As already mentioned in the previous part of the review, by the beginning of the 70s of the last century in our country, work on a fundamentally new radio-technical complex "Bumblebee", intended for AWACS aircraft of the next generation, entered the final stage. The radar, created at the Research Institute of Instrument Engineering (NII-17, now OJSC "Concern" Vega "), using the latest achievements of the domestic radio-electronic industry, was supposed to steadily detect and track air targets against the background of the earth.
After unsuccessful attempts to register "Bumblebee" on Tu-142 and Tu-154B aircraft and refusal to build a fundamentally new Tu-156, the customer, represented by the Ministry of Defense, tended to use the military transport Il-76. This aircraft with four D-30KP bypass turbojet engines with a thrust of 12,000 kgf was put into service in 1974. Although the flight characteristics of the Il-76 were somewhat inferior to the design data of the Tu-156, the use of the machine, which was in serial production and operated by the Air Force, simplified the development of the flight crew, removed many logistics issues and significantly reduced the cost of the program for creating the complex. The new AWACS and U aircraft based on the Il-76 received the designation A-50, or product "A". The program for creating a new generation aviation radar complex was launched in 1973 at the Beriev Design Bureau (now TANTK Beriev) in Taganrog.
Aircraft AWACS and U A-50
In addition to a centimeter range radar, a passive radio direction finding system and information display facilities, state identification equipment was included in the A-50 onboard equipment. The aircraft received a new special flight and navigation system, which provides automatic and semi-automatic flight control along a pre-programmed route. To process information about a large number of targets and their selection against the background of the earth, there is a digital computer complex based on BTsVMA-50 on board, which is also used in solving control and guidance problems for fighters. The processed information is displayed on the screens of operators in alphanumeric and plan views. It also displays data on the interceptor fighters interacting with the aircraft. If in the 60-70s, the long-range patrolling interceptors of the Tu-148 interacted with the Tu-126, then the Su-27P and MiG-31 were intended to work with the A-50.
Initially, these were color monitors on cathode-ray tubes. Trace processing of information about targets is performed by an onboard computer system using data from radar and other information sensors. It is possible both automatic tracking of targets along the trajectories of their movement, and semi-automatic, in which the operator begins tracking and adjusts the operation of the automation.
According to the views of the Soviet military leadership, the main task of the A-50 was the control and guidance of air defense fighters. In the automatic command mode, target designation can be issued to 12 interceptors, while radio guidance - to 30 fighters. The on-board guidance control system allows for all-round guidance of interceptor fighters of all types in service. Such a scheme of interaction was to be used in areas with insufficiently developed radar coverage. First of all, this applied to the Arctic zone, where, in the event of the outbreak of hostilities, a massive breakthrough by American strategic bombers - carriers of cruise missiles was expected. In addition to directing actions in the fight against air attack weapons, the air radar complex can withdraw front (naval) aviation to the area of ground (surface) targets.
At the request of representatives of the Air Force and Air Defense, based on the experience of operating the Tu-126, an automated system for active request-response and transmission of target designation commands and information to interceptors was created. On a telecode closed radio channel, all information from the aircraft could be transmitted to ground command posts. The range of operational radio communication in the shortwave range is 2000 km, and over the VHF radio channel and the broadband data transmission line - 400 km.
Even at the design stage, the exchange of data via secure satellite channels was provided. Navigation and communication antennas are located behind the cockpit on the upper surface of the fuselage. For objective control, there is equipment for documenting radar and flight information.
In order to counteract anti-aircraft and airborne guided missiles, an onboard complex for shooting thermal and passive radar interference is provided, as well as powerful REP stations installed in drop-shaped fairings on the sides in the nose and tail of the fuselage, in place of the defensive cannon installation of the military transport Il-76. The power supply of the very voracious onboard equipment is carried out from the AI-24UBE generator, with a capacity of 480 kW, installed in the landing gear fairing on the left side.
