Transcript for Boeing 737 Max returns to skies following fatal crashes
Now to the boeing-737 max back in the air flying for the first time in the U.S. Since it was grounded for nearly two years after those two devastating crashes. Gio Benitez is at Laguardia airport where the plane has landed safely. Reporter: Hey, Mary. Good morning to you. American is now the first U.S. Airline to put those planes back in the air. The families of those who died are calling on them to take the plane back out of service. This morning after nearly two years, the 737 max is back in the air carrying paying passengers Tuesday for the first time on a flight from Miami to New York. We're flying on a boeing-737 we have the utmost confidence the safety of this aircraft. As a matter of fact, my wife is on board. Reporter: Ashley Rappaport didn't realize she was on a 737, but she was put at ease by the pilot. The deaths on her mind. Were you thinking about those crashes? I was thinking about them when we were taking off, but then as we were midair and everything was fine, and the flight crew was amazing, I was definitely way more at ease. Reporter: The max had B grounded for 20 months after those crashes, sparking a slew of investigations into both Boeing and the FAA. This airplane, I feel is the most scrutinized airplane that we've ever seen, and it needed it. Reporter: ABC news taking the first demo flight on the max just about a month ago. Here in the cockpit, you won't see any changes. The Boeing says it has updated its flight control system, and that is all in the software. Congressional investigators say design flaws, faulty assumptions about pilot responses, and failures by the FAA led to those two crashes. And Boeing and the FAA say the changes to pilot training and the plane itself make it safe to fly, but American says if don't want to fly on this plane, you don't have to. You can change or cancel your flight. They say they will let you know that you are on a max. Mary? Gio, thank you.
This transcript has been automatically generated and may not be 100% accurate.