In February, a Delta plane took off from Atlanta, bound for South Carolina.

At first, everything seemed fine.

But minutes after takeoff, plumes of white smoke entered the cabin.

Passengers started pulling out their phones and taking video.

We on a f-smoked out that plane.

Look at this shi-brough.

It got so thick that, you know, in the official report,

they talk about, you know, flight attendants not being able to see more than two or three rows in front of them.

That's our colleague Benjamin Katz. He covers the airline industry.

In the video, there's a recording that really struck me when I listened to it.

Ladies and gentlemen, please breathe through your clothing. Stay low.

I mean, the passengers were, we've freaked out, you know, really, really affected and just scared, you know.

How could this happen?

Like, what happened?

What is going on here?

The flight crew radioed in an emergency, and the plane was diverted back to Atlanta.

Videos show passengers evacuating onto the tarmac, climbing out over the aircraft's wings

and exiting down the inflatable emergency slides.

In the airline industry, there's a term for what happened on that Delta flight.

It's called a fume event.

A delta spokesman said the company was cooperating with a national transportation safety board review of the incident.

For most of this year, Ben and a team of Wall Street Journal reporters have been digging into fume events like this.

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