Using UAV Multicopters as an Extension of ILS Ground Measurements: This Innovative Idea has Already Become Reality in Switzerland!
Hervé Demule, Skyguide, Swiss Air Navigation Services, Switzerland; Klaus Theissen, Rohde & Schwarz
Location: Regency Ballroom
Date/Time: Thursday, Apr. 19, 10:40 a.m.
End 2015, Geneva, the first successful trials with an UAV multicopter carrying an ILS receiver concluded the first stage of the feasibility study. Indeed, these very promising first ILS measurements provided skyguide engineers many positive answers to their initial questions. Yes, it is possible and very worthfull to measure ILS signal in the farfield region with a multicopter. Yes, the stability and accuracy of the flight with a heavy and expensive payload were very acceptable. Yes, the accuracy and repeatability of the measurements fulfilled the expectations, and even much more. Yes, a very good level of correlation with flight checks had already been achieved.
Skyguide, the swiss air navigation service provider, who had already developed a mobile bench for ILS ground measurements with a vehicle, has always put a lot of importance in ILS ground measurements techniques, in order to achieve the best possible repeatability and correlation with flight checks, as recommended by ICAO Document 8071.
For Localizer, skyguide had already successfully applied the "double" correlation technique between monitor data, ground and flight checks results. Indeed, for many years, the ground vehicle equipped with the skyguide software ILS Checker interfaced to the ILS receiver R&S®EVS300 from Rohde&Schwarz and RTK GPS enabled to set high standards in terms of LOC ground measurements.
However, for Glide Path, the old fashioned method with a telescopic mast positioned at the threshold, thus in the nearfield region, has never reached an acceptable level of correlation with flight checks. Indeed, too close to the Glide Path, these measurements can only have a relative value, but no absolute value: If a change is detected in the nearfield, what will be the impact in the farfield? This question is nearly impossible to answer with such a technique.
The solution consists in measuring the Glide Path at a distance of at least 1 km, thus it is required to lift the receiver to a minimum height of approximately 50 m, better 80 m if possible. Thus UAV multicopter based measurements are the only way to meet this requirement and become simply necessary.
From the initial idea and concept to the implementation of a mature solution, this paper describes the development project, the multicopter based measurement system and its achievements in terms of repeatability and accuracy. Skyguide is now using an UAV multicopter with an R&S®EVSF1000 from Rohde&Schwarz for preventive and corrective ILS maintenance. It opens new horizons in term of ILS measurement techniques: for new ILS commissioning and replacement, it enables a very good preparation of the equipment before commissioning flight checks.