If Los Angeles International Airport already feels like a confusing mess to navigate, you may want to stay clear in mid-May.
That is when Delta Air Lines will move its operations to Terminals 2 and 3 from Terminals 5 and 6, forcing 19 other carriers to relocate during what is expected to be a hectic five-day period.
Delta officials are describing the move, which starts May 12 and is expected to wrap up May 17, as the biggest relocation operation in airport history. They say they are trying to minimize disruptions by getting the word out to travelers and transportation companies, beefing up staffing to direct lost passengers and conducting extensive planning for the massive logistical operation.
"It is a big thing," said Ranjan Goswami, vice president of sales for Delta's western division. "It is unprecedented."
Business travelers who routinely fly out of LAX say they hope they can avoid the airport during the move.
"The bottom line is that it's going to add to everyone's stress," said Jason Womack, a leadership speaker from Ojai who flies out of LAX about twice a month. "LAX police are going to be inundated with questions."
The move is meant to give Delta Air Lines room to grow, adding seven extra gates and giving the carrier easier access to the airport's international terminal and to Delta's partners, including Aeromexico, Virgin Atlantic and WestJet.
The Atlanta-based carrier is investing $1.9 billion over the next four years to upgrade its two new terminals.
Delta's move is just the latest in a series of terminal shuffles and renovation projects by several carriers at LAX, which has been expanding and upgrading to take advantage of the increasing demand for travel in and out of Los Angeles.
Although Hartsfield–Jackson Atlanta International Airport is the nation's busiest airport, more passengers begin and end their air trips at LAX than at any other airport in the United States.
Nearly 81 million passengers flew in and out of LAX in 2016, a 31% increase over 2011, according to airport statistics.
But more than sheer numbers are prompting airlines to invest in LAX. The airport also serves the lucrative L.A.-to-New York route that is favored by film, entertainment and business executives.
In addition, LAX is a burgeoning entry port for international visitors from Asia and Latin America.
"There is no surprise that the airlines are investing billions of dollars at LAX, helping to modernize all the terminals," said Deborah Flint, chief executive of Los Angeles World Airports, which runs LAX. "No one carrier dominates this airport, which presents an attractive place and competitive market for the airlines to invest."
Airlines have swapped terminals before, but not on the scale of what's planned for May.
In 2014, American Airlines, the busiest carrier at LAX, moved its operations out of Terminals 3 and 4 and into Terminals 4 and 6, to add extra gates and terminal space. The move also allowed passengers to connect by an underground tunnel, eliminating the need for travelers to leave the building to make a connection.
Subsequently, American moved out of Terminal 6 and currently operates out of Terminals 4 and 5.
Also in 2014, Southwest Airlines launched a $508-million renovation program at Terminal 1, creating a more spacious ticketing lobby, an automated baggage-check system, along with a new facade and seismic-retrofitting work.
Most of those investments were deducted from the lease fees the airlines pay the airport.
Delta's upgrade project will begin next year, starting with overhauling the structure between Terminals 2 and 3 to hold a new check-in facility, a screening area and a VIP lounge called the Delta Sky Club. The lounge will include a "sky deck" — an outdoor patio with views of the runways. Eventually, Delta wants to tear down and rebuild Terminal 3 to meet modern seismic standards and to include a connection with the adjacent Tom Bradley International Terminal.
"Our goal here is to have the best terminal complex to have the best customer experience," Goswami said.
One of the problems with Delta's current location at LAX is that passengers connecting between a Delta flight and one of Delta's airline partners must sometimes leave their arrival gate, walk out to the airport sidewalk and reenter at a connecting gate, which requires them to go through a security screening again.
"We need to have the connectivity to be seamless," Goswami said.
The upcoming move to make way for Delta's expansion project could cause significant confusion for travelers.
For Delta to move into Terminals 2 and 3, the following airlines must move out: Aer Lingus, Air Canada, Avianca, Copa, Hainan Airlines, Hawaiian Air, Interjet, Qatar Airways, Sun Country, Thomas Cook, Volaris, XL Airways France, Allegiant Air, Boutique Air, Frontier, JetBlue, Southwest, Spirit, Virgin America and Virgin Australia.
Air Canada, Virgin America, XL Airways France and Boutique Air will head to Terminal 6 while Hawaiian, JetBlue, Spirit, Allegiant, Frontier and Sun Country will relocate to Terminal 5. The other carriers will fly out of the Bradley International Terminal. A map showing the changes can be found at www.LAXishappening.com.
Delta will pick up the $60-million tab for the airlines' relocation.
Aeromexico, Virgin Atlantic and WestJet, which are partnered with Delta, will remain in Terminals 2 and 3. On some days during the five-day move, Delta will operate out of four terminals, located on opposite sides of the airport.
Delta will try to keep the confusion to a minimum by employing extra workers to help direct passengers to the correct terminal and will add shuttle buses on the tarmac side of the terminals and on the public road to transfer passengers who arrive at the wrong gates.
The airline is also urging passengers to use Delta's online app and check www.laxishappening.com to get the latest updates on the move.
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4:20 p.m.: This story was updated to explain where various airlines will be after the move and to include comments from a regular air traveler and the chief executive from Los Angeles World Airports.