The telephone call is a screening call and it shouldn't go for too long. Maybe 10 min or so, hard to say.
You'll be asked some technical questions however, you won't be expected to give text book perfect answers as you're "cold". However, I'd revise basic performance questions, such as "what's V1?" and other such questions.
Research the company, understand what Netjets does etc.
Your English standard will be assessed as well. If you're not fluent or comfortable with the English language, start brushing up on it.
If the call is inconvenient, such as picking up the kids, at the threshold etc you are quite within your rights to ask for another time.
You should hear fairly soon if you've been offered an interview.