RF航段衔接ILS进近程序的最大下降角设计方法

RNP 程序的RF 航段与传统ILS 精密进近程序相结合能充分利用两类程序的优势，但两种程序的过渡阶段需要考虑最大下降角度的设计。本文分析过渡阶段程序的平面与剖面几何设计参数限制条件，以及从星基导航方式转为陆基无线电导航方式需要稳定截获航向信号与下滑台信号的运行限制条件；结合两种限制条件，设计一种可以从不同最后进近定位点（FAP）高度计算下滑道的偏离量与到最后航向截获点（FACF）的弧距离关系进行判断，从而确定最大下降角度的方法，并进行仿真验证。结果表明：该方法可以在不同过渡航渡长度与不同最后进近下降角度的限制下，根据给定最高程序假设温度计算得到符合两种限制条件的最大下降角，为RNP 程序与ILS 程序衔接过渡的下降剖面设计提供了一种基于理论基础且具有可行性的设计方法。

A Maximum Descent Angle Design Method for RF segment to ILS Precision Approach

The combination of the RF segment of the RNP procedure and the traditional ILS precision approach procedure can make full use of the advantages of the two types of procedures, but the transition phase of the two procedures needs to consider the design of the maximum descent angle. This paper analyzes the plane and section geometric design parameter limitations of the transition phase procedure, and analyzes the operating limitations of the transition from satellite-based navigation to ground-based radio navigation that require stable interception of heading signals and glide slope signals. Combining two types of limitations, this paper designs a method that can calculate the relationship between the deviation of the glide path and the arc distance to the final approach course fix point (FACF) from different final approach point (FAP) heights to determine the maximum descent angle. Through simulation verification, it is proved that the proposed method can calculate the maximum descent angle that meets the two types of limitations under the different transitional flight lengths and different final approach descent angles, and according to the given maximum program hypothetical temperature. This method provides a theoretical basis and feasible design method for the descending profile design of the transition between the RNP procedure and the ILS procedure, and can provide a reference for the actual design of this type of procedure.