Rules you need to know before boarding your next flight

HOUSTON, Texas (KTRK) -- The video that left airline passengers stunned, when a passenger targeted for 'involuntary bumping' refused to give up his seat is causing a public relations backlash for United Airlines.

RELATED: Passenger dragged off overbooked United flight

It's also a teachable moment for the flying public.

Houston attorney Benny Agosto has gone up against airlines in court, representing clients injured is aviation accidents.

"In this case, United was within its rights," he said, of removing the passenger. "The Department of Transporation gives the crews the authority to remove people."

David Dao and three other passengers were targeted for 'involuntary bumping,' to make room for four airline crew members also bound for Louisville, to staff a flight there.

"That's allowed because from the moment a crew starts traveling, they're on the clock, and the hours they're permitted to work in a 24 hour period are limited by law. They have to make those flights, and not wait around for the next one, or their plane won't have a crew," said Agosto.

RELATED: Timeline of what passengers experienced aboard the troubled flight

"The problem was in the way the removal was carried out by the Chicago police officer who dragged him from the flight," he said.

Airlines often overbook flights, to compensate for "no-shows" who've already paid for seats but don't make the flight. Often airlines offer passengers incentives, such as vouchers, to take a later flight, and save their ticket for another time.

When no one agrees to that, involuntary bumping comes in.

"Certain passengers are targets to be selected for voluntary bumping," Agosto said. "If you get to the airport and check-in late, that increases your odds. And if you're a low-fare passenger, the odds also go up."

But, there can be money in it for those who are told to leave the plane and take another flight. Though no compensation is given if the traveler is put on another flight that touches down within an hour of the original scheduled arrival, the cost goes up after that.

For an hour or more delay in getting to the destination, it's 200 percent of the one-way ticket price. For two hours or more, it's 400 percent, with a maximum of about $1,300. And Agosto said passengers can get their money by check at the airport.

"They can cash it or choose to hold on to it and pursue more compensation in court."

Then again, the impression left by the video has others calling for federal inquiries into the incident.

"No one who bought and paid for their seat on a plane should be forcibly removed," said Houston Congressman Al Green. "They didn't offer enough money to people to give up their seats," he said. "The decision to take this action started in a board room."

Green and others called for a swift change in policy by the airline.

This afternoon, United's CEO said an investigation has been launched and should be complete by month's end. "We're taking steps to ensure this never happens again," he wrote.

Here is a consumer guide to air travel by the Department of Transportation.

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