The main flight software is essential for the correct execution of the flight's operations. It's made of a significant number of subroutines, being executed as soon as a damage occurs and which work together during the flight. According to the level of the damage and its time of appearance, the main program launches the safety subroutines which define the next stages and the issue of the flight.
Preparation before launching, Предстартовая подготовка (Программа ПСП):
Flight software, Программа полета (штатная программа):