Technological failures, system outages and staffing shortages have caused thousands of flight delays and cancellations in recent months, wreaking havoc for travelers across the country and putting a spotlight on transportation officials. According to data from the U.S. Department of Transportation, around 20 percent of flights were delayed last year. While the weather is often to blame, airlines are also frequently at fault.

President Biden and the transportation secretary, Pete Buttigieg, announced a proposed new rule on Monday to compensate passengers affected by carrier-caused slowdowns. Under the proposal, airlines would be required to cover certain expenses for passengers as well as pay them for the inconvenience of flight delays and cancellations.

“I know how frustrated many of you are with the service you get from your U.S. airlines,” Mr. Biden said during the announcement at the White House. “Your time matters. The impact on your life matters.”

What would the change mean for travelers?

Under the new rule, carriers would have to provide passengers with assistance and monetary compensation when the airlines are at fault for cancellations or delays of three hours or more. Beyond free rebooking or refunding the price of the ticket, airlines would have to cover other costs incurred by travelers, such as hotels, meals and ground transportation. Additionally, inconvenienced fliers would be entitled to a payment in the form of cash, miles or travel vouchers.

“When an airline causes a flight cancellation or delay, passengers should not foot the bill,” Mr. Buttigieg said in a statement. The rule would also define “controllable cancellation and delay,” making it harder for airlines to deflect responsibility.

The Department of Transportation is still working out the specifics of how much travelers will be able to expect to be paid for their lost time or how claims will be handled, a spokesperson said in an email.

How is this different from what airlines already offer?

Since last year, most U.S. air carriers have committed to some type of compensation for passengers affected by controllable cancellations and significant delays. All 10 major carriers rebook passengers on the same airline at no additional cost, provide meals or meal vouchers when passengers are left waiting for three hours or more, and — with the exception of Frontier Airlines — furnish complimentary ground transportation and lodging in the case of overnight cancellations away from home.

Yet only two carriers offer customers any kind of compensation for the inconvenience.

Alaska Airlines provides discounts on future flights for delays of more than three hours if they were caused by the carrier. According to the airline’s online policy, affected passengers will receive instructions from Alaska’s airport personnel and an email or letter detailing the amount of the discount.

JetBlue Airways automatically notifies passengers via email if their flight qualifies for compensation and offers travel credit on a sliding scale up to $250, depending on the length of the delay and whether the plane had already boarded.

No major U.S. airlines currently provide cash compensation for disrupted flights.

Is there precedent for this type of rule?

In the European Union, where a similar regulation has been in place since 2004, flight cancellations or lengthy delays may give passengers the right to either a refund or a replacement flight, unless caused by “extraordinary circumstances” like severe weather or political unrest. The rule covers all passengers, regardless of nationality, and routes originating within the European Union — even on U.S. carriers. On flights into E.U. countries, the rule applies only to E.U. carriers.

If flights take off late or are canceled less than 14 days before their scheduled departure, passengers may be entitled to up to 600 euros, or about $660. Passengers may also receive compensation if they’re denied boarding. Claims can be filed with air carriers directly or through an online service like Flightright by providing details about the booking and the cause of the delay or cancellation.

If a flight is delayed overnight, passengers in the European Union may also be entitled to reimbursement for expenses like food, ground transportation and accommodation.

In introducing his proposal, Mr. Biden pointed to research showing that the E.U. policy had made a positive impact on air traffic there. A recent study in the journal Transport Policy concluded that European consumer rights regulations had improved service quality by cutting departure delays and boosting airlines’ on-time performance.

When would the policy take effect?

No one knows for sure, but it isn’t likely to be anytime soon.

Mr. Biden said he hoped the Department of Transportation would “move as quickly as it can to put this new rule in place,” but did not specify a timeline.

The agency is currently working on the official document to announce and explain the proposed new rule. Once that is issued, there will be at least one public comment period, which can last several months and during which there may be public hearings, in person or online. Other agencies might also get involved at later stages of the review and analysis process. The rule could still evolve, or in rare cases, even be scrapped.

For now, passengers can keep track of airline compensation policies at FlightRights.gov.

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