The U.S. National Transportation Safety Board announced on that Boeing violated relevant regulations by disclosing non-public information related to the investigation of the Boeing 737 MAX9 incident to the media, and therefore announced sanctions against Boeing. Boeing will no longer have access to relevant investigative information from the National Transportation Safety Board. On January 5th, a Boeing 737 MAX9 aircraft of Alaska Airlines in the United States encountered an incident shortly after takeoff, with a door plug on the side of the cabin falling off. The U.S. Federal Aviation Administration subsequently requested Boeing to submit an improved quality control plan for incidents such as door plug falling off, and at the same time prohibited Boeing from increasing production of the 737 MAX series aircraft.