To eliminate the harmful effect of high-frequency radiation on the crew, a number of measures have been taken: all equipment posing a danger in this regard is shielded, and the side and upper windows of the pilot's cabin and the windows of the main and emergency exits are equipped with special metallized glass with a golden tint.
The crew of the aircraft is 15 people, of which 5 people are flight personnel, the rest are engaged in servicing the radio technical complex and communication equipment. The number of operators on the A-50, in comparison with the E-3C Sentry AWACS aircraft, is approximately two times less.
The rotating antenna of the radar "Bumblebee" with a diameter of 10.5 m and a height of 2 m is located on two pylons at the level of the trailing edge of the wing, below the tail stabilizer. That successfully solved the problem of aerodynamic and radio-technical combination of radar and tail. The radar fairing is made of two radio-transparent fiberglass sections and a metal caisson, in which, in addition to the main radar antenna, an antenna of the state recognition system is mounted.
The radar, which updates information every 5 seconds, has two main modes of operation: quasi-continuous and pulsed. The first mode is used to detect and track air targets, and the second is used to detect sea and ground targets. A mixed mode is also possible, in which several views of the quasi-continuous operation are alternated with the overview in the normal pulse mode with a high repetition rate. This allows simultaneous detection of both airborne and surface targets.
The processing of the radar signal is combined: at the first stage - using a discrete-analog device with quartz filters, at the second - using digital notches and Doppler filters. When working on low-altitude air targets against the background of the earth, Doppler filtering of the reflected signal is used to distinguish the mark from the target against the background of noise from the earth's surface. The radar computer carries out grouping by range elements of marks related to one target, measurement of azimuth and elevation, calculation of the unambiguous range to the target by marks at two or three repetition rates. And also the formation of information for displaying to the radar flight engineer and transmission to the on-board computer system, as well as automated monitoring of the technical condition of the radar equipment.
The heaviest part of the onboard equipment is mounted near the center of gravity, and the aircraft's center of gravity in flight changes in the same way as in a conventional transport Il-76, depending on the amount of fuel used. To improve pitch stability, large triangular aerodynamic horizontal ridges were installed on the chassis at the rear of the fairings. Since the cargo ramp is unnecessary for the AWACS aircraft, the hatch doors are sewn up with metal sheets. For refueling in the air, there is a refueling rod in front of the cockpit glazing.
The total weight of radio engineering, computing and communication equipment exceeded 20 tons. According to the characteristics of the detection range, the Bumblebee radar at the time of its creation was not inferior to the American AWACS system, and could detect a fighter against the background of the underlying surface at a distance of up to 250 km, and a target with an RCS of 1 m² - 200 km. The detection range of large high-altitude targets is up to 600 km. According to the Vega Concern, initially the equipment could track 60 targets. Later, thanks to the introduction of a more powerful computing complex, this parameter was brought to 150.
Although this is not the main purpose of the A-50 aircraft, the radar is capable of working on sea and ground targets. It is reported that the detection of large sea targets - up to the radio horizon, a column of tanks can be seen at a distance of 250 km. A number of sources say that with the help of optical means, launching ballistic missiles are visible at a range of up to 800-1000 km, depending on weather conditions and atmospheric transparency, but this option is most likely not available on most combat vehicles.
An aircraft with a normal takeoff weight of 190,000 kg (of which 60,000 kg is kerosene) could stay in the air for more than 9 hours and patrol at a distance of 1,000 km from its airfield, without refueling for 4 hours. The duration of one refueling patrol is 7 hours. Cruising speed - 800 km / h.
The first prototype of the A-50 took off in December 1978. The decision to start serial construction of new AWACS and U aircraft was made by the government in 1984. In the period from 1984 to 1992, taking into account three prototypes, 25 A-50s were produced. IL-76MD, built at the Tashkent aircraft plant (TAPO named after V. P. Chkalov), were ferried under their own power to Taganrog, where radar and other equipment were installed on them. In the same year, trial operation of one aircraft began at the Severomorsk-1 airfield near Murmansk. In 1985, the first A-50 of serial construction entered the 67th separate AWACS aviation squadron in Siauliai. The complex was officially adopted for service in 1989. At the same time, the 67th squadron was reorganized into the 144th separate air regiment. Then the regiment was relocated to the Berezovka airfield on the Kola Peninsula.
