Study on Glide Slope’s Clearance Flight Check Criteria
Shuming Liu, Tong Liu, Huawei Ma, Flight Inspection Center of CAAC, China
Location: Regency Ballroom
Date/Time: Friday, Apr. 20, 9:00 a.m.
Flight check of Glide Slope (GP) clearance is a very important profile of ILS flight inspection. Compared with the GP angle/TCH or structure, sometimes the clearance check maybe not so noticeable, but at least 3 GPs did not pass the commissioning/periodic check in China during the past 2 years and it has aroused widespread concern in CAAC.
This paper introduces how Flight Inspection Center of CAAC (CFIC) conducts GP clearance check. As for the definition “The DDM below the ILS glide path shall increase smoothly for decreasing angle until a value of 0.22 DDM is reached” in ICAO Annex 10, the writers try to offer a suggestion on the threshold for the roughness/scalloping of clearance DDM curve considering the aircraft turbulence and the uncertainty of calibration instruments and others. Besides, the writers introduce some methods to improve the GP clearance through several typical cases.