The process of periodic calibration of the different radio aids used in aviation, as well as the airspace involved in the different procedures based on radio aids, is called flight inspection (Flight Inspection in English).

With specially equipped aircraft, the Flight Inspection is responsible for validating and certifying the continuity, integrity, accuracy and precision of the radio parameters offered by the different radio aids to air navigation.

To do this, said parametry is compared with the reference standards offered by the regulations of international organizations: the ICAO (International Civil Aviation Organization) or the FAA (Federal Aviation Administration).

All planes use the information provided to them by a series of stations. This information can be of different types (angular, distance, approach...). VOR, ILS, MB, NDB, DME type radio aids, or PAPI or VASI type visual aids, require periodic verification that the signals they emit are still sufficiently precise, have not lost power, continue within tolerances or provide correct information, since any failure of this type could impact flight safety. In any case, the radio infrastructure of each nation's airspace must be certified so that the published information used by crews is truthful and useful, ensuring airway procedures and instrument approaches.