Your flight is stuck on the tarmac. What do airlines owe you?

U.S. airports fell into chaos last week as a CrowdStrike outage led approximately 46,000 flights to be canceled worldwide. Thousands of Delta flights continue to be affected, provoking a Department of Transportation investigation and adding to what already was a summer of flight delays.

But while delays often are miserable, they can be even more so when you’re waiting on the tarmac, as some of the outage-affected passengers said they were. It doesn’t help that, in a summer of extreme and dangerous heat, planes can’t cool cabins on the ground as well as they can in the sky.

If your flight is stuck on the tarmac past a certain point, airlines may owe you. But there’s a catch.

The protections for U.S. airline passengers are “rudimentary” compared to in Europe, said Eric Napoli, the chief legal officer at claims management company AirHelp. “The best you’re going to get is what airlines want to offer you in the terms and conditions you have for that airline.”

You’ll have to advocate for yourself.

Your basic rights while on the tarmac

Tarmac delays have shortened significantly since the Transportation Department established customer-protection rules for delays, said William McGee, a senior fellow for aviation and travel at the American Economic Liberties Project. But some tarmac stops still can drag maddeningly on.

Depending on how long you’re stuck on the tarmac, airlines in the United States have certain obligations.

Per Department of Transportation rules, at the two-hour mark, airlines must provide their passengers with food, water, “comfortable” cabin temperatures, access to functioning toilets and medical assistance, if needed. After that - before three hours on the tarmac for domestic flights, and before four for international flights - an aircraft must provide customers the option to deplane. The exception to this rule, Napoli said, is if a safety issue is preventing the plane from returning to the gate.

The same tarmac rules apply for arriving planes. If travelers are not provided with these essential provisions, Napoli recommends filing a complaint with the airline as soon as possible.

Airlines’ policies for flight delays

Some airlines that provide food, hotel or transportation vouchers or flight credits for other sorts of delays would provide the same for a tarmac delay, as long as it falls within their specific guidelines.

To find your airline’s policies, check the Transportation Department’s Airline Cancellation and Delay Dashboard, which compiles compensation and rights information from 10 U.S. carriers. The dashboard lists which airlines give a travel credit or voucher when delays last more than three hours (JetBlue, Southwest and Alaska) and which provide hotel accommodation and transportation in the case of significant delays (all but Frontier). The Transportation Department does not define “significant delays” worthy of refunding, however, so travelers who believe they’re eligible must file a complaint with their airline on a case-by-case basis.

McGee also recommended that passengers download their airline’s contract of carriage, documents that serve as contracts between U.S. airlines and their passengers. Contracts of carriage can be difficult to understand, but knowing your rights helps you appeal for what you deserve.

“You have to do a little homework. I wish I could say it was easy … but it’s not, in the United States,” McGee said.

How to get what airlines owe

Regardless of the problem, whether delay or cancellation, contact airline customer service quickly. Especially during mass disruptions like the CrowdStrike outage, beating the rush to ask for help can be the difference between getting timely help and waiting hours or days for a response.

The best way to reach customer service, experts say, is in person or over the phone. Talking to a real person - even if it requires a long hold time - means you can more directly insist upon your rights, rather than argue with a chatbot.