and international air transportation association. reporter: ukraine authorized flights above 32,000 feet, an altitude that was considered safe. nonetheless some airlines did avoid the area unless the air space is restricted it s their call whether to fly through. carriers like british airways and air france flew around the conflict zone altogether. so did qantas, asiana, and china airlines. carriers likeless airlines flew directly over the war zone. you can t simply take every air space that might have a problem and say we re not going to fly there because as i say, the global scope of that would be enormous. reporter: late this week the dangers of the air space now abundantly clear. the aviation authorities took action. the aviation arms of the u.n.