Tonight the troubling discovery by United Airlines after a piece of an Alaska Airlines plane blew off in light.

United saying it found loose bolts during inspections on grounded 7-7 Max9 planes after the NTSB recovered the 63 pound door plug

that flew off an Alaska Airlines plane at 16,000 feet, the rupture sucking out headrest, seat cushions, even passenger cell phones, and the growing

questions about the warning lights on three previous flights.

Also tonight the new storm on the move, blizzard conditions in the Central U.S.

Flash flood threats in the northeast on the heels of the first major winter blast of

2024. Al Roker is timing it out. The hotel explosion in Texas, windows and debris blown

into the street, multiple injuries, what we've learned. Defense Secretary Lloyd Austin

under fire after he failed for days to disclose he was hospitalized to the president and the public.

What the White House is saying as Republicans call for him to be fired and did he break any laws the first

US moonlander mission in more than 50 years in danger what happened after the

unmanned launch and the exclusive Olympic gold medalist Mary Lou Retton

her first interview since her life-threatening health battle.

This is NBC Nightly News with Lester Holt.

Good evening and welcome everyone.

There are major developments tonight in the investigation of that Alaska Airlines

Boeing 737 Max Nine jet that suffered a mid-air depressurization and

loss of an entire door window assembly called a door plug over Portland Oregon on

Friday.

United Airlines, the only other U.S. operator of the Max-9 reports inspections of its aircraft

have found instances of issues in the door plugs, including bolts that needed additional tightening.

Also tonight we're getting our first look at the door plug section that's separated from

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