“Flaps are very critical. "Commander, we are falling!" Why did the crew talk about flaps in the last seconds? Main types of flaps

According to experts, there have been cases when, instead of the “flaps-15” mode, the switch was accidentally placed in the wrong position.

As I wrote earlier, preliminary results of deciphering the flight recorders of the Tu-154 aircraft of the Russian Ministry of Defense that crashed near Sochi showed that the development of an emergency situation on board the airliner. Journalists from Moskovsky Komsomolets asked experts to comment on what happened on board the airliner.

According to one of the experts, if there is a mismatched flap release, then the jammed flap remains in the position in which it was stuck.

"That is intkbbee the system cuts off all electric motors that are used to release and retract the mechanization (flaps). At the same time, this tracking system releases or retracts a serviceable flap exactly at the same angle at which the jammed flap remained. In this regard, some people have a question: is it possible that the crashed Tu was so old that it was not equipped with such a system? No. I flew on this plane and I can say that only the very first Tu-154s did not have it. Later there were planes with the designations Tu-154A, then “A-1”, “A-2”, then Tu-154 B, etc. The latest modification with the designation "M". And everyone had this system. So why is one of the crew members in his last words scolds the flaps? I think at that moment he just realized that he had made a mistake,” the specialist said.

The expert notes that in this aircraft the switch for retracting and extending the flaps is located above the windshield of the cockpit. If the commander of the ship is piloting, then the second pilot releases the mechanization, and if the second pilot is piloting, then the commander controls the switch.

“There are grooves in the switch where the switch is locked in three different positions: “flaps-15”, “flaps-28” and “flaps-45”. And when the commander taxis on takeoff, he gives the command: “flaps-28.” . The co-pilot puts them in the take-off position. The plane (this, however, depends on the flight weight) takes off from the ground at a speed of 270-290 km per hour. Then, when it needs to cross a height of 120 m and go higher, it accelerates to a speed of not less than 330 km per hour and then a command is given to retract the mechanization. That is, from the “flaps-28” position, their switch is set to the “flaps-15” position. Meanwhile, the aircraft continues to accelerate. But there have been such cases - especially if the bumpiness is in air - when instead of "flaps-15" the switch was accidentally, by mistake, set to position "0". This, of course, is an assumption, but imagine: from "28" the flaps are immediately retracted to "0". And at the same time, the flight speed is at "clean wing", that is, when the mechanization has already been completely removed, is not provided. As a result, the aircraft reaches a critical angle of attack, at which a stall in a tailspin is possible. If something like this happened, then it can definitely be regarded as a crew error,” he emphasized.

Another expert described the possible situation on board the crashed Tu-154 somewhat differently.

“If the flaps begin to retract out of sync, then the point here is not that there is not enough lift force. There is enough of it. It’s just that the difference in lift forces on the left and right wings leads to the fact that the roll angle develops intensively. If you don’t react to this immediately, then nothing can be done further, since the speed increases and, accordingly, the difference in lift forces on the half-wings increases, and even the travel of the rudders is no longer enough to compensate. That is why all aircraft are equipped with mechanisms that limit the removal of mechanization if there is a mismatch. However, judging by according to the transcript of the negotiations, which appeared in the media, perhaps everything was even worse there: the pilots removed the flaps instead of the landing gear... And they were killed. In this case, there are no options at all..." he said.

Preliminary data from the transcript of the voice recorder of the Ministry of Defense airliner indicate that the plane lost control due to problems with the flaps and went into a critical angle of attack.

After rescuers managed to recover the voice flight recorder from the crashed Tu-154 of the Ministry of Defense from the bottom of the Black Sea, experts were able to decipher the recording stored on it. The film recording the crew's negotiations and conversations inside the cabin was not damaged.

The conversation is interrupted by one of the pilots exclaiming: “Flaps, bitch!” And then a cry sounds: “Commander, we are falling!” the source said.

