Claim: As of December 2020, the longest-serving aircraft of Korean Air (the largest airline and flag carrier of South Korea based on fleet size, international destinations and international flights) is the Boeing 777-300ER.
Evidence: Korean Air Co., Ltd. (Korean: 주식회사 대한항공; Hanja: 株式會社 大韓航空; RR: Jusikhoesa Daehan Hanggong), operating as Korean Air, is the largest airline and flag carrier of South Korea based on fleet size, international destinations and international flights. As of December 2020, the Korean Air fleet consists of the following aircraft: Korean Air Fleet Airbus A220-300 10 Airbus A330-200 8 Airbus A330-300 21 Airbus A380-800 10 Boeing 737-800 5 Boeing 737-900 6 15 Boeing 737-900ER Boeing 747-400 1 Boeing 747-8I 10 Boeing 777-200ER 12 Boeing 777-300 4 Boeing 777-300ER 26 Boeing 787-9 10 Boeing 747-400ERF 4 Boeing 747-8F 7 Boeing 777F 12 AgustaWestland AW139 4 Boeing 737-700/BBJ1 1 Bombardier Global Express XRS 1 Gulfstream G650ER 1 Sikorsky S-76+ 1