Pilots are required to demonstrate that they possess the necessary active and passive skills in the languages used in aviation radio telephony. The requirements depend on the type of licence and the intended use of licences (VFR, IFR, etc.).
In order to be authorised to communicate on the radio during flight it is mandatory to hold a qualification for aeronautical radiotelephony. This qualification is issued after having passed an examination consisting of two parts: a written part which is examined in the framework of the official theoretical examinations for the acquisition of the licence respectively the instrument rating, and a practical part (simulated flight). In this exam, the candidate must demonstrate mastery of the ICAO standard phraseology and knowledge of the relevant regulations and procedures.
The practical VFR radiotelephony examination is deemed to be part of the theory exam and shall therefore be taken within the time limits applicable to pass the entire theory exam. The practical radiotelephony examination can be taken outside the 18-month period of the theory examination, but must be passed before the practical IR flight examination.
The practical radiotelephony examination for visual flight rules may be taken in English, German, French or Italian. To acquire an airline pilot licence or an instrument rating, the practical radiotelephony examination must be passed in English.
From 1st of January 2019, Art. 10a of the Air Navigation Act (LFG; SR 748.0) is applicable. The practical radiotelephony examination can still be taken in English, German, French or Italian according to visual flight rules. However, flights to, from and through a Swiss CTR, TMA, RMZ and FIZ are only permitted in English - subject to exceptions. In the other class E and G airspaces it is still possible to use the (currently published) local language for radio telephony with the flight information service in addition to the English language. This also applies to inactive CTR and TMA or aerodromes outside operating hours (HX). According to the new regulation, pilots in airspaces with "English only" must have an RTF entry in English with valid "Language Proficiency Level 4" in English. For pilots of balloons and gliders as well as for on-board technicians it is recommended to provide proof of "Language Proficiency". A "Language Proficiency" is neither necessary for them in Switzerland nor in cross-border traffic.
Theoretical and practical training in radiotelephony must be taken at an approved flight school. The content of the training and the examination is based on the respective programme according to EASA: Subject 90 (VFR) for the acquisition of a private pilot licence, a sailplane or a balloon pilot licence; subject 091 (VFR) for commercial and airline pilots; 092 (IFR) for the acquisition of the instrument rating.
Unrestricted radiotelephony licences or certificates acquired abroad will be recognised for endorsement of radiotelephony privileges in a Swiss licence, provided that the applicant holds a pilot license issued by the same country or a confirmation from the issuing authority. However, authorisations which are restricted at national level, e.g. limited to airspaces G and E, cannot be recognised.