When deciphering the black boxes, experts heard a characteristic signal from the system, which accompanies exceeding the angle of attack. This system automatically reacts to the critical angle of attack,” explained Life’s source.

The expert explained to Life that it is still premature to draw final conclusions about the causes of the disaster based only on snatches of phrases from the crew members.

This may be a subjective view on the part of the crew, which, however, is confirmed by the recorded sound of an automatic voice alarm, notifying the crew that the angle of attack has been exceeded,” says the expert.

In his opinion, the crew had some problems with the takeoff and landing mechanization during the climb. Flaps control the aircraft's vertical movement at low speeds. IN when released, they increase the lift of the wing.Flap position is important both during takeoff and landing. It is impossible to say yet what exactly the problems were with the Tu-154. Perhaps it was a mistake by the pilots when controlling the mechanization, or maybe it was unsynchronized cleaning of the mechanization.

Now we need to understand this,” says a Life source in the commission investigating the crash of the Ministry of Defense airliner. - IN the second recorder, parametric, has not yet been delivered to the Central Research Institute of the Ministry of Defense, and It is not yet known when decoding will begin.

As the vice-president of the Federation of Aviation Enthusiasts, Honored Test Pilot of the USSR Viktor Zabolotsky, explained to Life, if the plane has problems with the flaps, it may become uncontrollable.

It turns out that one wing has a large lift force, and the second one has a small one, naturally, the plane will turn over,” he noted. - If the flaps are not retracted or retracted unevenly, then very powerful heeling moments arise and it is very difficult to control the aircraft.

Test pilot Hero of Russia Magomed Tolboev also believes that Problems with flaps cannot just happen.

This is an aviation equipment failure. Failure to retract the flap or retract only one side leads to the destruction of the aircraft's half-wing. From the side from which they were fired, the plane stalls and loses speed,” Tolboev explained. - All this happens very quickly, and many pilots simply do not know what to do in such a situation. This applies not only to military pilots, but also to civilians.

According to Tolboev, when deciphering the black boxes, specialists heard a characteristic signal from the system, which accompanies exceeding the angle of attack. This system reacts automatically. Tolboev says, that the activation of this sensor is a serious signal for the crew commander.

It is triggered when there is a loss of speed or when the wing is at full load and the plane cannot lift any more, the expert explained.

Life's source in the Ministry of Defense says that the transcript of the voice recorder confirms the preliminary conclusions of engineers of the Scientific Research Center for Operation and Repair of Aircraft Equipment (SRC ERAT) of the Ministry of Defense about the causes of the disaster.

The crash occurred when the pilots were removing the mechanical equipment, and the plane was flying at a high pitch angle. As a result, he fell off the echelon during a maneuver to the right, says Life’s interlocutor.

One of the pilots of the Federal Air Transport Agency confirms the version of military aviation engineers.

The reason for the fall of the Tu-154 at this time point in the flight can only be a desynchronization of the flap retraction, the aviator told Life.

According to him, in the second minute of flight, the flaps are removed - the parts of the wing that control turns. At this stage, the automation may fail, then one of the flaps will remain raised.

This disrupts the aerodynamics so that the plane begins to twist towards the wing with the flap not retracted. It was possible to stop this situation if there was a headroom, but at the time of the tragedy the Tu-154 pilots did not yet have it, the pilot told Life.

Aviation expert Sergei Krutousov believes that it is necessary to wait for a complete decoding of both the voice and parametric recorder of the Tu-154, which records the operation of the aircraft’s components and assemblies.

Sergei Krutousov did not rule out the notorious human factor: when climbing, the pilots were unable to calculate the correct pitch angle.

When piloting while climbing in the control mode, the main difficulty lies in maintaining speed, which is stability when piloting and holding the aircraft in pitch at a climb speed of 500–550 km per hour, says expert Sergei Krutousov.

According to him, with a large positive pitch angle, when the airliner’s nose is raised, it could reach critical levels, lose lift and fall off the flight level.

