Air China was a Northwest Airlines partner but that agreement just ended this past summer. Here's the details from www.nwa.com
Air China operated flights between San Francisco/Los Angeles and Beijing/Shanghai, and codeshare connections from Beijing to Chengdu, Ghangzhou, Qinghao, Shenyang, Xiamen, and Xi'an.
500 miles minimum or actual mileage flown.
50% mileage bonus for purchased Business Class or First Class travel.
Air China serves more than 68 cities in China, as well as destinations throughout Asia, Australia, the Middle East and Europe.
*As of June 30, 2003, Air China will no longer be a WorldPerks partner. WorldPerks members may accrue miles on applicable Air China flights through June 30, 2003. Award redemptions on applicable Air China flights must be booked and ticketed by June 30, 2003 for travel to be completed by June 30, 2004. Lounge reciprocity will also be discontinued on June 30, 2003."
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