(Reuters) - The U.S. National Transportation Safety Board released documents on Tuesday morning ahead of hearings into a January mid-air panel blowout of a near new Boeing 737 MAX 9 jet.

The two-day hearing will review issues including 737 manufacturing and inspections, oversight by the Federal Aviation Administration (FAA), and issues surrounding the opening and closing of the door plug involving four missing bolts. Boeing ( BA ) has said no paperwork exists to document the removal of the bolts.