A Korean Air passenger flight departing from the U.S. territory of Guam returned shortly after takeoff due to warning lights.
According to the airline industry on the 10th, at around 5 p.m. local time on the 9th, an oil warning light illuminated in the number 2 engine of flight KE422 (B777-300) approximately 30 minutes after taking off from Guam. At the time, the aircraft had reached an altitude of 12,000 feet (about 3.66 km) before returning to Guam airport.
Korean Air had all 330 passengers disembark and transferred them to a replacement flight from Korea. The replacement flight departed from Guam at 2:43 a.m. and arrived at Incheon International Airport at 5:56 a.m., 9 hours and 43 minutes later than originally scheduled.
Regarding the aircraft in question, an engine oil inspection is underway to determine the reason for the warning lights. Korean Air noted that 'if an oil warning light (check message) is displayed, a maintenance check is mandatory for safety, so a replacement flight was arranged immediately, regardless of whether there is an actual issue.'