Is not the language of the airways English/US/Aus, ?
Peter R-B
What a silly question!
Theoretically so, maybe...but...
1. Pretty naiive to think a Chinese controller at a local Chinese airfield would speak to a local Chinese pilot in a local Chinese aircracft, in English!
(Before you say anything, just tune your airband radio to a local French airfield, or any local airfield anywhere in the world where English is not the native tongue....I'm sure you'll find them working in their own language rather than English.)
2. In fact it is common practice for the controllers to speak chinese to chinese pilots, and English (of a sort) to English pilots on the same frequency!
3. For those who believe that is a breach of international convention, consider the likelihood and risk of miscommunication if a Chinese controller at a local Chinese airfield would speak to a Chinese pilot in a Chinese aircracft, in English...their second language! Vs their own language. It would be utter meyhem based on much of the 'aviation English' coming out of that country I've heard!
At least let them understand each other when they can. While in the airspace where they mix the two, it's a little annoying if you're not a Chinese speaker...you miss much of the traffic, but I'd prefer that then hear them both struggle on in their Chinglish and end up smashing into me or a hill.
When in Rome....the Romans will do as they wish.
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Anyway, despite that presumably not being the topic at all or the reason for OP's thread question....(it 'presumably' being about the language of the training)
4. Wouldn't instruction be more effective in the student's mother tongue? (Irrespective of what they will eventually use once trained and on the job.)