Beriev A-50

infobox Aircraft
name = A-50 Shmel
type = AWACS
manufacturer = Beriev

---

caption =
designer =
first flight = 1978
introduced = 1984
retired =
produced =
number built = around 40
status = In service
unit cost =
primary user = Russian Air Force
more users =
developed from = Ilyushin Il-76
variants with their own articles = KJ-2000

The Beriev A-50 Shmel ( _ru. Шмель 'bumble bee'), (NATO reporting name: Mainstay) is a Russian airborne early warning (AEW) aircraft based on the Ilyushin Il-76 transport. Developed to replace the Tupolev Tu-126 "Moss", the A-50 first flew in 1978. It entered service in 1984, with about 40 produced by 1992.

Development

The decree of the Central Committee of the Soviet Union Communist Party and the USSR Council of Ministers of 1973 ordered the Taganrog Machine-building Plant (now Beriev company) to develop the A-50 AWACS aircraft, based on the Ilyushin Il-76M transport and fitted with the Shmel radar system. [Flying Radars - From the history of Russian Airborne Early Warning and Control Systems, Air Fleet Magazine, Issue 35, 2003]

Since the new A-50 aircraft featured unrivaled capabilities in the USSR, insofar its sophisticated avionics, powerful electric sources, liquid and air-cooling systems were concerned, the design bureau's experts faced a host of technical challenges, which either had never been addressed before at all, or had been of a considerably smaller scale.The fact that the aircraft was fitted with a great number of powerful transmitters and highly sensitive receivers, quartered next to one another, made it a must to solve the problem of electromagnetic compatibility, which was later on successfully resolved on a full-size mock-up.In order to provide stable operation of avionics and high reliability of the system proper, given considerable heat release, designers developed unmatched air- and liquid-cooling systems, as well as automated systems, facilitating their operation.A special electric power system, boasting high current characteristics, was designed to power the on-board radar system.

Considerable efforts were aimed at adjusting and fine-tuning the Shmel radar system. Its separate components were tested on the LL “A” flying testbed, manufactured by the Taganrog Machine-building Plant and based on the first Tu-126 prototype. The flying testbed made its maiden flight in Taganrog on 15 August 1977.

When developing the A-50, designers carried out considerable research and development to provide the platform, fitted with a large rotating radome, with sufficient aerodynamic characteristics and stability. As a result, aerodynamic performance, stability, and controllability of the new aircraft turned out to be only slightly different from those of the baseline Il-76M aircraft. In order to increase the A-50's flight endurance, it was decided to fit the aircraft with an air-refuelling system.

The lion's share of modifications, introduced into the baseline military transport, when it was converted into the AWACS aircraft, was caused by the necessity to accommodate new avionics and other equipment, facilitating its operation.In compliance with the new role of the aircraft, the aft cargo hatch and the portside door were welded up, while every piece of transportation rigging was stripped off. The tail gun mount was replaced by the electronic equipment compartment. The satellite communications aerial fairing was mounted right in front of the wing centre section.The Shmel radar system was housed inside the fuselage, with the radar transmitter being quartered in its rear part. In order to protect the crew from microwave emissions, the rear fuselage was separated from the rest of the aircraft by a screen, while the windows were equipped with metal-coated glass. The radar aerial was fitted inside a rotating radome with a diameter of 10.2m and two metres thick. The air-intake of the equipment cooling system was housed in the tailplane root.

The Shmel radar system comprised the following components:
*a 3D Pulse-Doppler radar;
*data display equipment;
*an active interrogation-reply and command transmitting system;
*digital computer;
*IFF system;
*command and control equipment;
*communications equipment;
*datalink equipment, etc.

Operators' automated workstations were fitted with colour CRT displays, which displayed alphanumeric and panoramic data. They also displayed data on interceptors, cooperating with the AWACS aircraft.

The A-50 AWACS aircraft was operated by a crew of 15: a five-man strong flying crew and a 10-man strong mission crew, including chief operator (radar system commander), navigators, tracking operators, and flight engineers.

The Taganrog Machine-building Plant completed converting a series production Il-76M military transport, built by the Tashkent Aircraft Plant, into the first A-50 prototype in 1978, while on 19 December of the same year a flight crew, headed by Vladimir Demyanovsky, took it for its maiden flight. The first flights were conducted without the radar system. After the radar system had been installed, the A-50 was submitted for joint official tests.
From December 1978 until October 1983 the Beriev company converted a total of two series-produced Ilyushin Il-76Ms and one Il-76MD, which participated in the joint official tests. The first A-50 (aircraft A-1) was used to test flight characteristics and radar system support systems. The second prototype (A-2) tested the radar system proper and the new Punktir integrated flight and navigation system, while the third one (A-3), which became the pattern aircraft for series production A-50s, became the testbed for the ECM suite and special equipment. The most crucial stage of the tests was held at the NII VVS Soviet Air Force Scientific Research Institute in 1980-85 (now the Akhtubinsk-based
GLITs Russian Air Force State Flight Test Centre named after Valery Chkalov).

