“…The average age of passenger aircraft of aviation companies engaged in commercial air transportation is 14.6 years, of which mainline passenger aircraft are about 11 years old, regional passenger aircraft are 31 years old, including the most popular types of aircraft A321neo, A320neo -2 years, A321, A320 -11 years, A319 -17 years, A330 -12 years, B737-800, B737-900 -10 years, B737-700, B737-500, B737-400, B737-300 -22 years, At the end of 2021, aviation industry enterprises supplied 83 aircraft to the foreign and domestic markets, of which 32 airplanes and 51 helicopters, 851 aircraft engines for civil and military purposes [11][12][13].…”