A United Airlines flight from Fukuoka Airport to Guam experienced a “flap” malfunction shortly after takeoff, prompting an emergency return and landing at Fukuoka Airport. The incident, involving 43 passengers and 6 crew members on Flight 166, caused no injuries. Flaps, crucial for takeoffs and landings by increasing wing surface and lift at lower speeds, were identified as the malfunctioning component. An investigation is underway to determine the cause of the technical issue.