The Beriev A-50 Shmel (Russian: 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.

The mission personnel of the 15-man crew derive data from the large Liana surveillance radar with its antenna in an over-fuselage rotordome, which has a diameter of 29 ft 9 in (9.00 m).

The A-50 can control up to 10 fighter aircraft for either air-to-air intercept or air-to-ground attack missions. 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 be refuelled by Il-78 tankers , although some sources indicates flight tests showed that aerial refueling was all but impossible because the rotodome would hit turbulence from the tanker, causing severe buffeting.

The radar "Vega-M" is designed by MNIIP, Moscow, and produced by NPO Vega. The "Vega-M" 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.

   * A-50M - Modernized Russian Version fitted with mid-air refueling capability.
   * A-50U - updated Russian variant
   * Izdeliye-676 - One-off stop-gap telemetry and tracking aircraft.
   * Izdeliye-776 - One-off stop-gap telemetry and tracking aircraft.
   * Izdeliye-976 (SKIP) - (СКИП - Самолетный Контрольно-Измерительный Пункт, Airborne Check-Measure-and-Control Center) - Il-76 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, (One prototype and five production conversions).
   * Izdeliye-1076 - One-off special mission aircraft with unknown duties.
   * 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

General characteristics

   * Crew: 15
   * Length: 49.59m (152 ft 8 in)
   * Wingspan: 50.50 m (165 ft 6 in)
   * Height: 14.76 m (48 ft 5 in)
   * Wing area: 300 m² (3,228 ft²)
   * Empty weight: 75,000 kg (165,347 lb)
   * Max takeoff weight: 170,000 kg (374,786 lb)
   * Powerplant: 4× Aviadvigatel PS-90A turbofan, 157 kN (35,200 lbf) each

Performance

   * Maximum speed: 800 km/h (497 mph)
   * Range: 6,400 km (3,977 mi)