Delta Air Lines plans to grow in the competitive Northwest marketplace by significantly increasing its presence at Seattle-Tacoma Airport, and the airport is expected to reciprocate with expanded and improved facilities in anticipation for the increased number of flights.

Delta, and its Delta Connection partners, already rank second-busiest at Seattle, after Alaska Airlines and its Horizon partner. But the Atlanta-based carrier has set its eyes on developing a hub with wide-reaching links. In particular, Delta is establishing new nonstop flights to Asia from Sea-Tac, with new links to Hong Kong and Seoul having commenced in June, alongside its European network.

Many commentators have jumped to the conclusion that this move is all part of a greater plan for Delta to wipe out Alaska's dominance in preparation for a takeover. Delta Air Lines Chief Executive Richard Anderson insists the move is "just business."

It should not be too much of a surprise that Seattle has been chosen for a hub. Delta merged with Northwest Airlines in 2010, and prior to that Northwest had always maintained a strong presence in the city. Many of the routes and operations inherited in the merger were focused on Seattle, not to mention loyal passengers.

Whatever the truth is surrounding famously-neutral Alaska Airlines, in the short term the new hub is likely to bring about a fare war between the two carriers, and more choice (some say overcapacity) for passengers in the region. Both Alaska and Delta operate in competition on a number of key routes from the airport, particularly to cities in Alaska, where service on some routes is flown on an hourly basis.

Overall, Delta plans to triple the number of daily departures from Seattle by the end of the year. It will also plant many of its hundreds of newly-recruited pilots and flight attendants into the hub operation to cater to the "more flight options, more routes and connections, more perks and special offers, and cheaper airfares" expected.

Aside from the issue of Alaska Airlines, Delta is also contending with the much larger hub airport of Vancouver, only a short distance from Seattle. The airline's vice president of network planning, Bob Cortelyou told Aviation Pros that his airline's flexible fleet should be able to match Seattle's proximity to Asia in developing strong trans-Pacific routes.

Seattle-Tacoma operator Port of Seattle also believes in its potential.

"The continued growth of international connections through Sea-Tac are a major factor in the region's record tourism growth, which promotes trade, business development and generates good jobs throughout the Pacific Northwest," Mark Reis, managing director of Sea-Tac Airport, said at the launch of Delta's Seoul route.

Coinciding with Delta's announcement, Port of Seattle is planning a new $350 million international arrivals facility that will cater to Delta's (and Alaska's) planned growth, but will be paid for through airline users. The new facility will be fully operational by 2018, by which time Delta will be fully established and, it hopes, offering more international services.

Whether overcapacity has become an issue by this time remains to be seen. And whether any mergers will have occurred is anyone's guess.