Radiotelephony (RTF) provides the means by which pilots and air traffic services personnel communicate with each other. Used properly, the information and instructions transmitted are of vital importance in assisting in the safe and expeditious operation of aircraft. However, the use of non-standard procedures and phraseology can cause misunderstanding. Incidents and accidents have occurred in which a contributing factor has been the misunderstanding caused by the use of
non-standard phraseology. The importance of using correct and precise standard phraseology cannot be over-emphasised.

The following phraseology has been established for the purpose of ensuring uniformity in RTF communications. Obviously, it is not practicable to detail phraseology examples suitable for every situation which may occur. However, if standard phrases are adhered to when composing a message, any possible ambiguity will be reduced to a minimum. Concise and unambiguous phraseology used at the correct time is vital to the safe and expeditious operation of air traffic.

First of all a good transmission technique is needed!