The article considers the process of cooperation between the ATC and airport operation services. The analysis considers the procedures of cooperation while inspecting a runway before performing flights, aircraft departure and arrival that encompass the entire range of coordinated operations. For each procedure, the costs of aircraft delays are calculated. The assessment was carried out by synthesizing the chronology of services cooperation in real conditions. On the basis of the collected data flowcharts of services cooperation to ensure flights of an airport and the ATM services were built. To provide a visual comparison of the existing and proposed model sof services cooperation the networks of services cooperation were built based on the mathematical model of the graphic chart. The operation network establishes the sequence of events to provide departure of one aircraft operating a scheduled flight of an airline. Within the given study the ATC service and the aerodrome service are involved to ensure a departure. Cooperation between the operation and dispatch service of the airport and an aircraft crew is conditional because in this case they do not impact the technology of cooperation. The network is a particular set of dots(summits)interconnected by lines (links). In the case of our study, circles are events (performed work). Directional segments (lines) are work connecting events to each other. While assessing the process of cooperation during arrival and departure, two cases were considered: the runway is occupied or clear.The runway could be occupied for different reasons: available vehicles, people, animals or flocks of birds on the runway. The study of the cooperation technology was carried out for 12 monthsof making scheduled flights at Zhukovsky and Ostafievo airports on the basis of every day flight plans.

In the process of performing a complex of works on refueling of civil aviation aircraft, one of the key issues is to ensure flight safety by controlling the quality of aviation fuel directly during refueling operations. Currently, to ensure the purity of the refueled jet fuel, water separators with filter elements of a normalized degree of purification are installed on the aircraft refueling facilities, the operation of which in the working area provides normalized indicators of cleaning jet fuel from water and mechanical impurities. As practice shows, in the process of refueling aircraft, for various objective and subjective reasons, sometimes there are stochastic situations in which quality indicators go beyond the limits established by regulatory documentation and are not deterministic, and the subsequent state of such a system is described by values that characterize an extremely low level of jet fuel purification with negative consequences for flight safety. This paper presents a mathematical description of the functioning of water separator filters in the working area, where standardized indicators of the quality of aviation fuel are provided during the refueling of aircraft. The article deals with the issue of blocking the refueling of aircraft in the event of the appearance of non-normalized technical documentation indicators of the quality of aviation fuel, which arise due to a number of different factors that lead to negative cause-and-effect relationships for flight safety. Based on the mathematical description, an approach to creating a system for protecting and blocking the refueling process under the working name "Barrier" is proposed. Of the greatest interest for the study are typical water separator filters installed on refueling vehicles as terminal technical devices for fuel purification during refueling of aircraft.

The article covers the problem the multidimensional routing of flights for the transportation of cargo and mail, with the condition of the corresponding equipment presence for performing navigation of increased precision to obtain the possibility of the formation flights under any weather conditions. The given circumstances are capably essential to reduce load while using the airspace, which will make it possible to achieve transportation independent of its saturation. While planning the routes it is also necessary to consider the interests of different interested groups, which are often opposite to one another. In the view of the different directivity of the tasks in question, the solution can require the sorting as excessively as large, so the smaller quantity of possible situations (versions of the solution), the lower the level of the calculation of these versions is, and the greater their quantity is. The exact example of multidimensional routing, which is affected by the interests of operational nature and the interests of the urgency of the performance of the claims, expressed by weight coefficients, is depicted in this work. The only version in favour of the general production process, which is obtained with the help of a genetic algorithm, is a solution of this problem. It was necessary to introduce some designations and assumptions, the enumeration of which can be supplemented. Optimal solution can be obtained both by the enumeration of the solution versions and with the help of the genetic algorithm, which is allowed for a smaller number of iterations, to obtain suboptimal in real time, which corresponds to the conditions of the task solution. In that the example dynamic priorities are assigned, based on multiplicative form by expert evaluation, which form criteria for the ranking of request for each step of route planning. As a result, there are the exact versions of the solution, which correspond to the interests of different groups and the version, obtained with the help of a genetic algorithm, which satisfy the opposite interests of these groups. All versions of the solution are proved to be different, which indicates the need of applying the objective and substantiated apparatus for making the decision, which the genetic algorithm actually is. The proposed mathematical apparatus has prospects for implementation.

