Between March 11 and 15 the navigation systems operated by Skyguide at Zurich Airport will be checked by means of measurement flights. Specifically, this involves the instrument landing systems (ILS and GBAS) of the various runways and the Kloten rotating radio beacon (VOR KLO). The measurement flights take place partly in the afternoon and at night, after the end of regular flight operations, until two o'clock in the morning at the latest. 

The periodic checks ensure the accuracy of the navigation equipment. For this purpose, approaches are required that start laterally, above and below the published flight path. For this reason, the survey flights sometimes take place off the usual flight paths. During a survey, the respective flight path is approached several times. In the process, the signals sent by the corresponding navigation equipment are recorded and evaluated.

The measurement flights will be carried out with a twin-engine propeller aircraft of the type Beechcraft King Air 350. The aircraft is equipped with state-of-the-art navigational aids and a high-precision flight inspection device. Skyguide air traffic control is responsible for the planning and execution of the flights.