The CEOs of Southwest Airlines, JetBlue Airways, and American Airlines on Thursday publicly condemned the U.S. government shutdown and called on America’s political leaders to resolve the situation immediately to prevent widespread damage to the country’s air travel system.

In addition to the long security-checkpoint queues and flight delays affecting all U.S. carriers following the furloughing of hundreds of thousands of federal employees, Southwest Airlines has felt particularly harsh effects from the shutdown because those FAA employees still working—all without pay—concentrate only on critical safety-related tasks. As a result, FAA inspectors remain unable to validate Southwest’s operational ETOPS performance, the final step in the certification process the carrier must complete before it can launch service from four mainland U.S. cities to four airports in Hawaii, according to Southwest’s president Tom Nealon.

“The FAA has approved our program; all we need to do is to prove to them that we can execute it,” said Nealon during the airline’s 2018 year-end earnings conference call. Both Southwest and the FAA want to complete the certification but the current safety-work-only mandate prevents the FAA inspectors from doing their jobs, he said. “If the shutdown ends within a week, we have a reasonable chance of beginning service [to Hawaii] in the first quarter of 2019,” reported Nealon. “If not, it will be in the second quarter.”

Southwest expects its new Hawaii routes to account for half of its entire 5 percent forecast 2019 capacity growth, so the longer the shutdown continues the greater the schedule effects on Southwest will be, said CEO Gary Kelly.

“I will sum it up in a word: it’s maddening,” said Kelly. “I’ll also state the obvious here: no one can predict the effects it will have if it continues. Everyone needs to be on notice and on guard that this shutdown will hurt the economy and it could harm air travel.” As for Southwest itself, Kelly promised to limit the financial damage. “We will do everything we can to find a way to work through this slop,” he said. “We will continue to work through the effects it is having now and contain the damage and keep our finances strong.” Southwest has lost $10 million to $15 million in revenue in January due to the shutdown.

Speaking during JetBlue Airways’ 2018 earnings conference call, CEO Robin Hayes reported little short-term effect on his airline’s day-to-day operations, but he warned that circumstances could turn dire quickly. “At this point, we have not seen a significant impact to our operations, nor our bookings,” said Hayes. “However, we are increasingly concerned about the shutdown’s consequences for convenient and efficient air travel and for the economy overall. We are close to a tipping point, as many of those [federal] employees are about to miss a second paycheck. Our crewmembers and customers are likely to face extended security lines, flight delays, and even cancellations and the longer this goes on the longer it will take for the air transport infrastructure to rebound. Our nation’s leaders must find a resolution for this stalemate today.”

Responding to analysts’ questions during American Airlines’ 2018 earnings call, CEO Doug Parker said while the FAA and TSA haven’t let the shutdown affect the safety and security of the U.S. air transport system, it has created inefficiency. “It tends to [produce] long lines at security, but with the same level of security, [as well as] larger separation of aircraft, and delays,” he said. “Those are things of real concern to us and that’s what we fear.”