Questions about phraseology
I just read Doc.4444 Phraseology again, I found that controller should say"descend to XX ft" , but so many controllers use "descend and maintain" or "descend to and maintain", can somebody tell me why or what are the differences?
One more question is about the rules to read an aircraft registered number, according to the rule we have in China, if all the registered number is in words, such as ACGDS, I can read ADS for short, but what if some numbers in it? Such as ACGD1, A565T? Is there any rule for that?