AMNA NAWAZ: Welcome to the "News Hour."

The Federal Aviation Administration laid out a plan today to cut as much as 10 percent of flights operating out of 40 major airports, starting at a lower-level tomorrow and ramping up over the coming week.

Today, airlines already preemptively canceled hundreds of flights in response.

Many of the airports in the plan are among the nation's busiest, including Atlanta, Chicago, Dallas, Houston, Denver, Los Angeles, and the New York and Washington, D.C., metro areas.

The Trump administration said the move was triggered by the government shutdown and is necessary for safety.

Airports have faced delays, as air traffic controllers working without pay have been calling in sick.

Staff shortages have also led to longer security lines in Houston and elsewhere.

Transportation Secretary Sean Duffy explained his reasoning yesterday.

SEAN DUFFY, U.S.

Transportation Secretary: I'm concerned about disrupting people's travel.

We're coming into a weekend.

That doesn't -- listen, I travel a lot.

We are concerned about that.

But we had to have a gut check of, what is our job?

Is it to make sure there's minimal delays or minimal cancellations or is our job to make sure we make the hard decisions to continue to keep the airspace safe?

AMNA NAWAZ: Joining me now to break all of this down is David Shepardson of Reuters News.

Good to see you.

DAVID SHEPARDSON, Reuters: Thank you.

AMNA NAWAZ: Let's just start with this.

Have we ever seen anything like this before in a government shutdown?

DAVID SHEPARDSON: It's unprecedented.

And certainly in the 2019 shutdown, if you remember, that went about this level 35 days, and that was credited, that shutdown was credited with the end by the big disruption in aviation caused by controllers calling in sick in New York and D.C.

But the government did not take this extraordinary step of ordering the airlines to cut flights during that shutdown.

AMNA NAWAZ: And we're seeing airlines already taking steps to cancel some of those.

What else are you hearing from them about how they're going to do this and their concerns?

DAVID SHEPARDSON: Well, it's been a pretty rough 24 hours for them, right, because this came out roughly 4:00 yesterday and they have been struggling to figure out, how do we cancel flights?

Now, initially, the government said it was going to be 10 percent Friday.

Instead, it's going to be ramped up, 4 percent Friday through Monday, rising to 6, 8.

And then it would hit that 10 percent figure a week from tomorrow.

Now, 4 percent is still challenging.

And, as you said, a bunch of airlines have already started pre-canceling flights.

But that's manageable versus 10 percent, which is going to be more difficult and one of the reasons the airlines argued for more time to get to that higher level.

AMNA NAWAZ: What are we talking about in terms of the scale of disruption, the number of flights potentially disrupted, even from 4 up to 10 percent?

DAVID SHEPARDSON: So that 4 percent figure, we're seeing roughly 700, 800 flights from the four major carriers.

American Said 220, Delta about 170, around the same number for United, Southwest at 120.

So it's a big number.

Now, luckily, this is not a huge travel weekend.

Yes, it's Veterans Day, but it's not Thanksgiving, it's not Christmas, it's not spring break.

So there is some slack in the system.

And so airlines feel confident they can handle it, they can reroute people.

You're going to get this automatic notification.

Hopefully, if your flight's canceled, you got another one.

But it's like having a mini-snowstorm, if you will, in 40 airports, and the airlines don't have the flexibility they would typically, say American,.

There's a snowstorm in Chicago, maybe you up flights in Dallas to address this.

This is 10 percent -- I'm sorry, 4 percent to start across the board, so a little more restrictive in terms of how you deal with that.

AMNA NAWAZ: And the argument here is safety, right?

So if they have that 4 percent reduction, does that actually alleviate enough pressure on air traffic controllers to make it safe?

Does 4 percent get you there, or does 10 percent?

DAVID SHEPARDSON: Great question.

So let's go back to Halloween, right?

We had a major disruption, right?

In the New York area, about 80 percent of the controllers did not show up.

At one point, there was only one controller in a center.

It was -- there were many, many delays, and luckily it was Halloween, where there's less traffic than normal.

It wasn't as bad as it could have been.

But that, I think, has set off concerns.

And, this week, the FAA administers said 20 to 40 percent of controllers are not showing up every day.

Now, what the FAA has been doing before now is slowing flights.

And sometimes it would result in cancellations primarily.

We're going to slow it down.

We're going to have fewer flights per hour per runway at busy airports to address it.

This is taking a more aggressive step at the top.

Now, there's a dispute.

People like the NTSB chair, Jennifer Homendy, say, this is great.

We need to do this.

Democrats like Rick Larsen, who's a top Democrat on the Transportation Committee, says, I want to see the data.

What exactly prompted this and why now?

And there are some suspicions that this came the day that President Trump said the shutdown might have been partially to blame for the losses in the election, and, therefore, is politics involved?

AMNA NAWAZ: Well, what do we know about that?

Because the fact that the administration changed the plan from the more aggressive 10 percent right away kind of dialed it back to 4 percent... DAVID SHEPARDSON: Right.

AMNA NAWAZ: ... there is the allegation that this is about and adding pressure to Democrats to end the shutdown.

DAVID SHEPARDSON: At a minimum, it sure looks like this is on the fly.

And airlines have been really frustrated, I think, trying to deal with this, I mean, starting with 10, going down to 4.

Remember, yesterday it was going to be 4, then 5 and 6 percent.

So it's changed yet again.

And this is still a draft order.

We don't know for certain that 4 percent is going to stick.

I mean, it seems likely, but we got to see the final paper.

So I do think, at a minimum, airlines and some Democrats are saying, why now, why is it in such flux, and why wasn't this plan more firmly laid out before it got announced?

On the other hand, Secretary Duffy would say, look, this has happened before, before the near -- before the collision in DCA, when six people died, there were thousands of reports of near misses.

Let's get ahead of it.

And we do know the controllers are under severe stress.

They're already working six-day workweeks and 10-hour days before this, because of low staffing.

And they are under stress.

They haven't been paid for five weeks.

AMNA NAWAZ: Thirty seconds left.

What should consumers expect in the day and days ahead because of this?

DAVID SHEPARDSON: I think you're going to be OK.

You're going to get on your flights.

You might have a delay.

You might get a cancellation, but still, 4 percent, that's one out of 25 flights.

So hopefully you're one of the 24 of the 25.

International flights will be fine.

But check with the airlines and do all the things you're supposed to do.

Check the Web site.

Go to the -- go to the -- get there early and hopefully everything will be OK.

AMNA NAWAZ: All right.

DAVID SHEPARDSON: And be patient.

And be nice to people at the airport, especially those who are not getting paid.

AMNA NAWAZ: That is always good advice.

David Shepardson of Reuters, great to see you.

Thank you.

DAVID SHEPARDSON: Thank you.