Transcript for American Airlines diverts flight due to cracked windshield

There is a new air scare to tell you about this morning. A flight from Milan to Miami diverted to Canada after the plane's windshield cracked. Reporter: Good morning, more than 200 passengers on this diverted flight are still waiting for a replacement plane to take them back to Miami. These were horrifying moments for passengers on ah an American airlines flight. We dropped from 38,000 feet to 20,000 feet. Reporter: Overnight, this cracked windshield inside the cockpit forcing the aircraft to divert to an airport in Canada. The whole front windshield of the plane was demolished. Sometimes this is caused by the aircraft hitting something. Most often, it's a mechanical failure. A heart on the windshield makes the glass actually break. Reporter: Terrified passengers sharing their trip on social media. Early Saturday morning, a plane carrying Oklahoma City thunder players landed looking like this. Carmelo Anthony posting to Instagram. What possibly could we have hit in the sky at this time of night? Another player saying, it felt like hitting Superman in midair. Dealt that confirming it was birds mid flight that likely left the dent in the front of the plane. Something like this is actually fairly routine in terms of landing the airplane and keeping people safe. Reporter: Passengers on this flight describe those moments as terrifying. Say in a situation whether everybody is likely to panic, the flight crew stayed cool and professional. That's quite heartening. You want that for sure. A lot of other news, to Dr.

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