Забезпечення статичного балансування легкого транспортного літака під час зміни його маршових двигунів

Abstract

The process of improving the existing aircraft fleet through the development of modifications has become widespread in both domestic and foreign aircraft manufacturing. Under modern conditions, no country in the world is capable of simultaneously modernizing all types of aircraft. Economic and scientific-technical resources are usually directed toward developing those types for which there is the greatest demand. Limiting the number of types in conjunction with developing modifications for existing aircraft significantly contributes to increasing the efficiency of the entire air transport system. Objectively, there are several reasons for modifications in transport-category aircraft. The first reason is associated with increasing discrepancies between technical and economic indicators. The second reason is related to the use of this type of transport in practical human activities, which is progressively expanding. The third reason is the influence of time. Creating modifications allows to a certain extent to resolve the contradiction between the deadlines for creating complex modern technology, which have increased, and the accelerated pace of scientific and technological progress. The subject of this study is the process of ensuring static balancing of a light transport aircraft during the replacement of its propulsion engines. The goal is to develop models for ensuring the static balancing of a light transport aircraft (LTA) in conditions involving changes in its propulsion engines and reconfiguring the lifting surface system while minimizing the aerodynamic quality costs for balancing changes in the LTA. Tasks: Determine the process of ensuring static balancing of transport category aircraft considering the coefficient of static stability degree; peculiarities of applying this coefficient in balancing a LTA; establish the correlation between the coefficient of static stability degree and the aerodynamic polar of a balanced LTA; quantitatively evaluate and minimize the losses of wing aerodynamic quality to achieve static balancing of the LTA. The obtained scientific results enable both the balancing of a LTA and the minimization of aerodynamic quality losses. Conclusions: Based on the obtained dependencies and their numerical analysis, it has been established that when replacing the engines of a light transport aircraft with a payload capacity of 9.1 tons, the coefficient of static stability of 0.15 complies with the requirements of the Airworthiness Standards for Transport Category Aircraft. During the numerical analysis, it was also determined that for such an aircraft, the aerodynamic quality losses amounted to 7%–9%, which is acceptable for the considered aircraft type.