopedia. - M.: Great Russian Encyclopedia. Chief editor G.P. Svishchev. 1994 .

See what a "glissade" is in other dictionaries:

- (French glissade, from glisser to glide). Easy jump. Dictionary of foreign words included in the Russian language. Chudinov A.N., 1910. Glide path French. glissade, from glisser, to glide. Easy jump. Explanation of 25,000 foreign words included in ... ... Dictionary of foreign words of the Russian language

glide path- uh. glissade f. 1. Same as glide path. 2. The flight path of an aircraft, helicopter, glider, etc. during descent. BAS 2. The aircraft enters the final final glide slope. Owls. Ros. 7. 5. 1966. And its speed reduction is also impossible: ... ... Historical Dictionary of Gallicisms of the Russian Language

Trajectory, radio glide path, slip Dictionary of Russian synonyms. glide path n., number of synonyms: 3 radio glide path (1) ... Synonym dictionary

- (French glissade lit. glide), the flight path of an aircraft, helicopter, glider when descending ... Big Encyclopedic Dictionary

glide path- the descent profile established for vertical guidance at the final approach stage ... Source: Order of the Ministry of Transport of Russia dated 11/25/2011 N 293 (as amended on 04/26/2012) On the approval of the Federal Aviation Rules Organization of air ... ... Official terminology

s; and. [French] glissade] Avia. The trajectory of the descent of an aircraft, helicopter, glider. * * * Glide path (French glissade, literally sliding), the flight path of an aircraft, helicopter, glider when descending. * * * GLISSAD GLISSAD (French glissade, lit. ... ... encyclopedic Dictionary