Updated at 11:20 a.m. ET

The CEO of United Airlines is in the hot seat on Capitol Hill this morning, answering pointed questions from members of Congress about last month's incident in which a United passenger was dragged off a plane.

"It was a mistake of epic proportions," United CEO Oscar Munoz told representatives, as he explained how United has changed its rules moving forward. "In hindsight, clearly our policies broke down."

Executives from other airlines are there, too, as Congress examines customer service problems across the commercial aviation industry and considers legislation to better protect airline passengers.

"It's shameful that an event like the one that we had at United needs to drive this conversation," Munoz said.

Munoz is appearing before the House Transportation Committee, along with the airline's president, Scott Kirby, to try to explain why the airline needed to bump passengers from a flight heading to Louisville, Ky., from Chicago after they'd already been seated, and why United called on O'Hare airport security officers to remove the passenger who refused to give up his seat.

Cellphone video shows the officers violently pulling 69-year-old Dr. David Dao of Kentucky out of his seat and then dragging him up the aisle and off the plane.

Dao suffered a concussion and a broken nose and lost two teeth. His attorney says he may need surgery because of his injuries. Dao reached a settlement with United last week for an undisclosed amount.

Munoz has apologized repeatedly for the incident and for his own initial response, which was criticized as tone deaf when he apologized for having to "re-accommodate" the passenger.

Last week, the airline announced several policy changes to prevent such incidents from happening again. One change is that United will reduce over-booking of flights in order to limit the need to "bump" passengers to a later flight.

When it does overbook, United will now offer up to $10,000 to passengers who volunteer to be bumped. The intention is to limit the need to involuntarily bump passengers, as happened in the April 9 dragging incident.

United also says that the airline will no longer call on airport police or other law enforcement personnel to handle these kinds of matters, unless safety and security are at risk.

Others scheduled to testify at the hearing, which began at 9:30 a.m. ET, include Joseph Sprague, senior vice president of external relations for Alaska Airlines; Bob Jordan, executive vice president and chief commercial officer at Southwest Airlines; Kerry Philipovitch, senior vice president of customer experience at American Airlines; and William McGee, an aviation consultant with Consumers Union

Philipovitch apologized for a recent incident on American Airlines on April 21 in which a flight attendant and a passenger clashed over a stroller.

"It's important for American to take responsibility when we don't handle things well," she said. "There's no question that we can do better."

Congress is considering legislation to better protect airline passengers.

Among the bills recently introduced in the wake of the United Airlines incident:

  • The BOARD (Bumping on Overbooked Airplanes Requires Dealing) Fairly act, introduced by Chicago-area Democratic Rep. Jan Schakowsky, which would prohibit airlines from bumping passengers against their will, ever.
  • The SEAT (Secure Equity in Airline Transportation) Act, which would prevent airlines from removing a customer from his or her seat to make room for another passenger or an airline employee, introduced by Republican Rep. Neal Dunn of Florida.
  • The "Customers, Not Cargo" Act, which would also prohibit airlines from bumping passengers from overbooked flights after they're seated on the plane, introduced by Sen. Chris Van Hollen, D-Md.
  • The TICKETS (Transparency, Improvements and Compensation to Keep Every Ticketholder Safe) Act, proposed by Democratic Sens. Maggie Hassan of New Hampshire and Brian Schatz of Hawaii, which in addition to prohibiting airlines from bumping passengers who have already boarded, would also lift the federal cap on the amount of compensation airlines have to pay bumped passengers.
  • The Passenger Bill of Rights, which was introduced last year by Sen. Richard Blumenthal, D-Ct. It would expand and update the "Passenger Bill or Rights" implemented by the Department of Transportation during the Obama administration.

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