本SAE航空航天推荐规程（ARP）确定并定义了测量影响直升机动力装置可用装机功率的因素的方法。这些因素包括安装损耗、附件功率提取和运行影响。在计算RFM中描述的直升机性能时，准确确定这些因素至关重要。本文提出的方法旨在规定和定义每个因素以及测量所述因素的方法。仅考虑直升机涡轮轴发动机的基本安装。虽然所述方法原则上可适用于导致更复杂安装损失的其他配置，例如入口颗粒分离器、入口屏障过滤器（带或不带旁路系统）或红外抑制器，但在这些情况下，可能需要专门或单独的技术来确定和定义发动机安装损失。 一些旋翼机可能会使用另一种推进系统电源来补充发动机输出轴的输出功率。如果RFM性能包括补充动力装置（SPU）的贡献，则还应定义和测量SPU的可用装机功率，本文件中描述的功率损耗系数和方法可能适用。

This SAE Aerospace Recommended Practice (ARP) identifies and defines a method of measuring those factors affecting installed power available for helicopter powerplants. These factors are installation losses, accessory power extraction, and operational effects. Accurate determination of these factors is vital in the calculation of helicopter performance as described in the RFM. It is intended that the methods presented herein prescribe and define each factor as well as an approach to measuring said factor. Only basic installations of turboshaft engines in helicopters are considered. Although the methods described may apply in principle to other configurations that lead to more complex installation losses, such as an inlet particle separator, inlet barrier filter (with or without a bypass system), or infrared suppressor, specialized or individual techniques may be required in these cases for the determination and definition of engine installation losses. Some rotorcraft may use an alternate source of propulsion system power to supplement engine output shaft power delivered. If RFM performance includes the contribution of a Supplemental Power Unit (SPU), then the installed power available of the SPU should also be defined and measured, for which the power loss factors and methods described in this document may be applicable.