An expert from the Federal Air Transport Agency says that a preliminary study of the voice recorder recording gives priority to versions of a technical malfunction of the airliner and pilot error. However, other versions are being developed. For example, foreign objects (for example, birds) entering the engine, low-quality fuel, resulting in loss of power and engine failure.

GVSU investigators who are investigating the disaster are also inclined to believe in the technical factor.

It is likely that the cause of the Tu-154 crash during climb could have been a failure of the aircraft’s hydraulic system, which led to the complete loss of the crew’s ability to control the aircraft. The cause of the failure of the aircraft’s hydraulic system could have been a short circuit in one of the aircraft’s engines, a source in the GVSU told Life.

Experts will be able to confirm or refute this version in the near future.

The Tu-154 disaster occurred on December 25, 2016 at 5:40 am Moscow time, 1.7 kilometers from the coast of Sochi. The plane of the Russian Ministry of Defense was flying to Syrian Khmeimim from the Chkalovsky airfield, and it was refueling at Sochi airport. There were 92 people on board the liner. Two minutes after taking off from the runway, not having time to gain altitude, the plane disappeared from the radar screens. The crew did not give any alarm signals.

Rescuers have already discovered the tail section of the Tu-154 with engines, as well as flight recorders and 14 bodies of the dead.

It seems that there is some clarity in the investigation into the causes of the Tu-154 crash in the Black Sea. Analysis of flight recorders and leaks from sources close to the investigation point to a problem that has very often led to mid-air tragedies: out-of-sync flap operation. It remains to understand who is to blame for what happened - the equipment or the crew.

By Tuesday evening, a preliminary analysis of the recordings of the black box of the Tu-154 that crashed on Sunday was completed. The version of an error in piloting technique is confirmed, an informed source reports. According to him, this follows from the analysis of the recorder data.

“We should have first removed them halfway after takeoff, and only after gaining speed – removed them completely. And the “right-winger” Filippov headlessly removed them in one fell swoop. And the plane crashed"

At the same time, earlier the media reported that the pilots reported problems with the flaps in the last seconds of the recording. In particular, one of the pilots exclaims: “Flaps, bitch!”

Earlier, test pilot Magomed Tolboev already said that the cause of the crash could have been problems with the flaps. According to him, in this case “the plane instantly turns around its axis.” “Neither the commander nor anyone has time to say a word, they are thrown there like herring in a barrel,” noted Magomed Tolboev.

Vice-President of the Federation of Aviation Enthusiasts, Honored Test Pilot of the USSR Viktor Zabolotsky clarified in a comment to Life that if there are problems with the flaps, the plane may become uncontrollable. “One wing has a large lift force, and the second one has a small one, naturally, the plane will turn over,” he said.

An Interfax source at the emergency response headquarters also reported that the Tu-154’s flaps operated inconsistently. Inconsistent operation of the flaps could, in turn, be caused either by technical reasons or by an error by the crew member responsible for their operation.

However, until the recordings of the remaining black boxes have been deciphered, experts do not know “where the crew’s hands were” - what the crew commander and co-pilot were doing at the fatal moment.

As experts explain, right in front of the co-pilot there is a lever for releasing and retracting the flaps. The commander gives the instruction: “Remove the flaps,” and the co-pilot does so. How exactly the crew acted will become clear later, but some conclusions can already be drawn.

Honored Pilot of the USSR, former Deputy Minister civil aviation USSR, President of the Civil Aviation Partner Foundation, who himself flew on the Tu-154, Oleg Smirnov, in a conversation with the newspaper VZGLYAD, emphasized that his first assumptions about the causes of the plane crash were also related to the flaps. The fact is that the plane disappeared precisely at the point in the flight where the flaps are retracted.

“The flaps extend from under the wing, increase its area and at the same time change the curvature of the flow. This is done to increase lift and reduce speed. The flaps are extended both before takeoff and during landing in order to perform it at a lower speed,” explained Smirnov.