The development of the aviation transport system is characterized by sophistication of interacting objects, the multi-criteria nature of the tasks to be solved and difficulties in making management decisions. For example, modern medium haul aircraft are fitted with up to 25,000 sensors to monitor the performance capabilities of functional systems components. Numerous ground-based instrumental methods and means of diagnosing the technical condition are used. This requires the development of methods and algorithms for determining and monitoring the criteria of limiting state of the monitored components and functional systems of aeronautical equipment. In this regard, analytical models of predictive estimate for the technical condition of aeronautical equipment, determination of aircraft maintenance modes and provision of spare parts and materials become essential. The paper proposes a scheme of the aircraft fleet maintenance system modeling algorithm and deducing the mathematical model of the optimal number of aircraft states in order to exclude secondary and subjective factors. The method of statistical modeling based on Markov processes with discrete states and continuous time is the basis of the proposed analytical model. The proposed method is reduced to the synthesis of some modeling algorithm of the investigated process that simulates the complex system components behavior and interaction as well as random perturbing factors. A distinctive feature of the presented algorithm is determination of the predominant estimated dependences of transition probabilities and intensities taking into account the requirements of the modern regulatory framework in terms of reliability of equipment and diagnosing the technical condition. The analysis of the predominant estimated dependencies study results in the conditions of operation of the aircraft maintenance system confirmed a high degree of correlation of the time duration effect on the particular states in order to diagnose the technical condition depending on the diagnostic concept. The proposed simulation model can be used for the aircraft technical condition predictive estimate, aircraft gas turbine engines and functional systems.

The paper examined the possibility of improving the energy efficient performance of an electric tiltrotor with a lift-propulsion propeller group for a steady flight mode by reducing the energy consumption of the propeller group per unit of time or per unit of the path traveled by the electric tiltrotor. This is achieved by selecting the optimal tilting angles of the electric tiltrotor total thrust vector. In the proposed approach, the trimming tilting angle of the propeller group is variable, depending on the aerodynamic characteristics of the electric tiltrotor, its propeller group. Since the propeller group is equipped with the drives for tilting them, this approach is easily implemented by the conventional facilities of the electric tiltrotor. The tilting of the total thrust vector, on the one hand, leads to an increase in the effective value of the aerodynamic lift coefficient and, on the other hand, it is accompanied by a decrease in the projection of the total thrust vector on the flight speed vector, a change in the drag and power required to create the thrust of the propeller group. This circumstance makes it necessary to solve the optimization problem in order to increase the maximum endurance and long-range capabilities in the cruise mode of the electric tiltrotor flight. The paper presents a method for calculating the optimal tilting angles of the total thrust vector based on the equations of steady motion of the electric tiltrotor in the cruise flight mode, the expression for the total power required for the rotation of the propellers of the propeller group. The analytical dependences for the optimal tilting angles of the total thrust vector are obtained depending on the ratio of the wing area to the total propeller-disk area of the propeller group and the aerodynamic quality of the electric tiltrotor.

The article investigates the problem of hydro-elastic interaction of a weak shock wave with a rigid nosed rotation shell preloaded with axial forces. The shell is enclosed in a rigid parabolic screen, i.e. the impact of the end face and the shock wave diffraction are not considered. Liquid is regarded to be perfectly compressible. Its applied summing hydrodynamic pressure during complex interaction with the shell surface can be classified into the incident, reflected and radiated waves. The problem of hydro-elastic interaction of these shock fronts with a preloaded parabolic rigid nosed shell in a related setting is reduced to the solution of the wave equations of nonlinear system of equations for shell motion under particular initial and boundary conditions, in which the dimensionless displacement of this nose section under the impact of hydrodynamic forces is determined by integrating its motion equation. The equations, describing the dependences of nose section displacements on shock wave interaction time, take into account generalized hydrodynamic forces, including the second category directly related to the mass of the attached fluid. Determination of stress-strain state in case of interaction with the shock wave in the liquid of elastic rotation paraboloid in the form of the shell containing a rigid insertion in the nose section is reduced to the solution of a nonlinear equations system of shell motion considering the boundary conditions along fastenings at the end face of the shell and interface conditions of the shell and insertion. Dimensionless displacements of the nose section caused by hydrodynamic forces are defined by integrating the equations of motion under the initial conditions along insertion offsets in the axial directions.