Abstract
Lately, the leading countries of the world paid more attention to their critical infrastructure cyberdefence. Civil aviation is not an exception. In this area, modern information and communication technologies are widely implemented, so it generates a whole range of new vulnerabilities and potential threats. Known models allow formalizing processes of creating a complete set of requirements (according to relevant guidance documents) that should be done to ensure civil aviation cybersecurity and identifying their execution. However, the issue of fullness assessment of requirements fulfillment remains unresolved. In view of this, in this work a method of estimation is developed, which gives ability to determine the quantitative parameters, that characterized fulfillment of complete set of requirements for civil aviation cybersecurity and differentiated requirements of control authorities in accordance to defined cybersecurity model. This method can be used for fullness evaluation of requirements fulfillment for providing cybersecurity and in other sectors of the critical infrastructure of the state. Later, based on this method, it is planned to develop a software application to support decision-making on expert evaluation of fullness requirements fulfillment for civil aviation cybersecurity.