Southwest Airlines expanding in Phoenix

PHOENIX -- Southwest Airlines plans to boost its already strong presence in Phoenix with a major expansion at Sky Harbor International Airport in the next five years.

No, the carrier isn't building a jazzy international concourse like it has in Houston and is opening in Fort Lauderdale. Nor will it add glamorous new destinations in Mexico, the Caribbean and Central America.

But new Phoenix flights are definitely on the agenda: Southwest is adding eight gates to the 24 it already occupies in Terminal 4. The airline, the No. 2 carrier at Sky Harbor behind American with more than 170 daily non-stop flights to 50 cities, averages 10 flights per day from each gate.

The Dallas carrier has committed to be the tenant of a new eight-gate concourse due to open in 2021, Southwest President Tom Nealon said Wednesday. The gates will be near Southwest's D gates, which debuted in 2005.

"Southwest Airlines is fully on board,'' Nealon said at a luncheon of the PHX Aero Club. "We want that concourse.''

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In addition to the new gates, Southwest plans to double the size of its maintenance center at the airport, going from two bays to four.

"You don’t increase your maintenance capacity and your maintenance facility unless you intend to fly your planes (here) full of passengers,'' he said. "We're not going to fly any planes (to Phoenix solely for) maintenance.''

The tab for maintenance expansion plus the replacement of its provisioning center and ground-service equipment facility: $40 million.

Nealon said the gates are necessary in part to accommodate Southwest's larger Boeing 737s. Seven of its 24 current gates cannot accommodate them, he said. The airline has not said whether it will use 32 gates at Sky Harbor when the new concourse is completed. Nealon said it's possible a few gates could be given up in Southwest's other concourses but that the bottom line is the airline is adding capacity in Phoenix.

The gates will be known informally as the "high D" gates, to differentiate them from the existing D gates. There is a similar set-up in the A, B and C concourses, each of which has two wings. Southwest also has gates in the C concourses.

The Phoenix City Council approved the new concourse, a $250 million investment, last fall but tenants were not identified. Southwest and American, the city-owned airport's dominant carriers and Terminal 4 tenants, declined to comment at the time. It is the eighth and final concourse planned for Terminal 4, which opened in 1990.

Terminal 4 accounts for more than 80% of Sky Harbor's passenger traffic.

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Southwest was the most likely candidate because American has been shrinking at Sky Harbor in the past year due to flight cuts and a shift to smaller planes on some routes. The airline has been fine-tuning supply and demand at the hubs of the combined American and US Airways, which merged in 2013. US Airways was based in Tempe, Ariz., and had more flights and planes than it needed at Sky Harbor. The new American remains the largest carrier at Sky Harbor and has thousands of employees here.

Nealon said the leasing of the new gates and the $40 million investment are signs that Southwest is here to stay. Phoenix is the airline's sixth busiest city in terms of daily departures. Sky Harbor and Las Vegas used to trade places for the No. 1 spot years ago but Chicago, Baltimore and Denver now top the list because of rapid expansion there in the past several years.

"Our desire and our objective is to be the hometown carrier that Phoenix can count on year after year after year,'' Nealon said.

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