美国联邦航空管理局周五下午采取了非同寻常的举措，发布全国范围的停飞令。所有机场均无飞机起飞，数百万乘客滞留。
What we know about the FAA nationwide ground stopThe Federal Aviation Administration took an extraordinary step Friday afternoon by issuing a nationwide ground stop. No planes are taking off at any airport and millions of passengers are stranded.