基于运行场景的民用飞机低油量告警分析

Operating scenario-based fuel level low alarm analysis of civil aircraft

油箱内可用燃油量在驾驶舱显示是民用飞机燃油系统的重要功能之一,飞行员应在整个飞行过程中知悉油箱内的可用燃油量。正常情况下,燃油箱内的可用燃油量应可支持飞机抵达目的地,如果可用燃油量不足以支持飞机飞抵目的地,将被视为不安全状态。通过分析CCAR-25部、FAR 25部、CS-25部中关于低油量告警的设置要求,和CCAR-121部中对航空公司/飞行员宣布“最低油量”的要求,引入民用飞机设置低油量告警的必要性和低油量告警阈值计算原则。基于民用飞机运行场景,以某干线民机为例计算两种场景下的低油量告警阈值,并经过分析得到最终的低油量告警阈值,提出飞机触发低油量告警后飞行员操作建议,可为民用飞机燃油系统开展低油量告警的需求分析提供参考。

The display of available fuel quantity in the cockpit is one of the important functions of the civil aircraft fuel system.Pilots should be aware of the available fuel quantity throughout the entire flight process.Under normal circumstances,the available fuel in the fuel tank should be sufficient to support the aircraf's arrival at the destination.If the available fuel may not be sufficient to support the aircraft's arrival at the destination,it will be considered unsafe.This article analyzes the requirements for setting fuel level low alarms in CCAR25,FAR25,and CS25,as well as the requirement for airlines/pilots to declare"minimum fuel"in CCAR121.It introduces the necessity of setting fuel level low alarms in civil aircraft and the principle of calculating alarm thresholds.Based on the operational scenarios of civil aircraft,carry out two calculation methods and factor analysis for fuel level low warning thresholds in"waiting"scenarios.Taking a three tank civilian aircraft as an example,calculate the low fuel alarm threshold for two scenarios,and after analysis,obtain the final low fuel alarm threshold.Propose pilot operation suggestions after the aircraft triggers the fuel level low alarm,which can provide reference for the requirement analysis of fuel level low alarm in civil aircraft fuel systems.