KE189 - Pressurization System Failure Causes Emergency Descent

Korean Air flight 189 departed Seoul Incheon International Airport (ICN) at approximately 4:45 p.m. local time on 22 June 2024 en route to Taichung International Airport (RMQ) in Taiwan. The Boeing 737 MAX 8 (registration HL8352) was carrying 125 passengers and crew members. Approximately 50 minutes into the flight, while cruising at an altitude exceeding 30,000 feet, the aircraft's pressurization system suddenly malfunctioned. The cabin lost pressure, triggering the automatic deployment of oxygen masks throughout the aircraft. The flight crew initiated an emergency descent, lowering the aircraft from more than 30,000 feet to approximately 9,000 feet in seven to ten minutes—a descent of about 26,900 feet. The aircraft circled over Jeju Island several times before returning to Incheon International Airport, landing safely at approximately 7:40 p.m., three hours after departure. During the rapid descent, 18 passengers experienced adverse medical effects including nosebleeds, low blood pressure, hyperventilation, and eardrum pain. Immediately after landing, 15 passengers were transported to hospitals for treatment; all were eventually discharged. One Taiwanese passenger described the descent as feeling "as if on a roller coaster." The following day, 87 of the original passengers departed on an alternative Korean Air Boeing 737 MAX 8 flight to complete their journey to Taichung.