The first meeting in the air of the new Soviet AWACS complex with a NATO aircraft took place on December 4, 1987, when the Norwegian patrol P-3V Orion from the 333rd squadron crossed with the A-50 over the neutral waters of the Barents Sea. The Soviet vehicle received the designation Mainstay in the West. After the collapse of the USSR, all A-50s remained on the territory of Russia.
For the first time, the A-50s were involved in real combat operations in 1994 during the First Chechen War. In the highlands, they directed the actions of the Russian aviation, which was striking the bandit formations. Also, the A-50 was used during the "anti-terrorist" campaign in the winter of 1999-2000. and in hostilities against Georgia in 2008.
Aircraft AWACS and U A-50 and IL-18 at the airport "Ivanovo-Severny"
In August 1998, a separate AWACS regiment was relocated to the Ivanovo-Severny airfield, where it was transformed into the 2457th airbase for the combat use of early warning aircraft. The next reorganization took place during the "Serdyukovschina" - December 31, 2009.
The Ivanovo A-50 base became an aviation group for the combat use of long-range radar detection aircraft of the 610th Center for Combat Use and Flight Personnel Retraining of the 4th State Center for Aviation Personnel Training and Military Tests.
Satellite image of Google Earth: A-50 and A-50U aircraft at the Ivanovo-Severny airfield
According to Military Balance 2016, as of 2016, the Russian Aerospace Forces had 15 A-50s and 4 modernized A-50Us. According to the statements of representatives of the Russian Ministry of Defense, at least 9 aircraft are in a state of readiness for departure. Apparently, we are talking about machines capable of performing a combat mission. In the northeastern part of the airfield there is a parking lot, where, judging by the long absence of traffic, there are vehicles transferred for "storage".
Satellite image of Google Earth: A-50 in storage at the Ivanovo-Severny airfield
Aircraft AWACS A-50 in the past were actively promoted for export. In 1988, the export A-50E with simplified equipment was developed. On this machine, other state recognition and communication equipment was used, as well as means of classifying temporary resistance. This option was demonstrated to the chairman of the joint chiefs of staff of the Indian armed forces, Admiral Nadkarni. In April 2000, one A-50 was transferred to India on a short-term lease for familiarization purposes. The aircraft performed 10 flights from the Indian Chandihang airbase. The duration of the flights was 3-6 hours. The vehicle and the equipment were driven by a Russian crew, but there were Indian specialists on board. However, export orders for the A-50E with the Bumblebee radar did not follow, and subsequently, on the basis of the Il-76 for India and China, aircraft with foreign-made radars and communications were created, but these machines will be discussed later.
At the end of the 80s, the Baghdad AWACS aircraft was created on the basis of the Il-76MD with the help of French specialists. A Thompson-CSF Tiger-G radar antenna was installed on an Iraqi vehicle in a fixed fairing with a detection range of 350 km for fighter-type targets at medium altitudes. The first model was followed by a rotating radome aircraft known as the Adnan-2. Outwardly, it differed from the Soviet A-50 only in details - antennas of radio engineering systems and air intakes of air conditioning systems. In 1991, two Iraqi AWACS aircraft flew to Iran, fleeing the air strikes of the anti-Iraqi coalition, and the third was destroyed during the bombing at the airfield.
The AWACS and U A-50 aircraft embodied the most advanced achievements in the field of radio electronics and aircraft construction of the late Soviet period. But this car was not devoid of serious flaws. Although the working conditions of the crew were improved compared to the Tu-126, they still remained difficult. So, despite the need for a long stay on air patrols, there was no talk of a full rest for operators of radar and communication equipment. There was no toilet on the plane, and due to the strong noise, the operators were forced to work in special headphones with glycerin.
