Have you heard the expression: ‘English is the language of the air’?
Aviation safety has always been challenging, but more challenging in the past due to miscommunication. In the early days of air travel, inability to communicate in a general language resulted in air mishaps, resulting in a quest for a permanent solution.
In 1951, the International Civil Aviation Organisation recommended English as the language of aviation. In 2008, it decreed that proficiency in English is mandatory for all Air Traffic Controllers as well as Flight Crew Members who have one thing or the other to do with international flights.
By extension, every pilot must learn the language, regardless of their origin.