Smirnov emphasized that the Tu-154 is equipped with automatic equipment, which, in the event of non-synchronous operation, stops the movement of the flaps. Usually the crew is not to blame for unsynchronized retraction of the flaps; this is solely the responsibility of the equipment.

“But if this audio recording appeared, it means that the automation did not work. This all happens so quickly that it leaves no hope of finding a split second to press the transmitter button and report what happened. The ship's commander gives the command to release. The flight engineer has one lever. He moves it, and the flaps go right and left. If the extension or retraction of the flaps occurs asynchronously, the automation should stop them,” he said, adding that deciphering the parametric black box, which records signals of mechanism activation and possible failures, will help clarify the causes of the crash.

“It happens that the equipment fails, the flaps can be retracted asynchronously,” another source of the Vzglyad newspaper, a former high-ranking military pilot, echoes Smirnov. “Then we must stop cleaning them right away!” Otherwise, the plane will simply fall to one side. I haven’t encountered this myself, but others have. Those who managed to stop cleaning are alive, those who didn’t have time were buried.” The interlocutor did not even rule out that the Tu-154 crew completely forgot to lower the flaps before takeoff.

The interlocutor cites as an example the death of the Tu-95RTs aircraft on January 25, 1984, the crew of which was headed by first-class military pilot Major Vymyatin.

“Took off from Olenya airfield on the Kola Peninsula. After 1 minute 55 seconds, during the climb at a speed of 346 km/h and an altitude of 350 m, the crew prematurely retracted the flaps at low speed, the source says. “There, you should have first removed them halfway after takeoff, and only removed them completely after gaining speed. And the co-pilot Filippov removed them in one fell swoop. The navigator told the commander to turn back on course. The commander put the car into a roll and brought the plane down. Everyone died. 92 tons of kerosene burned out for two days in a snowdrift. Something similar could happen here."

In the event of a pilot error, the question naturally arises about the qualifications of the crew.

Earlier it was reported that the commander of the crashed Tu-154, first class pilot Roman Volkov, had more than three thousand hours of flight practice. In this regard, conclusions were drawn that Volkov was an experienced pilot. However, Oleg Smirnov is skeptical about the figure of three thousand flight hours, calling it “cadet’s.” Smirnov himself has 15 thousand hours of flight time, including on the Tu-154. There are pilots with 20 thousand flights. Smirnov also recalled that each type of aircraft has its own characteristics. In addition, it is not clear from the flight time figures exactly how many flights the pilot made on this type of aircraft and in what capacity - aircraft commander, co-pilot, etc.

“If the commander flew all these thousands of hours on this plane, that’s one thing. And if on other types, then something else. Airplane and airplane are different. It all depends on its weight, size, placement of engines. Tu-154 is original in terms of aerodynamics. It has all three engines, each of which weighs more than a ton, in the tail, which means rear-centered. Aerodynamic forces work differently here. Each aircraft has its own characteristics, you learn them during retraining, and you always need to keep them in mind. In particular, when you retract the flaps, you need to behave very warily,” explained Oleg Smirnov.

Yuriy Sytnik, Honored Pilot of the Russian Federation, member of the Commission under the President of the Russian Federation for the development of general aviation, more than 20 years of experience flying the Tu-154.

On any aircraft, flaps are used to reduce the length of the takeoff run and the aircraft's mileage during takeoff and landing. The plane takes off at a speed of 700-900 km/h and lands at a speed of 280-220 km/h per hour, depending on the type of vessel. The Tu-154 lands at a speed of 260 km/h and takes off at a speed of 280 km/h. There is a command “Frontier”, “Rise”, the plane takes off. In order for the plane to take off at such speeds, the wing needs to be changed. For this purpose, there are slats and flaps. That is, they extend from the wing, increase its area, change the curvature, thereby increasing the lift force at a lower speed. But in horizontal flight such a swing is not needed, the passengers need to be transferred faster, the plane accelerates to a speed of 800-900 km/h, the flaps are already retracted. Everything is pressed compactly into the wing, and it becomes faster. The plane continues to fly at this speed. Then, when the plane descends and approaches the airfield area, again the flaps are extended first, then the landing gear. On the Tu-154, the flaps extend to 45 degrees.