In December 1984 the authorities arrived at a decision, based on the test results, to launch the A-50 AWACS aircraft into series production at the Tashkent Aircraft Plant (now the Tashkent Aircraft Production Corporation, TAPC). In 1985 A-50s started to enter service alongside Tu-126s. The A-50 AWACS aircraft, fitted with the Shmel radar system, was officially fielded in 1989. By that time the 67th separate AEW squadron was reorganised into the 144th separate AEW regiment.

By the time the USSR broke up, the Tashkent Aircraft Plant had manufactured approximately two dozen production A-50s, fielded with the 144th separate AEW regiment, deployed at an airfield outside the Lithuanian town of Siauliai, and later on transferred to the Berezovka airfield near Pechora town in northern Russia, when the Baltic states declared their independence. At the present time the regiment has been transformed into the AEW aircraft airbase, deployed since 1998 outside Ivanovo. Another 20 A-50 AWACS aircraft, fitted with the Shmel radar system, were to have been produced in Tashkent by the mid-1990s, and then the plant was to have shifted to manufacturing upgraded A-50Ms with improved Shmel-2 radars, but these plans had never been fulfilled due to the break up of the USSR and the economic recession in the post-Soviet Russia.

Design

The A-50 is intended to perform the following missions: detection, tracking and IFF determination of air and surface targets, surveillance, command, control and communication functions for command posts and automatic control systems, guidance of fighter aircraft to air targets and to surface targets.

The mission personnel of the 15-man crew derive data from the large Shmel surveillance radar with its antenna in an over-fuselage rotordome, which has a diameter of 35 ft 5 in (10.8m).

The A-50 is capable of flying for 4 hours at a 1000 km from its base at a maximum takeoff weight of 190 tons. The aircraft can theoretically be refuelled by Il-78 tankers, although flight tests showed that aerial refueling was all but impossible because the rotordome would hit turbulence from the tanker, causing severe buffeting. [ [Ilyushin IL-76, Russia's Versatile Airlifter, Aerofax] ]

The A-50 can control up to 10 fighter aircraft.The Shmel radar is capable of tracking up to 50 targets simultaneously within 230 kilometers. Large targets, like surface ships, can be tracked at a distance of 400 km.

Operational history

Until 1990 A-50 aircraft had pulled routine duty, occasionally participating in large-scale training exercises of the Soviet Armed Forces and joint exercises with armed forces of the Warsaw Pact member-states. In the winter of 1991 as Operation Desert Storm unfolded in the Persian Gulf, a pair of A-50s, flying over the Black Sea, tracked combat aircraft of the allied coalition, delivering air strikes on Iraq from the Turkish territory.

In late 1994 the A-50 went into harm’s way during the suppression campaign in the North Caucasus. Three A-50 AWACS aircraft were transferred to the operational airfield in the North Caucasus. They provided uniform radar coverage of the battlefield by constantly being in the air. On 21 December 1994 Russian Air Defence forces established complete control over Chechnya's airspace after almost a three years' break. Joint patrol missions, flown by A-50s and Su-27 and MiG-31 interceptors, prevented Chechens from establishing an air route with foreign friendly nations. A-50 aircraft also discharged similar tasks during the anti-terrorist campaign in winter 1999-2000.

Modernisation: A-50M and A-50U

Given experience, acquired during the tests and the initial operation, deep modernisation ofthe A-50 AWACS aircraft and its radar system started as far back as the mid-1980s.

The decree of the Central Committee of the Soviet Union Communist Party and the USSR Council of Ministers dated 9 January 1984 ordered the Beriev company to develop an upgraded A-50M aircraft, fitted with the Shmel-2 radar and powered by the D-90 engines (now known as the PS-90A). The new radar system, being developed by MNIIP, the flagship enterprise of the Vega Scientific Production Association, was to provide a greater detection range and magnification of the targets tracked, as well as to feature a capability of guiding more fighters to the targets. In addition to the new radar system the platform proper, its integrated flight and navigation system, and ECM suite were also considerably improved.

