Changing the structure of the hierarchy of Russian air hubs in 1960–2023

High level of centralization of passenger transportation in the Moscow Aviation Hub is typical for Russia. It concentrates transit flows between regional airports. Unloading of the Russia’s main air hub is possible through the development of regional air hubs. The hypertrophy of the Moscow Aviation Hub is also due to the collapse of a unified aviation network of the USSR, the rudiment of which is the aviation network of the Russian Federation. Disconnection meant that the air hub system have lost the state of balance, i.e. the capability of a system to maintain its parameters through self-regulation. Now there is a restoration of balance within new state borders. It is advisable to develop air hubs based on the largest airports, which, by their stable position in the hierarchy of air hubs, ensure the balance of the entire system. The balance in the system of air hubs is described by the “rank–size” rule. To check the compliance of a hypertrophied system of air hubs in Russia with the rule the Yu.V. Medvedkov mathematical model is used. It makes it possible to estimate the proportionality of the Moscow Aviation Hub to the entire system (primacy co efficient), measure of contrasts between air hubs and determine the degree of deviation from their distribution in accordance with the “rank–size” rule. According to the methodology applied the rule was tested for the first time using the example of the largest airports hierarchy. The study is based on the data on passenger turnover of 30 largest airports of Russia for each year from 2013 to 2023 and on passenger departures from 30 largest airports of the USSR for each year from 1960 to 1981. The analysis shows that in 2013–2023 the Russian air hub system is close to the distribution in accordance with the “rank–size” rule – there is a tendency towards decreasing primacy coefficient of the Moscow Aviation Hub and decentralization. The changes occur mainly due to the growth of passenger turnover of the hubs in the upper segment of the hierarchy. The key factors of air hubs stability in the hierarchy are the territorial specialization and the transport and geographical position. In 1960–1981 the air hub system of the USSR was more polycentric and less contrasting. The similarity of the primacy coefficient values for the Moscow Aviation Hub in 2020–2023 and in the Soviet period, as well as a comparison of trends in the development of air hub systems suggest that the weakening of Moscow’s external ties contributed to the strengthening of ties between the next air hubs in the hierarchy. Thus, the formation of regional air hubs based on the largest airports in Russia aligns with the trends in the air transport system development.