On 28 July 2011, Asiana Airlines Flight 991, a Boeing 747-400F cargo aircraft on a flight from Seoul, South Korea, to Shanghai, China, crashed into the sea off Jeju Island after suffering a main-deck fire. Both pilots, the only two people on board, were killed. The accident marked the second loss of a 747 freighter due to cargo hold fire in less than a year, following the crash of UPS Airlines Flight 6 in Dubai in September 2010. Accident Asiana Cargo Flight 991 was crewed by two pilots. Captain Choi Sang-gi (52) had logged 14,100 flight hours including 6,800 on Boeing 747 and 5,600 as Pilot In Command. First Officer Lee Jeong-woong (43) had logged 5,200 hours including 492 on Boeing 747. With a combined experience of over 19,000 flight hours, they took off from Seoul's Incheon International Airport at 03:04 on 28 July local time bound for Shanghai Pudong International Airport. The aircraft was loaded with 58 tonnes of cargo; most of the freight was standard cargo, semiconductors, mobile phones, liquid crystal displays, and light-emitting diodes. The remainder consisted of of lithium batteries and other potentially dangerous materials, such as paint and photoresist fluid. While cruising at less than an hour into the flight, at 03:54, the crew contacted air traffic control (ATC) reporting a fire on board, requesting an immediate descent and diversion to Jeju Airport, South Korea, for an emergency landing. The aircraft was observed on radar at 04:01, descending towards and then erratically climbing and descending for the following nine minutes, reaching an altitude of almost . In the last communications to ATC, the crew reported heavy vibrations and loss of flight controls authority. After a steep descent to , radio contact was lost at 04:11, when the aircraft was west of Jeju Island. Aircraft The aircraft involved in the accident was a four-engined Boeing 747-48EF with South Korean registration HL7604, the 1370th Built 747. Made its first flight on February 15, 2006 and delivered a week later to Asiana in February 22, 2006. The aircraft, a freighter version of the popular Boeing 747 passenger jet, had flown more than 26,300 flight hours, and its maintenance history did not reveal anything significant in relation to the accident flight. Search Search-and-rescue operations conducted by the Republic of Korea Coast Guard recovered parts of the aircraft within a day of the crash. The search effort involved a total