It has been a very, very rough week in the aviation business and especially for passengers.

Delta Airlines finally has most of its operations back to normal today after days of delays and thousands of flight cancellations connected to a

tech outage that angered travelers and gave the airline a black eye. Delta's

response is now being investigated by the Department of Transportation.

Southwest Airlines is also being investigated by the federal government for a string of

near-miss incidents involving its aircraft.

Separately, Southwest also announced today

that it's finally going to move to an assigned seating

system for the first time in its history.

Our aviation correspondent, Miles O'Brien, is here to catch us up on the latest.

Miles, it's always great to see you.

So let's start with this big move from Southwest.

They are ending the cattle call boarding system.

What's behind the big change?

Well, this is about great expectations that have fallen a little bit.

Right now, Southwest is profitable, but not as profitable as it has been over the course of many years, and

it is not meeting the expectations of Wall Street.

And so there are activists investors in the midst insisting that the management

changed the way it does business. But it's interesting if you look at Southwest

history this is about the most profitable airline ever year after year of profitability even after 9-11

during the middle of recessions in the 90s when fuel prices were high they had a

hedge fund for fuel and managed to get around that they've always done very well with that, having a very

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