Before takeoff, the flaps are extended on the runway. The plane taxis, the takeoff flaps are extended and set to 28 degrees. Then the plane increases engine operation, begins a takeoff run, lifts off the ground, retracts the landing gear, and when reaching a speed of 340 km/h and an altitude of at least 120 meters, the flaps are retracted. At what stage of the case with this TU-154 are we talking about flaps? Unclear.

And those who write that the flaps were released out of alignment are writing nonsense. If the flaps are misaligned, there is synchronization when the faulty flap stops, and the working one “works under it.” I have other information, for example, that the speed was 300 km/h, and we are not talking about the flaps, but about the strut (editor's note - the main power element of the aircraft landing gear). Something happened to the stand. Why did she stay on the ground and not in the sea? So did he touch the ground after leaving the runway? Dont clear. But I know that the stand was found on the shore. How did she end up there? She's heavy! It weighs more than a ton. How could she be thrown away? Is it a storm?

It is also unclear what height it was. If this height was 15-20 meters, then it is clear what it is. But if the height was 200 meters, this is a completely different option. We don’t yet know the true height; nothing can be said. If the height is 15-20 meters, then the crew made a mistake and, instead of retracting the landing gear, retracted the flaps at low speed, at a speed of 300 km/h. In this case, the commander lifts his nose so as not to touch the water, puts the plane into the second mode and falls into the water. And if, after a height of 120 meters, the flaps began to retract asynchronously, he simply turned over, and he was already in the water. But there is a system that controls this, this cannot happen. Then everything would have been different, the whole dynamics of the flight would have been different, it would not have fallen but gained its altitude. And here he is already lying one and a half kilometers from the shore. I think the flaps have nothing to do with it. I think that the crew did not work correctly. Who was sitting in the right seat - the co-pilot or the inspector? This is also the question.

On Tuesday, the main “black box” of the Tu-154 that crashed in Sochi was delivered to Moscow. The Life publication published a transcript, the authenticity of which was not officially confirmed, but it followed from it that the crew had problems with the flaps. And an Interfax source, in turn, said that the Tu-154 could have crashed due to a “stall” with insufficient wing lift for takeoff.

“According to preliminary data, the flaps on board operated inconsistently, as a result of their failure to release, the lifting force was lost, the speed was not sufficient to gain altitude, and the plane crashed,” said a source at the operational headquarters for work at the scene.

Novaya Gazeta asked experts to comment on the version with flaps.

Andrey Litvinov

1st class pilot, Aeroflot

— Flaps are very critical. We ( pilots — ed.) at the very beginning they assumed that these were flaps - as soon as it became clear that it was not fuel or weather. There were several versions - technical, pilot error. But it can be both. A technical problem resulted in a pilot error.

Flaps are needed only for takeoff and landing - the wing area increases, the lifting force increases, therefore, the plane needs a shorter takeoff distance than without flaps. You take off with the flaps, gain altitude, and the flaps retract. But they may not clean up if something is broken, or they may not clean up synchronously - one is faster, the other is slower. If they don’t clean up at all, it’s not a big deal; the plane flies on and on. He doesn't go into a dive. The commander simply reports to the ground that he has such a technical problem, returns to the airfield and lands - with the flaps extended, as required during a normal landing. And engineers are already figuring out what the problem is.

But if they are removed asynchronously, then the plane crashes, that’s what’s scary. On one plane of the wing the lift force becomes greater than on the second, and the plane begins to roll and, as a result, falls on its side. If the plane falls over, dives, and begins to lower its nose, the crew instinctively begins to pull the yoke towards themselves and increase the engine speed - this is absolutely normal. But the pilot must control the spatial position of the aircraft.
There is a concept - supercritical angle of attack. This is the angle at which air begins to escape from the wing. The wing becomes at a certain angle, its upper part is not flown around by air, and the plane begins to fall, because nothing is holding it in the air.

