Difficult take off Su-35
In February of this year, the first Su-35S began to arrive in the 23 th Fighter Aviation Regiment (IAP) of the 303-th Mixed Air Division of the 3-th command of the Russian Air Force and Air Defense on the Dzemgi airfield in the Khabarovsk Territory. The success of the new aircraft seemed to be obvious. Only here, past the attention of the media, there was a return from the 929-th State Flight Research Center (GLITS) named after Chkalov in Akhtubinsk six sides of the issue 2012 of the year. The United Aircraft Building Corporation (UAC) also kept silent about this in their press releases.
The organization of the transfer of fighters to the Air Force is not entirely clear to specialists. According to the regulatory documents, the 4 Training Center for Aviation Personnel (CPA) in Lipetsk, but not the combat regiment, should be the first to receive machines for the development of a combat training program and a manual on combat use. It is worth recalling that the development of another newest fighter - Su-30CM went according to a regulated scenario. The first products arrived in the Lipetsk center last year, and this year two front-line "thirty" flew to the air base in Transbaikalian Domna.
The experts did not understand too much why the Dzemgi airfield was chosen as the location of the Su-35. Not only the 23-iap station is stationed there, it is also the factory airfield of the Kagolsky-on-Amur Su-35 Komsomol aviation production association (KnAAPO) named after Gagarin. It is surprising and the fact of receipt of the aircraft in the Air Force combat units. After all, he is formally in the development work and, according to UAC, will be released to state trials only in 2015 year.
In an informal setting, many specialists - avionics developers express their complaints about the onboard equipment of the "thirty-fifth", in particular, they speak about the unreliable operation of air pressure receiving systems. It is often even described as “flightless.” What is actually happening with the newest fighter, what are its problems and prospects?
Algorithms of Discord
On the website of the company “Avtopribor-Voskhod”, which is a part of OJSC Concern “Radioelectronic Technologies”, in the section “Combat Aviation” the VSP-35 system is indicated without an abbreviation of the abbreviation. In the on-board equipment of the Su-35, it is responsible for measuring the altitude-speed flight parameters. The unique product, superior to Western competitors in some indicators, turned out to be the Achilles' heel of the newest fighter and the cause of the conflict between the Central Aerohydrodynamic Institute named after Zhukovsky (TsAGI) and the defense industry enterprises.
SI VSP-35 should replace the usual receivers of air pressure (LDPE), standing in the nose of the aircraft, in the very center of the radome fairing.
“The system not only measures pressure, but also, using the data obtained, calculates the barometric altitude required for separation, the Mach number, the true and instrumental velocity. That is, all the aerometric parameters needed by the pilot, ”an aircraft engineer who participated in the development of the device told the Military Industrial Courier newspaper.
According to him, similar products are on most modern combat aircraft, including so far the only fifth-generation serial fighter - the American F-22 "Raptor".
“This is not a tribute to fashion, but a technically sound decision. For optimal operation of the onboard radar station, it is necessary, firstly, to maximize the radio transparency of the fairing, and secondly, to remove the front “patch” of a conventional LDPE, which closes the radar's front field of view and breaks its diagram. Therefore, the receivers are removed into the depths of the aircraft, ”added a senior official at the Sukhoi Design Bureau on condition of anonymity.
For the first time, such a system was attempted to be implemented in the mid-80-ies on the Su-27M, which are now living on Kubinka. The second attempt was the "Indian" Su-30MKI, but the aircraft manufacturers, faced with difficulties, decided to abandon it in favor of the usual nose LDPE. And now the third approach to the problem.
It is important not only to measure the pressure, but also to calculate the aerometric parameters from the data obtained. Further the most difficult begins. The received data is transmitted to a special calculator, where the recalculation is carried out according to the most complicated algorithm using mathematical filters. But the work on the algorithm from the very beginning went wrong.
“We needed field studies. The system is mounted on a reference aircraft with standard instruments of traditional design in order to calibrate it and collect empirical material. We need to perform a lot of test flights in order to clean up the algorithms, ”says the source of the MIC.
If the very "iron" SI VSP-35 developed "Aerribor-Sunrise", then the algorithm prescribed TsAGI. Employees of this institute, having “blown through” the model, suggested the optimum location for the sensors.
“The algorithm has calibrations that need to be constantly refined during flights, seeking to reduce errors to the required level. And it is very important that the test machines are the same. The slightest change in the location of the hatches, antennas, etc., leads to a change in the flow around them. But Su-35 rolled out to the next "party congress". Because of this, there was no time to understand the algorithm, there was no time to wait for its refinement, and all three participants in the testing of the aircraft were very different from each other. For example, on the Su-35 with the 902 tail number, the left and right sides are generally different, ”the source continued.
According to another aircraft engineer, the Sukhoi Design Bureau refused the services of TsAGI, prescribing its simpler algorithm for motor automation, only to lift the car into the air.
“They were immediately warned that nothing good would come out and we would have to return to complex mathematics. With the Sukhoi algorithm, it is possible to teach an airplane to fly a “pancake”, but difficult maneuvers, supersonic flights and the use of weapons is impossible, ”he noted.
In 2008, the first Su-35 with a unique system and algorithm developed by the Sukhoi Design Bureau took off. According to a high-ranking representative of one of the military-industrial associations, it was impossible to integrate the VSP-35 SI and the electronic brains of the development of the design bureau.
Aeropribor ships the equipment, rents it to the technical representative. "Dry" all gathered, put on the plane. Turned on and said: your device does not work, go modify. And what to refine, if the algorithm is unknown to the manufacturer of "iron"? - He complained.
