Moscow: Two days after Ukrainian President Volodymyr Zelenskyy cautioned civilian airlines about the dangers of using Russian airspace, numerous flight cancellations, airport closures, and other disruptions were reported across Russia.According to Radio Free Europe Radio Liberty, Ukraine's increasingly assertive drone campaign against Russia has been causing such problems for some time, and while no specific changes were immediately evident, Zelenskyy's indication that Kyiv was poised to escalate has raised questions about the potential extent of disruption for Russia. Valeriy Romanenko, from Ukraine's Museum of Aviation, expressed that the goal is not merely temporary disruption but to block operations around the clock, making Russian airports unusable. Romanenko suggested that such an operation is feasible and would require significant Russian air defense resources, while Ukraine would employ small drones for the task.The situation followed Zelenskyy's video address from September 1, where he warned eve ry airline using Russian airspace and other related entities that the Russian sky was becoming increasingly dangerous. Subsequently, Ukraine formally notified the International Civil Aviation Organization (ICAO) on September 2 about growing risks to civil aviation in Russian airspace.On September 3, disruptions were evident as Moscow's Vnukovo Airport temporarily suspended operations, and Sheremetyevo and Domodedovo airports announced restrictions. Moscow Mayor Sergei Sobyanin reported that 548 Ukrainian drones targeted the Moscow region between September 2 and 3. Russia's Transport Ministry responded by providing foreign airlines with clarifications on safety measures, emphasizing that significant disruptions would be avoided. However, Flightradar24 data indicated that four Russian airports were among the world's five most disrupted on September 3.Romanenko suggested that the strategy could involve targeting Russia's air-traffic-control infrastructure, including control towers and radar systems, without endangering civilian aircraft. Alexander Lanetsky, CEO of Friendly Avia Support, noted that paralyzing Moscow's airspace would significantly impact aviation across Russia, potentially declaring no-fly zones and affecting the entire aviation sector.Flight data from September 3 highlighted disruptions in domestic flights, underlining the economic impact in a country with 11 time zones. While much of Russia's international traffic, especially to Europe, has been canceled due to Western sanctions following the 2022 invasion of Ukraine, flights to countries like Turkey, China, and Egypt remain. Bohdan Dolintse, an aviation expert, stated that airlines flying to Russia will carefully assess threats, as any incident in Russian airspace would be Russia's responsibility.