Federal Air Transport Agency: Russian aviation authorities initiate a protest over the situation with a NATO military aircraft 
by a course plane over the Black Sea from behind a NATO aircraft. This was stated by a representative of the Federal Air Transport Agency, RIA Novosti reports.
The Russian aviation authorities will transmit the protest through diplomatic channels. As the interlocutor of the agency emphasized, flights of military aircraft without radio communication carry risks to the safety of civil aircraft in the Black Sea region.
The increased intensity of NATO aircraft flights near the borders of the Russian Federation, including over the Black Sea, creates the risk of dangerous incidents in relation to civil aircraft
Representative of the Federal Air Transport Agency
The department also disclosed the details of the incident and confirmed that the Russian airliner, flying from Tel Aviv to Moscow, changed echelon because of the NATO CL600 reconnaissance aircraft. He performed a flight with an intensive descent from an altitude of 11,000 to an altitude of 9,200 meters, while crossing the routes of civil aircraft. The crew of the military vessel did not respond to repeated requests from the Russian airspace services.
What happened
The incident with a NATO military aircraft and a civilian airliner over the Black Sea took place on the morning of December 4. A US reconnaissance aircraft approached a passenger Airbus, which forced it to change direction to avoid convergence.
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According to the air services, there was less than 20 meters between the planes vertically, so the dispatchers gave the command to the civilian plane to descend 500 meters and take a safer echelon. Later it turned out that the evasion from the military plane had to be done at an altitude of ten kilometers. The press service of the Aeroflot airline confirmed that the order for the civil aircraft to change the flight level came from the dispatcher. It was due to the fact that “the trajectory was crossed by another aircraft.”
Intrusive flights
Recently, American reconnaissance aircraft have been making more and more flights in the Black Sea region. So, on December 3, Russian Su-27 and Su-30 fighters took to the air in order to prevent US military aircraft from violating the Russian borders. Russian Aerospace Forces fighters identified targets as the US Air Force RC-135 strategic reconnaissance aircraft and the US Army CL-600 Artemis reconnaissance and targeting aircraft.
In November, the Russian Ministry of Defense has repeatedly announced an increase in the intensity of aerial reconnaissance NATO countries near the Russian borders in the Black Sea. In particular, US Navy P-8A Poseidon patrol aircraft, US Air Force U-2S strategic reconnaissance aircraft and French C-160G Gabriel reconnaissance aircraft were spotted in the area.
After that, the Russian Foreign Ministry stated that the Russian military recorded flights of dozens of NATO reconnaissance planes and drones near the country's borders on a weekly basis. “NATO is purposefully testing us for strength by sending warships and aircraft to zones in the immediate vicinity of our borders, forcing Russia to react,” they noted. At the same time, all the measures that Moscow is taking in response to such provocations are adequate and restrained, the department stressed.