Question: What is the world's largest low-cost U.S. airline carrier located as Bishop International Airport?
Context: Bishop International Airport (IATA: FNT, ICAO: KFNT, FAA LID: FNT) is a commercial and general aviation airport located in Flint, Michigan.  It is named after banker and General Motors board member Arthur Giles Bishop (April 12, 1851 – January 22, 1944), who donated 220 acres of his farmland for the airport in 1928.  The third busiest airport in Michigan, it surpassed competitor MBS International Airport in terms of airline operations in 2002.  In 2007, 1,071,238 passengers used Bishop International Airport; in 2011, 938,914 passengers used the airport.  It is included in the Federal Aviation Administration (FAA) National Plan of Integrated Airport Systems for 2017–2021, in which it is categorized as a small hub primary commercial service facility.  The airport is currently served by several passenger airlines: Allegiant Air, Southwest Airlines and Delta Air Lines operate mainline service out of the airport, as well as affiliates of Delta Connection, United Express and American Eagle.  Additionally, FedEx Express and a FedEx Feeder affiliate operate cargo services out of the airport.  Accompanying the airlines is fixed-base operator Av Flight that handles both general aviation and airline operations and the flight school American Wings Aviation.  Bishop International Airport is in southwestern Flint, and is surrounded by Flint Township to the north, east and west; and Mundy Township to the south. Air Wisconsin Airlines is a regional airline based at Appleton International Airport in the town of Greenville, Wisconsin, United States, near Appleton.  Air Wisconsin is the largest privately held regional airline in the United States.  It currently operates regional jet flights as American Eagle under contract to American Airlines via a code sharing agreement, serving cities in the U.S. and Canada with hubs at Boston Logan International Airport (BOS), Charlotte Douglas International Airport (CLT), Philadelphia International Airport (PHL) and Ronald Reagan Washington National Airport (DCA) .  Air Wisconsin previously operated United Express service on behalf of United Airlines followed by US Airways Express service on behalf of US Airways prior to becoming an American Eagle regional air carrier.  The company has announced it will once again partner with United Airlines as a United Express code sharing air carrier with primary hubs to be located at Chicago O'Hare International Airport (ORD) and Washington Dulles International Airport (IAD) beginning in September 2017 and will be "exclusively operating" as United Express by March 2018. A low-cost carrier or low-cost airline (also known as "no-frills", "discount" or "budget" carrier or airline, or "LCC") is an airline that generally has lower fares and fewer comforts.  To make up for revenue lost in decreased ticket prices, the airline may charge for extras such as food, priority boarding, seat allocating, and baggage.  As of July 2014, the world's largest low-cost carrier is Southwest Airlines, which operates in the United States and some surrounding areas. Southwest Airlines Co. () is a major U.S. airline and the world's largest low-cost carrier headquartered in Dallas, Texas. Olympic Air S.A. (Greek: Ολυμπιακή ) is a regional airline, a subsidiary of the Greek airline carrier Aegean Airlines.  It was initially formed from the privatization of the former Greek national carrier Olympic Airlines, a company that carried the name Olympic Airways from 1957 to the beginning of the 21st century.  Olympic Air commenced limited operations on 29 September 2009, after Olympic Airlines ceased all operations, with the official full-scale opening of the company taking place two days later on 1 October 2009.  Its main hub is Athens International Airport, with Rhodes International Airport serving as secondary hub.  The airline's headquarters are in Building 57 at Athens International Airport in Spata, and its registered seat is in Koropi, Kropia, East Attica. Norwegian Air Shuttle ASA (), trading as Norwegian, is a Norwegian low-cost airline.  It is the third largest low-cost carrier in Europe, the largest airline in Scandinavia, and the ninth-largest airline in Europe in terms of passenger numbers.  It offers a high-frequency domestic flight schedule within Scandinavia and Finland, and to business destinations such as London, as well as to holiday destinations in the Mediterranean and the Canary Islands, transporting over 30 million people in 2016.  The airline is known for its distinctive livery of white with a red nose, with portraits of distinguished Scandinavians on the tail fins of its aircraft. America West Airlines was a U.S. airline headquartered in Tempe, Arizona.  Their main hub was at Sky Harbor Airport in Phoenix, Arizona, with a secondary hub at Las Vegas McCarran International Airport in Las Vegas, Nevada.  The airline became part of the US Airways Group after it acquired the larger airline in 2005 and adopted the US Airways brand name.  America West was the second largest low-cost carrier in the U.S. after Southwest Airlines and served approximately 100 destinations in the US, Canada, and Mexico.  Service to Europe was provided through codeshare partners.  In March 2005, the airline operated a fleet of 132 aircraft, with a single maintenance base at Sky Harbor Airport in Phoenix.  Regional jet and/or turboprop feeder flights were operated on a code sharing basis by Mesa Airlines and Chautauqua Airlines as America West Express. AirAsia Berhad () is a Malaysian low-cost airline headquartered near Kuala Lumpur, Malaysia.  It is the largest airline in Malaysia by fleet size and destinations.  AirAsia Group operates scheduled domestic and international flights to more than 165 destinations spanning 25 countries.  Its main hub is klia2, the low-cost carrier terminal at Kuala Lumpur International Airport (KLIA) in Sepang, Selangor, Malaysia.  Its affiliate airlines Thai AirAsia, Indonesia AirAsia, Philippines AirAsia, and AirAsia India have hubs in Don Mueang International Airport, Soekarno–Hatta International Airport, Ninoy Aquino International Airport, and Kempegowda International Airport respectively, while its sister airline, AirAsia X, focuses on long-haul routes.  AirAsia's registered office is in Petaling Jaya, Selangor while its head office is at Kuala Lumpur International Airport. Maurice Bishop International Airport (IATA: GND, ICAO: TGPY) , formerly known as Point Salines International Airport, is an international airport located in the parish of St. George's.  The town of St. George's is about 5 mi north of the airport and is the capital of the island nation of Grenada.  The airport is located on Point Salines, the most southwestern point of the island. Johan Adolf Pengel International Airport (IATA: PBM, ICAO: SMJP) , also known as Paramaribo-Zanderij International Airport, and locally referred to simply as JAP, is an airport located in the town of Zanderij and hub for airline carrier Surinam Airways, 45 km south of Paramaribo.  It is the larger of Suriname's two international airports, the other being Zorg en Hoop with scheduled flights to Guyana, and is operated by Airport Management, Ltd./ NV Luchthavenbeheer.
Answer: Southwest Airlines