Based on the scenario analysis: the research of auxiliary power unit (APU) system requirement demonstration on high plateaus

When capturing the design requirements for civil aircraft, it is necessary to analyze them according to the requirements of ARP 4754A, based on the forward design principle of scenario combing. In this paper, the requirements for APU utilization are captured from the actual operation scenarios of civil aircraft at high plateaus in China[1]. For example, the utilization of APU needs to take into account the impact of plateau environments on its performance, such the altitude to start up on the ground and the altitude to provide bleed air,etc.[2-3] Different from plain aircraft, when operating at high plateau, APU s are usually used in takeoff and approaching phases to supplement engine thrust to obtain the performance gain.This article provides scenarios for using the APU during normal aircraft operation scenario and system failure scenario, and demonstrates the APU ground start height and air supply and bleed air height indicators based on the characteristics of high-altitude airports in China.