International Travel - between North America and Africa / Asia / Europe / India / Middle East)
Coach Class: Each ticketed passenger is allowed two (2) pieces of checked luggage.
Both pieces: 50 pounds (23 kg) with linear dimensions not to exceed 62 inches (158 cm) per piece.
* Exceptions for travel wholly between U.S./Canada and the Philippines, Hong Kong or China, checked pieces may weigh up to 70 pounds (32 kg) each.
网站上这么说的,不知F1算不算Exceptions http://www.nwa.com/travel/luggage/checked.html