The reasons such as aging, genetic degeneration, local dystrophy immune, metabolic abnormalities, trauma, poisoning, radiation, etc., can cause lens metabolic disorder which directly cause lens protein denaturation and produce cloudy. That is the cataract. You'd better take a rest of more than a week before you go to take a plane which may cause your eye pressure increase suddenly. Then it will be harmful for you eyes. At last, you'd better take two weeks' rest in case of the recur.
It had better take two weeks to fly after cataract surgery. However, most people could fly the day after cataract surgery if that was needed. Almost all ophthalmologists require their patients to be examined the first day after cataract surgery and again at about 5-8 days. Because the higher the altitude, the higher pressure the person would gain. Because of the people who have cataract surgery would have a wound on the eye, the high pressure would make it broke again and make the condition worse.