The simulation model of the airline is the imitation of the process of operating the aircraft depot of the airline with the aid of computer. It gives the possibility to control the running efficiency of the aircraft depot under the specific conditions of the airline.

Any airline can be examined as the complex discrete system in which occur the events interacting with each other in the time and the space. Flight schedule is comprised, aircraft take off, carry out flights, return to the base, are being maintained, etc.

The simulation model of the airline makes it possible to carry out experiments with the program model on computer instead of carrying out experiments with the real system.

The following quantitative and qualitative factors are input for the simulation model:

• periodicity of planned maintenance, duration of planned and nonsystematic maintenance;
• organization of maintenance (the capacity of production shops, the qualification of personnel, the organization of work);
• flight schedule and characteristics of routes;
• the indices of reliability and operational technological effectiveness of aircraft;
• the enumeration of minimum equipment;
• organization of supply with spare parts.

The simulation of the process of operating the aircraft on the computer makes it possible to define the dependence of operating characteristics of the airline, such as the average number of delays to 100 departures, average flight time to the listed aircraft and the operating costs, on the factors, enumerated above. Change in the values of the assigned parameters and also introduction of the additional parameters, which consider the conditions of concrete airline, makes it possible to obtain the quantitative assessment of effectiveness in the work of the airline.

The simulation is applied in the JSC “Ilyushin Aviation Complex” for the estimation of the expected running efficiency with the design of aircraft IL-96-300 and IL-114 and also for estimation and analysis of the results of operating the aircraft IL-62 and IL-86 in concrete aircraft enterprises. With the aid of the imitation simulation was conducted the quantitative assessment of the expected effectiveness in the separate measures, such as increase in the periodicity of separate forms of operational and periodic maintenance.

For the concrete airline the base simulation model, including the modules of ground handling, flight operations and flight schedule, is being completed under the actual conditions of applying the aircraft depot of the assigned airline.

The simulation model makes it possible:

• to select the most suitable version of the organization of system;
• to investigate the behavior of system in any situations;
• to repeat and to change experiments many times;
• to economize cash resources without resorting to experiments with the real system.

The simulation model of the airline makes it possible to solve the following types of tasks:

• The volume of transportation is assigned (routes, flight schedule).
         To determine the required number of aircraft and the necessary parameters of the system of ground handling for guaranteeing the transportation with the permissible degree of the risk of the program implementation.
• The volume of transportation (flight schedule) and a quantity of aircraft is assigned.
        To determine the necessary parameters of the system of ground handling for guaranteeing the transportation with the permissible degree of the risk of the program implementation.
• Тhe volume of transportation (flight schedule), a quantity of aircraft and the system of ground handling is assigned.
        To determine possible organizational, technical and financial measures for guaranteeing the transportation with the permissible degree of the risk of the program implementation.