deregulation, United no longer served Atlanta, while Southern successor Republic was the airport's third-largest carrier. Eastern was a larger airline than Delta until deregulation in 1978, but Delta was early to adopt the hub-and-spoke route system, with Atlanta as a hub between the Midwest and Florida, giving it an advantage in the Atlanta market. Eastern ceased operations in 1991 because of labor issues; American Airlines considered establishing an Atlanta hub around that time but decided Delta was too strong there and instead replaced Eastern's other hub in Miami. TWA created a small hub at Atlanta in 1992 but abandoned the concept in 1994 leaving Delta with a monopoly hub at Atlanta. From the 1980s until Eastern's demise in 1991, Delta occupied ConcourseA and part of ConcourseB, Eastern occupied the remainder of ConcourseB and ConcourseC, other domestic airlines used ConcourseD, and ConcourseT was used by international flights. By the mid-1990s, Delta's hub grew to occupy all of ConcourseB and the southern half of ConcourseT, and international flights moved to the new ConcourseE. ValuJet was established in 1993 as low-cost competition for Delta at ATL. However, its safety practices were questioned early, and the airline was grounded after the 1996 crash of ValuJet Flight 592. It resumed operations in 1997 as AirTran Airways and was the second-largest airline at ATL until it was acquired by Southwest in 2011 and absorbed into Southwest on December 28, 2014. Southwest is now the airport's second-largest carrier. Facilities Terminals Hartsfield–Jackson Atlanta International Airport has two terminals and seven concourses with a total of 192 gates. The Domestic Terminal is located on the west side of the airport and the Maynard H. Jackson Jr. International Terminal is on the east side of the airport. The terminals and concourses are connected by the Transportation Mall, a pedestrian tunnel with a series of moving walkways and The Plane Train, an automated people mover. All international arrivals are processed in Concourses E and F; Concourse F is the only concourse in the airport that has a gate that can support an Airbus A380, the largest passenger aircraft in the world. All non-Delta international carriers operate their ATL flights from this terminal, including Delta’s Skyteam partners such as Aeromexico, Air France, KLM, Korean Air and Virgin Atlantic. Concourse T contains 21 gates. Concourse A contains 29 gates. Concourse B contains 32 gates. Concourse C contains 34 gates. Concourse D contains 40