It means 'until the flight' here but 'uçuşa' literally means 'to flight'.
so how does "Uçuşa" mean "until the flight" what kind of structure is this ?
Correct me if İ'm wrong, but İ think of it like 'to,' as in location '-a.' Five hours 'to' the flight.
I agree, is there a mistake here?
I don't think it is a mistake but your suggestion is better so "Five hours to the flight." should the main answer I think and "(There are) five hours until the flight." alternatives.
"It is five hours to the flight" is accepted
There are five hours for the flight
Is it wrong?
That would suggest that 5 hours are allowed for the flight; i.e. the flight itself would be 5 hours long. That is not the same meaning.
Would kadar make this sentence easier.