Design and Testing of a Vertically Guided High Precision Approach into Salzburg Airport

Abstract

The approach to landing on runway 33 of Salzburg Airport, Austria is severely impacted by mountainous terrain on the extended runway centerline. This renders all straight-in approaches but those based on Required Navigation Performance (RNP) Authorization Required (AR) impossible. Only the high navigation accuracy available under RNP AR minimizes the required obstacle protection areas sufficiently to be not penetrated by terrain. The combination of RNP AR and Localizer Performance with Vertical guidance (LPV) makes it furthermore possible to use a more precise angular guidance for the final approach. In Salzburg, this enables a reduction of the decision height from 368 ft to 218 ft above aerodrome level as critical terrain and obstacles now fall outside of the protection areas. A Level D full flight simulator test with an Airbus A350 showed that advanced RNP 0.1 coding is sufficient to achieve RNP 0.1 performance under all permitted environmental conditions.