According to a number of domestic experts, the capabilities of the A-50 are still worse than those of the latest versions of the E-3 Sentry. Soviet equipment is one and a half times heavier than American equipment of a similar purpose. In addition, AWACS has the ability to target a larger number of fighters and the AN / APY-2 radar surpasses Bumblebee in detection range of high-altitude targets. However, the A-50 radio complex has an advantage in terms of the level of target selection against the background of the earth's surface, and with heavier equipment and insignificant superiority in detection range, one could put up with it, but the working conditions of the radio technical personnel could not be compared with the situation on aboard the Sentry.
Increased fatigue and the lack of conditions for normal rest, sanitary and hygienic procedures and food intake made the conduct of long patrols problematic. After 8 hours of being in the air with the radio equipment turned on, the operators often fell out of the plane, half dead from fatigue. After the collapse of the unified Soviet centralized air defense system and the loss of a permanent radar field over most of the country, the need for AWACS aircraft was enormous, and the A-50 was the only aircraft of this class in the Russian Air Force.
All this, as well as the fact that the element base of the on-board radar complex and communication equipment was largely outdated and did not meet modern realities, and the aircraft themselves needed refurbishment, led to the fact that in the 21st century, work began on the modernization of aircraft A that remained in service. -50. Work on an improved version, known as the A-50M (Product "2A"), started in 1984, simultaneously with the start of trial operation of the A-50. The reason for this was the shortcomings revealed during the tests and comments from the combat unit, where the experimental aircraft was operated. The main directions of modernization, in addition to the quite predictable increase in avionics' operating time between failures, was the installation of PS-90 engines and the improvement of the radio engineering complex in terms of improving the detection characteristics against the background of the earth and increasing the number of simultaneously tracked targets. At the same time, requirements were also made to increase the channels for the automated guidance of fighters. The navigation and flight complex and jamming equipment were also refined. The draft design of the new aircraft and the full-size model were ready already in 1984. For testing the radio technical complex, the already existing flying laboratory LL-A based on the prototype Tu-126, in 1987 was redesigned at the plant in Taganrog in LL-2A. At the Tashkent plant, a prototype A-50M was built, testing of which was planned for 1989. But in connection with the beginning of "perestroika" and due to lack of funds, work on the A-50M was stopped. Subsequently, the experience of installing PS-90 engines on this aircraft was used to create a new modification of the Il-76MF transport aircraft.
In the late 90s, it became clear that the existing A-50 aircraft fleet needed repair and modernization. When creating the A-50U version, the developments on the A-50M and the latest domestic achievements in the field of radio electronics were used. In 2009, it became known about the successful completion of factory tests of the first deeply modernized aircraft AWACS and U A-50U in Taganrog with the Shmel-2 radio complex. In 2012, the new aircraft, after passing trial operation in the troops and the completion of state tests, was officially adopted.
Satellite image of Google Earth: Il-76 and A-50U aircraft at the factory airfield in Taganrog
Compared to the A-50, the upgraded A-50U radio complex has improved capabilities for detecting low-flying and stealthy air targets (including helicopters and small-sized UAVs) with measuring their angular coordinates, speed and range. At the same time, the complex provides simultaneous control of the actions of several dozen fighters.
A-50U
According to data published in open sources, the complex's radar is capable of detecting a low-altitude fighter-type target against the background of the earth at a distance of 200–400 km, and high-altitude targets at a range of 300–600 km. Large sea targets are detected at a distance of up to 400 km. There are discrepancies in the sources regarding the number of simultaneously tracked targets. The maximum number of tracked targets is from 150 to 300. To detect the launch of TR and OTR, as well as SLBMs, an infrared rocket engine torch detection system can be installed on the upgraded complex, capable of detecting a rocket launch at a distance of up to 1000 km. The operational radio communication range on the KB channel is 2000 km, and on the VHF channel - 400 km. Information about air targets is transmitted to the central command post through repeater aircraft or ground intermediate points. In the absence of such an opportunity or during intensive combat work, satellite communications are used.