I flew the TU-154 for 8 years. I had no problems with the flaps, there were minor failures, nothing serious. It was a good reliable plane in its time. But that was 25 years ago. It is a product of its time. Aeroflot has all new planes - we fly Airbuses and Boeings. And the Ministry of Defense flies the TU-154. Yes, you need to make your own planes, yes, but at least let them take a superjet. Modern aircraft have a lot of protection systems; it is actually a flying computer. If some situation happens, the automation prevents the plane from stalling and is very helpful to the pilot. These same planes are all in manual mode, all in manual control. But this does not mean that it should fall, it must be technically sound. It must undergo maintenance. The question for the technicians is why such a serious breakdown occurred on this plane. Anyone can make a mistake. The crew does have experience, but military pilots generally don’t fly much. A military pilot flies 150 hours a year. And civilian - 90 hours per month.

Surprise could also have worked, they did not expect such a development of events, they did not have enough reaction to cope. This does not mean that they are inexperienced. Don't forget that the time was 5 am. Just sleep, the body is relaxed, the reaction is initially inhibited. We have been saying for a long time that we should ban night flights or reduce them to a minimum, we should strive to fly during the day, this is what many European companies do.

You also need to remember that the plane was heavy; the fuel tanks, cargo, and passengers were full. There was little time to make a decision. They didn't have time. This situation, of course, must be worked out. I don’t know how the army trains pilots, but here at Aeroflot it’s being worked out. There is an algorithm of actions for every emergency situation. Everything is endlessly practiced on the simulator. Did this crew go to the simulator when? If you were on the simulator, did you practice specific flap exercises? We are waiting for answers from the investigation.

Source close to the investigation

— Now the entire technical investigation is being conducted by the Ministry of Defense. This is a military aircraft - the Air Force Institute in Lyubertsy is engaged in deciphering the recorders, and all recorders, units, systems were transported to Lyubertsy. Flaps are not a critical situation, but in principle a controlled and manageable situation. There is an algorithm for actions in case of desynchronization or incorrect position of the flaps. Pilots are trained in everything, on simulators, including for every emergency situation flight crew practicing how to behave, how to fly an airplane. Each aircraft has its own specifics; algorithms have been developed for the Tu-154. A combination of technical problems and human factors can be assumed, but there is still not enough information.

Vadim Lukashevich

Independent aviation expert, candidate of technical sciences

— Failure to retract the flaps is not a disaster. This is a very unpleasant event, but nothing bad should happen from it. And in my opinion, a combination of circumstances and the actions of the crew led to the disaster in the Black Sea.

The essence of airplane flaps is to increase the lift of the wing at low speeds. How a wing works - the higher the speed, the greater the lift. But when the plane takes off, the speed is still low, the same as during landing. And in order to prevent the lift force from decreasing when the speed drops, the flaps in question are extended. You also need to understand that during takeoff the flaps do not extend as much as during landing. When the aircraft is taxiing on the runway, the flaps are already extended, and at the moment of takeoff, the landing gear is sequentially retracted, braking the aircraft, and after 15-20 seconds the flaps are also retracted, hindering the plane as its speed increases. In addition to lifting force, they also create additional air resistance and an additional diving moment - when the plane “wants” to lower its nose.

What happened at the time of the disaster? A heavy, loaded plane, filled with fuel, takes off, the pilots retract the flaps, but for some reason this does not work. In theory, you can continue the flight normally and in this state, without picking up speed, you can turn around and land to fix the problem. It is possible to land with the flaps in this position, but the landing speed will be higher and it will not be very easy. But obviously there was no such solution here. Perhaps the problem with the flaps was not noticed immediately, and when the plane began to lower its nose, words deciphered from the recorder may have been spoken.

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