use in 24hrs

hey all, it seems im asking all me questions at once but heres another that ive been looking at. Would it be fare to say that an aircraft ie a330 would spend around 15hours in the air out of 24 to make it most effective.
The reason i ask is ive been looking at emirates a330-243's coming into birmingham and the norm seems to be within a week we would see 3 different reged aircraft.
I was thinking could it be possible for 1 aircraft to make a daily 15 hour rtn flight or would there need to be more of a gap thats working on 15 hours in the air and 9 on the ground for 7 days straight. I know it can be done but my question is is it the norm??
The reason i ask is ive been looking at emirates a330-243's coming into birmingham and the norm seems to be within a week we would see 3 different reged aircraft.
I was thinking could it be possible for 1 aircraft to make a daily 15 hour rtn flight or would there need to be more of a gap thats working on 15 hours in the air and 9 on the ground for 7 days straight. I know it can be done but my question is is it the norm??