While flying from Seoul, South Korea to Shanghai, China, Asiana Airlines Flight 991 develops an in-flight fire in the cargo hold. The Boeing 747-400F freighter attempts to divert to Jeju International Airport, but crashes into the sea South-West of Jeju island, killing both crew members on board.

Seoul, officially Seoul Special Metropolitan City, is the capital and largest city of South Korea. The broader Seoul Metropolitan Area, encompassing Seoul, Gyeonggi Province and Incheon, emerged as the world's sixth largest metropolitan economy in 2022, trailing behind New York, Tokyo, Los Angeles, Paris, and London, and hosts more than half of South Korea's population. Although Seoul's population peaked at over 10 million, it has gradually decreased since 2014, standing at about 9.6 million residents as of 2024. Seoul is the seat of the South Korean government.

Shanghai is a direct-administered municipality and the most populous urban area in China. The city is located on the Chinese shoreline on the southern estuary of the Yangtze River, with the Huangpu River flowing through it. The population of the city proper is the second largest in the world after Chongqing, with around 24.87 million inhabitants in 2023, while the urban area is the most populous in China, with 29.87 million residents. As of 2022, the Greater Shanghai metropolitan area was estimated to produce a gross metropolitan product (nominal) of nearly 13 trillion RMB. Shanghai is one of the world's major centers for finance, business and economics, research, science and technology, manufacturing, transportation, tourism, and culture. The Port of Shanghai is the world's busiest container port.

Asiana Airlines Flight 991 was a cargo flight operated by Asiana Airlines. On 28 July 2011, the Boeing 747-400F flying from Seoul, South Korea, to Shanghai, China, crashed into the sea about 81 miles west off of the coast of Jeju Island after suffering an in-flight cargo fire. Both pilots, the only two people on board, were killed. The accident marked the second loss of a 747 freighter due to a cargo hold fire in less than a year, following the crash of UPS Airlines Flight 6 in Dubai in September 2010.