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Delta/Alaska Friendship Frays as Airlines Bulk Up in West Coast Hubs

Tickers in this article: AAMRQ ALK DAL UAL

SEATTLE (TheStreet) -- Alaska Air and Delta are partners, but increasingly they are also rivals battling for control of Seattle Tacoma International Airport, one of the two most valuable West Coast hubs.

The bloodiest battleground appears likely to be the Seattle-San Francisco route, where service is slated to expand next year to approximately 28 daily flights each way.

As the growth in Asia travel continues, as the Boeing 787 opens new trans-Pacific routes, and as American prepares to emerge from bankruptcy, the importance of having a West Coast hub only increases. Not to ignore legacy carrier purchases of West Coast airlines in the late 1980s, but that was a domestic battle while the focus now is on serving Asia.

United has San Francisco. American would like to have Los Angeles but dominance there is probably unattainable. Delta has staked out Seattle, where it wants a bigger domestic share. For the 12 months ended in June, Alaska had a 53% share of Seattle's domestic traffic, while Delta was second with about 10%.

Delta said this month it will add six daily Seattle-San Francisco flights starting in March, with a seventh flight to be added in June. It will add two daily Seattle-Las Vegas flights in January, with two more in April, bringing the total to five. It will add two daily Seattle-Los Angeles flights in June, bringing the total to seven. Regional partners will operate most of the new service.

Delta said its primary goal is to better feed its growing international hub in Seattle, but clearly its expansion goes beyond what it takes to feed international flights. From Seattle, Delta currently operates 38 peak-day departures to 16 destinations, including seven international destinations, while Alaska offers about 300 daily departures. Delta's planned new routes target critically important routes for Alaska, which already has 12 daily Seattle-Los Angeles routes, eight daily Seattle-San Francisco routes and nine daily Seattle-Las Vegas routes.

By mid-2014, Delta expects to fly from Seattle to nine international destinations including Amsterdam, London and Paris and six in Asia: Beijing, Hong Kong, Osaka, Shanghai, Seoul and Tokyo. "We'll continue to grow the market into a preferred international gateway," said Delta spokesman Anthony Black.