Pulling your hair with "simplified English" in matters of maintenance...?
Believe me - same problem with many airlines - for flight crews.
I have to deal with this in Argentina.
My aviation education and pilot background is 100% in English.
All our procedures, manuals, check lists are English.
In the cockpit, we speak "Spanglish" performing check-lists...
But, yes, it is not easy for some.
Some years ago, having a temporary contract, I had a Belgian F/O and a Swiss F/E...
They realized I could speak French, like they did, as well as a native.
So in the cockpit, they suggested we spoke French for check-lists.
What a disaster. My French vocabulary for aviation is nowhere. I was lost.
In South America, I frequently use Spanish for ATC communications.
But as far as Spanish in cockpit procedures, or maintenance write-ups, sorry, only in English, please.
Our books are published by Boeing, in English. Therefore, we use English.
English is the IDEAL technical language in aviation. A sentence of 3 or 4 lines in Spanish or French, can be clearly translated with 2 lines of English.
Honest, I adore Spanish and French as social and every-day languages, but technical - NO...