By Diplomacy Journal Lee Kap-soo

Korean Air Flight KE189, which departed Incheon International Airport for Taichung International Airport in Taiwan, was diverted due to an airframe defect.

Flight KE189 took off at 4:45 p.m., and about 50 minutes later, while flying over Jeju Island, a message was displayed stating that there was an "abnormality in the pressurization system". 

The pressurization system regulates the pressure inside the aircraft. The Boeing 737 MAX 8 in question is a Boeing 737 MAX 8, which was identified last October as having a 'pressure bulkhead' abnormality, leading to a global investigation into the defect. 

The pressure bulkhead is a partition wall between the cabin and the tail wing that allows the interior of the airplane to withstand high pressure from the outside.

The plane returned to Incheon Airport around 7:40 p.m. as Korean Air decided to turn around. According to the Ministry of Land, Infrastructure, Transport and Tourism, more than 10 passengers complained of ear drum pain and hyperventilation during the altitude reduction before the turnaround, and 13 of them were taken to the hospital after landing. No one was reportedly seriously injured.

Korean Air substituted another aircraft for Flight KE189, which departed again at 10:30 a.m. on June 23, 19 hours later. "We sincerely apologize for the inconvenience caused to the passengers on the flight and will minimize their inconvenience by providing accommodation," a Korean Air official said, adding, "We are investigating the exact circumstances of the turnaround and will begin maintenance after inspecting the aircraft."