On 5 January 2024, a Boeing 737-9 which had just departed Portland was climbing through 14,800 feet when there was a loud bang followed by a rapid decompression resulting from the loss of a fuselage plug incorrectly installed at an unused door location during completion of the airframe manufacturing process. An emergency was declared and a landing back at Portland was made after a total of twenty minutes airborne. The Investigation is continuing but has found that the fuselage plug involved was installed without being properly secured and noted that the aircraft had only recently been delivered new to the operator.