The source noted that the peak of the problems came in December last year, when they began to hand over a batch of combatant Su-35С for the domestic Air Force. “Everyone was sitting in Komsomolsk-on-Amur, they shot the VSP-35 SI, put it on the stand, checked it. The devices worked, but when they were put on board and sewn, everything stopped working. The system manufacturers immediately demanded that the UAC gave the final firmware, at least the necessary drivers. We have no idea what they wrote there. One device burned out altogether, ”he says indignantly.
According to him, a system similar to SI VSP-35 works perfectly on the newest Ka-52 combat helicopter: “There are no complaints about the algorithm and equipment, the products are already on production machines. Previously, the helicopter instruments began to testify only at 50 speed per kilometer per hour. Now, as in a computer game, even the speed of one kilometer per hour is shown. But for Su-35, UAC chose to independently pursue higher mathematics. ”
The Sukhoi Design Bureau does not deny that there were big problems with VSP-35 SI, but they claim that they have now been resolved.
“We received a certificate for the product and software late last year. Of course, now it is easy to say that it was necessary to do this in such a way that the algorithm is not complete. But at that moment there was a need to raise the plane, and TsAGI for each correction required a lot of time and not too little money. We will take into account that the work on Su-35 is being financed due to a commercial loan obtained from a bank, and not under state guarantees, ”explained a high-ranking official of the OKB.
He added that the design engineers themselves had prescribed the algorithm. Now “Sukhoi” still ordered the work of TsAGI, but, as the interlocutor noted, for the distant future: “Since 2008, we have collected empirical material, improved the algorithm. Now we want to experiment with the installation of the sensors themselves. The locations proposed by TsAGI turned out to be suboptimal. We now have an aircraft laboratory for such research. We are in the ROC for another two years and only in 2015 will we go out on state tests, so there is time. ”
Happy end?
“For a long time, our air forces could not afford modern aircraft and limited themselves only to upgrading the existing aircraft. Now the task is to update the entire aircraft fleet as quickly as possible, but this cannot be resolved by traditional methods, ”said the officer of the Air Force Main Committee, participating in the Su-35, told“ MIC ”.
According to him, while preparations are underway for the transfer of aircraft 23-iap, pilots of the Sukhoi Design Bureau, 929-th GLITs and 4-th CPA are developing a primary program.
“Transmission is not easy. For the time being, we will put the boards on record in the technical-operational part, we will check all the documents, a training manual for the pilots will be ready. There is nothing complicated. Takeoff-landing, en-route flight and simple aerobatics. Elements of interception are possible, ”he explained, and noted that six of those who returned to the Su-35 plant last year will be upgraded. These vehicles, released in 2012, were not involved in test flights, but pilots from the 4-CCP received the first tolerances for them.
“It was decided to make the main aircraft look 2013 of the year. Of the six upgrading sides, four this spring will go to the 4-th CPA to practice a more complex program of combat training and instruction in combat use. And when Lipetsk finishes work, the Dzmega pilots will already master the primary program, ”the officer said.
It is noteworthy that the Su-35 will be transmitted in a gray-blue camouflage, tested on the Su-30CM in Transbaikalian Domna, instead of the “eggplant” that has become familiar in several years.
In general, the plane went out of the bad luck and ceased to be "flightless." Employees of the OKB did everything they could, showed high professionalism, having essentially lifted up a complicated and promising car for the money, achieved quite good results. But story Su-35 shows all the problems that worsen every day the already not the best relationship between industry producers and developers.
“Su-35 was the first sign of the scheme, in which Mikhail Pogosyan instructed the board to be integrated not to the specialized enterprises that were doing this, but to himself (that is, KLA. - Approx.“ MIC ”). Sukhoi created a specialized unit and began to design it himself. The company used to deal with the general development of the aircraft, the fuselage design, strength things, and then engaged in mathematics, ”said the representative of the military-industrial complex.
The current global trend in aviation production is the “integrate integrable” rule. Developers write algorithms themselves and connect subsystems. Airbus, Lockheed Martin and other giants act as the final packer, stitching together ready-made systems into a single board. But in Russia, due to departmental ambitions, specialized institutes, design bureaus with many years of experience and work culture, formed over decades, often turn out to be thrown out of cooperation.
The development of modern aircraft does not allow haste. F-35 team chief of test pilots, Lieutenant Colonel Hank Griffith, back in 2011, commenting on the slow pace of progress of the flight program at the speed reached, said: "We are moving forward with childish steps to make sure our aerometric system meets our expectations." Apparently, the United States is not rich enough to save on the quality of flight tests and product development.
The history of the Su-35 is very instructive. It would seem impossible to imagine that the newest fighter is being developed and produced under a commercial loan. But even last December 29, Prosecutor General of the Russian Federation Yury Chaika, in his speech, indicated that the UAC leadership provided enterprises with interest loans in the form of loans for the construction of civil aircraft of domestic production, instead of donating them to the authorized capital of companies.
All the interlocutors of the publication noted one important fact. If now we do not establish effective scientific and practical cooperation between aircraft manufacturers, manufacturers of engines, instruments, avionics systems, etc., then the funds allocated for the PAK FA will go nowhere, and the work will drag on for an indefinite time. If at the level of development engineers there is mutual understanding and respect, then the CEO and other top managers prefer to act, as the audit by the prosecutor general’s office shows, disregarding the obvious expediency, making profit at the highest price at any price. In this situation, I would like to wish the developers and manufacturers of aviation products to finish their work and deliver reliable and modern machines to the Russian Air Force.
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