Automated workstation in the modernized aircraft A-50U
In the course of modernization, in addition to improving the characteristics of the radio engineering complex, great attention was paid to the working conditions of operators and flight engineers. The old CRT-based radar information displays have been replaced by modern color liquid crystal displays. Now on the plane there are places for rest, a kitchen and a toilet, which, of course, greatly simplifies the life of the crew during long patrols.
Recently, due to the aggravation of the situation at the borders, the need for long-range radar patrol aircraft has increased significantly. The Russian A-50 and A-50U take an active part in various exercises, where they invariably demonstrate high efficiency in detecting air and sea targets and in controlling the actions of military aviation.
But due to the high cost of operation and the limited resource of the not modernized A-50, there is no need to talk about regular control of our air lines by domestic AWACS aircraft. Unfortunately, A-50s are very rare guests in Eastern Siberia and the Far East, although it is there that they are needed most of all. As you know, in this direction, after the beginning of the "reform" of the armed forces, impressive gaps have formed in our radar field, and the entire Far Eastern Federal District is now covered by two fighter aviation regiments.
Satellite image of Google Earth: AWACS and U A-50 aircraft at the Elizovo airfield
One A-50 AWACS aircraft in September 2014 took part in major military exercises, during which long-range Tu-22M3 bombers and transport and tanker aircraft were transferred from the central regions of the country to the Far East. At the Kamchatka airfield Yelizovo, where MiG-31 interceptors are permanently deployed, Su-24M front-line bombers and Su-27SM and Su-35S fighters were also redeployed during the exercise.
Apparently, due to significant wear and a lack of financial resources, the entire existing fleet of A-50 aircraft will not be upgraded to the A-50U level. At the same time, great hopes are pinned on the new A-100 "Premier" AWACS aircraft. In November 2014, one Il-76MD-90A (Il-476), built at the Ulyanovsk Aviastar, was transferred to the TANTK im. G. M. Beriev for conversion into an AWACS aircraft of the A-100 type. According to the original schedule, the first aircraft was to be delivered to the customer at the end of 2016. Now we can say with full confidence that the deadlines have been disrupted, and this, however, is not surprising. One of the announced reasons for the failure to meet the deadline was the non-delivery of targeted radio visualization stations and the transmission of Igla control commands, for which the All-Russian Research Institute of Radio Equipment was responsible. In addition, the deadline for creating a secondary location system has been delayed by more than a year. The reason for the disruption in steel supplies is the poor development of design documentation and the constant change of design and management personnel.
The first flying laboratory A-100LL built on the basis of the A-50 for testing a new radar complex with AFAR took off only on October 26, 2016. According to the Izvestia newspaper, the promising radar of circular rotation, designated Vanta, will operate in four frequency modes, which must change all the time according to a random law. This is done to protect against interference and missiles aiming at the source of radio emission. According to the latest statements by representatives of the Ministry of Defense of the Russian Federation, the A-100 aircraft will take off in 2018. Reportedly, it should surpass all existing AWACS systems. But so far, neither the expected pace of construction, nor the cost of one A-100 aircraft have been announced.
Taking into account modern Russian realities, it can be assumed with a high degree of probability that, due to the high cost of the program, the supply of modern "air sentries" will not cover the need of the Russian Aerospace Forces in machines of this class. At the same time, from year to year, taking into account the growth of the characteristics of air attack means of "probable partners", the role of AWACS aviation is becoming more and more important. The solution to the problem, along with the operation of the existing A-50 / A-50U and the promising A-100, can be the creation of relatively inexpensive middle class AWACS aircraft of the E-2 Hawkeye dimension, high-altitude heavy drones with powerful radars and radar patrol balloons. In the past, in the USSR, attempts were already made to create relatively compact carrier-based AWACS aircraft, but this will be discussed in the next part of the review.
