本文件描述了民用飞机认证安全评估的指南和方法。它主要与显示符合FAR/JAR 25.1309有关。本文概述的方法确定了一种系统的方法，但不是唯一的方法，以表明合规性。本材料的一部分可能适用于非25.1309设备。介绍了飞机级安全评估的概念，概述了完成这项任务的工具。考虑了整个飞机运行环境。当飞机衍生产品或系统变更得到认证时，本文所述的过程通常仅适用于新设计或受变更影响的现有设计。在以新衍生产品实施现有设计的情况下，可使用服务体验等替代手段来证明合规性。

This document describes guidelines and methods of performing the safety assessment for certification of civil aircraft. It is primarily associated with showing compliance with FAR/JAR 25.1309. The methods outlined here identify a systematic means, but not the only means, to show compliance. A subset of this material may be applicable to non-25.1309 equipment. The concept of Aircraft Level Safety Assessment is introduced and the tools to accomplish this task are outlined. The overall aircraft operating environment is considered. When aircraft derivatives or system changes are certified, the processes described herein are usually applicable only to the new designs or to existing designs that are affected by the changes. In the case of the implementation of existing designs in a new derivation, alternate means such as service experience may be used to show compliance.