A modeling approach to teardrop pattern for general aircraft PBN operation

The teardrop pattern is one of the key subjects in IFR flight training. To quantitative evaluate the teardrop pattern quality for general aircraft performance-based navigation (PBN) operation, an approach for the nominal trajectory of the teardrop pattern modeling is proposed. Firstly, the nominal track of the teardrop pattern is modeled in the airport plane coordinate system, and then the key waypoint latitude and longitude coordinate conversion equations of the teardrop pattern model are derived based on the geocentric geodetic coordinate system. Based on the waypoints coordinate conversion modeling, the fast waypoint coordinates determining method for teardrop pattern are given using the flight parameter data. The proposed method will provide valuable information for the flight technical error (FTE) and the navigation performance calculation, which are the premises for quantitative training evaluation with PBN general aircraft.