Justification of Boeing 777 Flight Crew Actions in the Conditions of Complicated Navigation Situation

The main aviation accidents and incidents related to Air Data Inertial Reference Unit failures are considered. A comparison of the Boeing 777 Navigation System structure with one of III generation long-haul aircraft was made, with the indication of differences that justify the impossibility of applying previously developed methods to the Boeing 777 Navigation System. The paper deals with the shortcomings of the methods used in Computer-Based Training and Quick Reference Handbook are analyzed and more advanced action methods are developed, which are recommended to be included in the QRH and Airline Flight Operations Manual and justification of Boeing 777 flight crew actions at various stages of the navigation system failure.