Modernization of systems A-50 started by TANTK named after G.M.Beriev together with JSC «Vega Radio Engineering Corporation» in the late 1990s. It was designed to add new capabilities, such as reliable detection and tracking of low-flying helicopters, and integration of modern data exchange terminals for terrestrial users of the system. Combining target data from radar with electronic and radio intelligence to achieve more reliable target identification is another modernization task. Another task was to ensure the simultaneous operation of two or more A-50, with one aircraft as the master and the other as the slave, providing the master with a picture of the radar environment and providing guidance and air traffic control as assigned by the master A-50.
The A-50U test program took 5 years, with at least 800 test flights performed. On November 26, 2009, the Commander-in-Chief of the Russian Air Force, Colonel General A.Zelin, signed the Act of State Joint Tests of an Experienced A-50U.
The main emphasis in the modernization is on the transition to the new element base of the on-board radio engineering complex (RTC). This significantly reduced the total weight of the RTC and facilitated the aircraft. As a result, it was possible to take more fuel on board at the same take-off mass. Accordingly, the range and time of performance of the combat task at the specified turn have increased. Runway characteristics, stability and controllability of A-50U were left without changes. 
The new equipment contributed to increase in the detection range of the A-50 radar, while the number of simultaneously accompanied targets increased to 300.
The modernized radio engineering complex has improved capabilities for detection of low-flying and low-altitude aerial targets (including under conditions of active use of RAP devices) with measurement of their angular coordinates, speed and range. In addition, the radar provides detection of aerial target of helicopter type, as well as viewing of sea surface with detection of surface targets and measurement of their coordinates. In addition, new more powerful processors, along with new software, provide detection and tracking of aerial targets in the tail sector of the A-50 at a significantly greater distance than before.
The navigation complex includes a satellite navigation system, which allowed to significantly increase the accuracy of aircraft navigation.
The jobs of the members of the tactical crew of the aircraft have been radically modernized. Instead of older cathode ray tube-based hardware racks, the A-50U is equipped with universal display facilities based on display kits with liquid crystal indicators. The new computing system occupies just one rack of equipment, while the old one occupied at least seven. The A-50U satellite communication system has also been improved in terms of reliability, data rate and amount of information transmitted. The new anti-noise communication equipment has transformed the improved A-50 into a real combat control system.
Arrangement of instrument boards of operators, consoles and controls, volume and form of presented information, overview from workplaces, ease of working with equipment and its reach, quality and efficiency of signalling fully ensure operators in flight equipment performance of their duties. In addition, unlike the original A-50, the A-50U has rest rooms for the crew, a toilet and a buffet with household equipment.
The first A-50U aircraft was handed over to the Russian Air Force on 31 October 2011 (flight number 47, state registration RF-92957, manufacturer index 40-05). The aircraft was received by the Air Force crew and flew from Taganrog to the permanent location at Ivanovo airbase. The first A-50U reached full operational readiness in February 2012.
The second aircraft was ready in December 2012 (aircraft number 33, RF-50602, index 41-05). This А-50 was built in 1984 and came to carry out modernization works at the Beriev TANTK in early 2011.
The third modernized long-range radar detection aircraft A-50U handed over to the Russian Air Force on 25 March 2014. The aircraft A-50U with aircraft number 37 (RF-93966, 58-05) by the decision of the Minister of Defense of the Russian Federation was given the name of the famous aircraft designer, Deputy General Designer of TANTK named after G.M.Beriev Sergey Atayantz, who made a significant contribution to the A-50 and A-50U.
On December 7, 2016 at the factory airfield of TANTK named after G.M.Beriev the next serially modernized A-50U (No. 41) for Russian Aerospace Forces was carried out. In addition to the on-board number, this plane received its own name «Taganrog».
| № | f/n | p/n | s/n | reg. | date | modern. | handed | name |
| 1. | 47 | 0043453577 | 40-05 | RF-92957 | 1984 | 2009/11 | 31.10.2011 | |
| 2. | 33 | 0043454618 | 41-05 | RF-50602 | 1984 | 2011/12 | “Vladimir Ivanov” | |
| 3. | 37 | 0073476298 | 58-05 | RF-93966 | 1988 | 2006/10 | 24.03.2014 | “Sergey Atayantz” |
| 4. | 41 | 0083483499 | 63-05 | RF-94268 | 1988 | 2015/16 | 06.03.2017 | «Taganrog» |
| 5. | 45 | 0093493818 | 71-05 | RF-93952 | 1989 | 2017/18 | 06.12.2018 | |
| 6. | 42 | 0093484538 | 64-05 | RF-50610 | 1990 | 2016/18 | 28.03.2019 |
References and Credits:
- State tests of modernized A-50U completed / Vzlet 2010 01-02 /
- A-50: Heavenly eyes and ears of Russia / A. Mladenov /
- DRLO aircraft A-50U transferred to Russian Air Force / IA Weapons of Russia /