The foreign real-time operating systems were widely used for the last years in Russia-developed aircraft as well as in the Russian Integrated Modular Avionics (IMA) research projects. But presently the question of their substitution with Russian analogues has arisen. This article provides the requirements of the operating system should satisfy in order to be used in the civil aviation, the analysis of existing foreign and domestic RTOS and some aspects of the operating system development process.(C)2017 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license