The draft design of the new A-50M aircraft (product 2A) was developed as far back as 1984, and its mock-up was built the same year. In order to test the new radar, the new LL “2A” flying testbed, based on the LL “A” (Tu-126), was built in 1987. The Tashkent Aircraft Production Corporation started to build the A-50M prototype, which was to undergo tests in 1989. The flight tests over, about three dozen production A-50Ms were planned to have been produced by the turn of the century.However, as fate would have it, the plans had to be considerably revised. An economic crisis had become apparent by the late 1980s, and the development of the new radar system was no longer properly funded. As a result, the A-50M project, just like a number of other promising projects in the sphere of combat aviation, was terminated in compliance with the decree of the USSR Council of Ministers dated 22 October 1990. Production of the first A-50M in Tashkent was stopped, while the LL “2A” flying testbed was ferry-flown to the LII Flight Test Institute, where it had been stored on the outskirts of the airfield, until it was scrapped (participants in the first Mosaeroshow and MAKS air shows, held in the early 1990s, could easily see it standing there).

Instead of the A-50M the Russian Air Force decided to develop a cheaper A-50U AWACS alternative with the advanced Shmel-M radar system providing a twofold increase in the number of tracked targets and guided fighters, and boasting a greater detection range. A mock-up of an aircraft like that was built in 1990, while in 1993 a production A-50 started to be converted into a prototype of the new AWACS aircraft. The A-50U was expected to have commenced flight tests in 1995 with subsequent retrofitting of operational A-50s to its level. However, due to insufficiënt funding, development of the advanced radar system has so far failed to reach the flight tests stage.

A-50 for export

The project, aimed at developing A-50 export versions for potential foreign customers,has seen greater progress than the internal Russian modernisation program.

China’s A-50I

Russia and Israel secured the first contract on joint development of the A-50I AWACS aircraft, to be fielded with China, at the Le Bourget air show on 17 June 1997. Under the contract, signed by the Rosvoorouzhenie State Enterprise (now Rosoboronexport) and Beriev company and the Israel Aerospace Industries (IAI), Beriev was tasked with developing a platform to be fitted with a Israeli-produced radar system.The A-50I aircraft (where “I” stands for Israeli) was based on the production A-50, stripped of Russian avionics and upgraded to mount the EL/M-2075 Phalcon radar (where Phalcon stands for Phased Array L-band Conformal Radar), developed by Elta Electronics, affiliate office of the IAI. This radar can track 60 targets simultaneously up to 370 km away for targets with a radar cross section of 3 square metres.

In the course of converting the A-50 into the A-50I the following modifications were introduced:
*the aircraft was fitted with the fixed mushroom-shaped radome with a diameter of 11.5m (the A-50 features a rotating radome with a diameter of 10.8m, while the US E-3A features a radome with a diameter of 9.1m), and pylons for the new radome; the radome design envisions housing three EL/M-205 Phalcon radar phased arrays, forming a triangle;
*the fuselage design was improved;
*the operators' cockpit and the rest room were quartered in the pressurised part of the fuselage; the aircraft was equipped with racks for housing the Phalcon radar units, operators' workstations and resting places;
*the aircraft was modified to accommodate a five-man strong flying crew, ten avionics operators, and nine by-crew members;
*the aircraft was fitted with an emergency hatch for the operators to bail out;
*the rear fuselage design was improved and ventral fins were mounted to provide the aircraft with directional stability;
*the airframe mounted 71 antennae, including 44 aerials of the Phalcon system;
*the nose and the rear fuselage, as well as wingtips were modified to quarter antennae of the electronic systems;
*electric power, liquid- and air-cooling, air-conditioning, oxygen supply, communications, and other systems were modified.

The A-50 was converted into the A-50I in 1997-99, and on 28 July 1999 a flight crew headed by test pilot Gennady Kalyuzhny took the aircraft for its maiden flight off the factory airfield in Taganrog.A total of 15 test flights and seven training flights had been carried out during the tests. The tests conducted proved that the aircraft met all the requirements, specified by the customer, and on 26 October 1999 the A-50I was ferry-flown to Israel to be fitted with the radar system and tested.A total of four aircraft were to have been fielded with the Chinese Air Force, but in summer 2000 under a most powerful political pressure from the USA the Israeli government suspended the contract. In 2001 new Israeli prime-minister Ariel Sharon officially informed China of the contract's being reneged on. It remains unclear how much penalty payment Israel paid to China. The only A-50I ever built was parked for some time in a fenced-off area of the Ben Gurion airport. After being stripped off its Phalcon radar and electronic systems the A-50I airframe was handed over to China via Russia in 2002. Out of this airframe China finally developed its own KJ-2000 AWACS aircraft.

