According to the requirements of “Rules for Operational Qualification and Certification of Public Air Transport Carriers of Large Airplanes” （CCAR-121-R8） and Advisory Circular called “Operation of Plateau Airports”,the route adaptability analysis of plateau routes mainly includes drift-down analysis and oxygen supply analysis. In this paper,drift-down analysis and oxygen supply analysis for SR-VIKUP flight segment are carried out,which is a typical case of long distance,high altitude,few alternative airports,and high frequency of use operated by Boeing 787-9 aircraft. This paper firstly analyzes the regulatory requirements and influencing factors of the drift-down procedures and cabin depressurization procedures for plateau routes,and determined the calculation parameters. Secondly,it calculates the route performance after one engine failure,followed by obstacle clearance analysis based on the feature that the large pulsed oxygen system of the Boeing 787-9 model can flexibly configure the descent profile according to the terrain,in combination with the minimum safe altitude of the flight segment. Finally,according to the temporary re-routing needs in operation,the emergency procedures for drift-down after the failure of one engine and the emergency procedures for cabin depressurization are optimized. This study has solved a major difficulty in operation control in this area,and is of positive significance to the operation of other impulse oxygen system models and similar plateau routes.