Inside Delta's emergency response for Sandy

(CBS News) Four days after superstorm Sandy, the situation's much better in the air than on the ground in New York. Air travel in the northeast is nearly back to normal Friday, after this week's cancellations of some 20,000 flights.

For all the knocks on the flying experience, the airline industry has learned from past weather disasters and how to better prepare for them. To find out what's changed, CBS News asked Delta Air Lines for a backstage tour of its operations and emergency plan.

Complete coverage of superstorm Sandy

When a Delta flight from Richmond landed in New York Thursday morning, LaGuardia Airport was back in business after a three-day hurricane shutdown. The next 14 flights to touch down were all Delta's too -- made possible because of the people in one room 900 miles south in Atlanta. It's the room where mainline operations of Delta are conducted.

Dave Holtz, a 33-year Delta veteran, directs the Operations Control Center, or OCC. It's massive, about the size of a football field. In it, 650 employees control Delta's 1,500 daily flights around the clock. A week ago, Holtz and his team began phasing in Delta's emergency response -- three days before Sandy made landfall. Holtz said, "That's the key to us here, that's the part that the customer doesn't see. That's the part our folks in the field don't see necessarily is how we're getting those ... dominoes all set up, so that when we do take them down, it's orderly. We know exactly where they're going, and it's clean."

For starters, Delta turned to a secret weapon: its in-house team of 27 meteorologists. They helped pinpoint which airports were in Sandy's bull's-eye.

Mike Heying is one of those meterologists.

Asked what information is looked for the most, Holtz said it's for detailing the forecast. "(We're looking for) narrowing it down to what we're going to see," he said. "Not giving us that broad brush of, 'Well, somewhere between Washington, D.C. and Boston it's going to hit.'"

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Heying was confident Sandy would come ashore south of New York City, but batter the city's airports the worst.

Asked if he was nervous for the airline, Heying said, "No. Not at all. ... We had a plan ready to go."

Holtz set that plan in motion over the weekend, notifying passengers which flights would be canceled through Wednesday, and waiving change fees. They also repositioned 120 planes out of harm's way in five Delta hub cities, and flew extra employees into New York before the hurricane struck.

The airline canceled flights earlier than they probably had to, but looked to get back up to speed once the storm passed as quickly as possible. Holtz said, "When you take it down in an orderly, predictable fashion for customers and for us here in the operations center, you're able to bring it back that exact same way."

Sandy closed 15 airports in the northeast, including all three that service New York City. Delta had canceled 1,445 flights, and some passengers were upset. But you didn't see an image from past storms: terminals packed with stranded travelers.

One of the goals with Sandy was to prevent turning the airports needlessly into a massive shelter of grumpy, tired, frustrated people. Holtz quipped, "We try to keep all the grumpy frustrated people in my office. Nobody benefits by having people in the airport who can't fly. There's no reason for that."

As New York ground crews pumped a foot and a half of water from runways, Holtz and his Atlanta team coordinated with airport administrators and emergency officials.

On Thursday morning, Holtz showed CBS News the last New York airport -- LaGuardia -- coming back to life, a depiction on a computer screen of green lights showing Delta planes.

Holtz said, "The whole thing becomes triage if it's not taken down properly. As you start up, in this case, orderly shutdown, orderly start-up."

Watch Mark Strassmann's full report in the video above.