Positioning accuracy and avairability of GBAS at the approach phase

摘要

This paper presents the results of flight experiments of our experimental GBAS (Ground Based Augmentation System). We executed approach and touch-and-go flights from 1,500 feet altitude for checking the performance of our experimental GBAS at the final approach region in Sendai airport. The tests were carried out with the experimental aircraft (Beechcraft B99 Airliner) loading a GBAS VDB receiver, GPS receivers (NovAtel MiLLen. STD. and Ashtech ZXtreme) and a PC for a GBAS airborne station. In 2002 experiments, the results of vertical errors (95) of GBAS positioning (with MiLLen. STD.) were about 0.49 m to 0.85 m at the region from 0 to 1 NM from runway threshold. Comparing to CAT-II and CAT-III specification of RTCA/DO-245, the results were satisfied with these values.