A-50E/I

India was the first to express its interest in an AWACS aircraft, based on the A-50, as far back as 1988.In 1988 A-50 AWACS aircraft fitted with the Shmel (Bumblebee) radar system was shown to Indian specialists to possibly consider purchases of these aircraft. The proposed variant of the A-50 did not suit the Indian Air Force, since it failed to interact efficiently with India’s air defences and provide target designation to their contemporary fighters. As a result, New Delhi decided on developing an indigenous AWACS system to be based on the Avro 748 transport produced locally under British license. Two HAL-748 AWACS demonstrators were manufactured in the second half of the 1990s. After one of them had crashed, the IAF suspended the program and again turned to the A-50 option.Under a December 1999 agreement, the Russian Air Force assigned one A-50 to India for familiarisation flights. The aircraft arrived at Chandigarh airfield, Punjab State, in April 2000. A Russian crew was joined on board by Indian specialists to perform ten flights, up to 6 hours each. The Indian party was left generally satisfied with the aircraft’s performance.Russia offered India the modified A-50EI variant with the Israeli-made radar system that much more corresponded to India’s expectations. In 2001 India ordered three A-50EI AWACS aircraft. The first aircraft was scheduled to arrive in 2007-08 but has been delayed.

Following the interest and purchase of 6 A-50's by India, Beriev and MNIIP embarked on developing a dedicated export version of their AWACS aircraft, designated A-50E (where “E” stands for export). Depending on the customer's requirements, the aircraft may be fitted with the Russian Shmel radar system, developed by MNIIP, or the Israeli Phalcon radar. The A-50E aircraft are to be built by TAPO (Uzbekistan) with the assistance of Beriev (Russia) according to production forms and records, developed by the Ilyushin Aviation Association, with the new AWACS aircraft based on the series production Il-76TD, fitted with more sophisticated and powerful PS-90A engines.

Variants

* A-50M - Modernized Russian Version [ [http://en.rian.ru/russia/20080910/116681254.html Russia modernizes fleet of A-50M AWACS planes] ]
* A-50U - updated Russian variant
* Il-976 (Be-976 or SKIP) [http://www.vectorsite.net/avil76.html#m6] - (СКИП - Самолетный Контрольно-Измерительный Пункт, Airborne Check-Measure-and-Control Center) - Il-76/A-50 based Range Control and Missile tracking platform. Initially built to support Raduga Kh-55 cruise missile tests."Has fixed radar cover filled with other equipment and glassed navigator cockpit.
* A-50I - variant with Israeli Phalcon radar, designed for China but project cancelled under pressure of United States
* A-50E/I - export version with Russian Shmel or Israeli Phalcon radar
* KJ-2000 - Chinese variant based on the A-50I airframe

Operators

; RUS
* Russian Air Force - 16 in service; USSR
* Soviet Air Force
* Soviet Anti-Air Defence; IND
* Indian Air Force - 6 ordered

pecifications (A-50)

aircraft specifications
plane or copter?=plane
jet or prop?=jet
ref=
crew=15
capacity=
payload main=
payload alt=
length main=49.59m
length alt=152 ft 8 in
span main=50.50 m
span alt=165 ft 6 in
height main=14.76 m
height alt=48 ft 5 in
area main=300 m²
area alt=3,228 ft²
airfoil=
empty weight main= 75,000 kg
empty weight alt= 374,000 lb
loaded weight main=
loaded weight alt=
useful load main=
useful load alt=
max takeoff weight main= 170,000 kg
max takeoff weight alt= 374,000 lb
more general=
engine (jet)=Aviadvigatel PS-90A
type of jet=turbofan
number of jets=4
thrust main= 157 kN
thrust alt= 35,200 lbf
thrust original=
afterburning thrust main=
afterburning thrust alt=
engine (prop)=
type of prop=
number of props=
power main=
power alt=
power original=
max speed main= 800 km/h
max speed alt= 500 mph
cruise speed main=
cruise speed alt=
stall speed main=
stall speed alt=
never exceed speed main=
never exceed speed alt=
range main= 6,400 km
range alt=4,000 miles
ceiling main= 12,000 m
ceiling alt= 39,360 ft
climb rate main=
climb rate alt=
loading main=
loading alt=
thrust/weight=
power/mass main=
power/mass alt=
more performance=
armament=
avionics=

External links

* [http://www.vectorsite.net/avil76.html#m6 vectorsite.net Beriev A-50]
* [http://www.spyflight.co.uk/mainstay.htm Spyflight.co.uk - Beriev A-50 Mainstay]
* [http://www.aviation.ru/Il/#A-50 Aviation.ru A-50]
* [http://www.red-stars.org/spip.php?article67 Red-stars.org - A-50 Mainstay]
* [http://nvo.ng.ru/armament/1999-11-26/6_avaks.html Source article of NVO (in Russian)]
* [http://www.military.ir/modules.php?name=News&new_topic=0&pagenum=27 Iranian AWACS (in Persian)]

References

Related content

Related development:
Ilyushin Il-76

Comparable aircraft:
E-3 Sentry

Designation sequence (Beriev):
A-40 -A-50 -
A-60

Designation sequence (Ilyushin):
Il-76 -
Il-78 -
Il-80 -Il-82 -
Il-86 -
Il-87 -
Il-96