Transportation Secretary Ray LaHood says the sequester will have “a very serious impact” on transportation services throughout the U.S., specifically on aviation. (The Washington Post)

More than 100 air traffic control towers could be closed and travelers could expect lengthy flight delays beginning in April, the White House warned Friday in its latest bid to raise public alarm over the mandatory spending cuts set to kick in next week.

Transportation Secretary Ray LaHood vowed that airline security would not be compromised, but he emphasized that the Federal Aviation Administration would have no alternative but to furlough thousands of employees as it seeks to slash $600 million.

LaHood’s surprise appearance in the White House briefing room aimed to put a spotlight on the real-world consequences of the political standoff over the across-the-board spending cuts, known as the sequester that will take effect next Friday.

Even as LaHood painted a dire picture, a Pew Research Center/USA Today poll released Thursday shows that most Americans have heard little to nothing about the potential cuts. Only 27 percent said they had heard “a lot” about them.

The White House has sought to change that this week with a public relations campaign that included President Obama’s appearance Tuesday with emergency medical workers and an announcement by the Pentagon that it would furlough up to 800,000 civilian employees one day a week.

You’ve heard the word “sequester” mentioned by politicians a lot lately. The Washington Post’s Ed O’Keefe explains what the term means, and why it matters. (The Washington Post)

But it was the specter of widespread travel delays — up to 90 minutes during peak flight periods — that the White House hoped would rally public opinion and put pressure on Republican lawmakers.

“Your phones are going to start ringing off the hook when these people are delayed at airports,” said LaHood, a former GOP congressman from Illinois. “Nobody likes a delay. Nobody likes waiting in line.”

The sequester was put into motion by the August 2011 debt-ceiling deal, and there have been few signs of progress in negotiations to avert them. Obama has proposed a mix of budget cuts and new revenue through closing corporate loopholes, but Republicans have said they will not raise taxes and instead have pushed to cut federal health spending.

During a photo op in the Oval Office after a meeting with Japanese Prime Minister Shinzo Abe, the president said Friday that the impact of the budget cuts would slow growth in an already soft economy.

“It also means that we are not going to be driving down unemployment as quickly as we should,” Obama said. He added that his fellow world leaders understand that drastic budget cuts are the “wrong prescription” for the U.S. economy.

“I don’t need to persuade world leaders of that,” Obama said. “I’ve got to persuade member of Congress, and that can be harder sometimes.”

House Republicans continued to blame Obama for the sequester, which the White House proposed in 2011 and Congress approved.

Several Republicans who serve as leaders on transportation policy released a statement Friday accusing the administration of exaggerating the impact of the scheduled cuts on air travel.

“We are disappointed by the Administration creating alarm about sequestration’s impact on aviation,” said the statement from Sen. John Thune (S.D.) and Reps. Bill Shuster (Pa.) and Frank A. LoBiondo (N.J.). “Before jumping to the conclusion that furloughs must be implemented, the Administration and the agency need to sharpen their pencils and consider all the options. Prematurely outlining the potential impacts before identifying other savings is not helpful.”

They added that the FAA is “well positioned to absorb spending reductions without compromising the safety or efficiency of the National Airspace System.”

Sen. Tom Coburn (R-Okla.) also sent a letter to the White House budget office asking for information about the administration’s “Connecting to Your Community” tour, in which agency officials are scheduled to appear in 100 cities to help with local projects.

“If Washington is truly cutting spending on missions many consider vital, how can we at the same time promise and promote more financial assistance, much less afford this mammoth 100 city cross country tour?” Coburn wrote.

A White House official said the tour mostly involves federal officials in regional offices meeting with municipal leaders, with Washington-based staff traveling only infrequently.

LaHood disagreed with suggestions that the airport warnings amounted to scare tactics. He said the vast majority of the FAA’s 47,000 employees would probably be furloughed one day in each two-week pay period until the end of the fiscal year in September.

More than 100 air traffic control towers could be closed, including two in Virginia — Manassas and Lynchburg regional airports — and five in Maryland, including Frederick Municipal Airport.

Also on the list: Southern Wisconsin Regional Airport in Janesville — home of Rep. Paul Ryan (R), chairman of the House Budget Committee and a champion of spending cuts. Overnight shifts at more than 60 towers across the country could also be eliminated.

“If we can’t get on the plane within 30, 40, 50 minutes after going through, you know what happens?” LaHood said. “They start calling their member of Congress.”

Roger Dow, president and chief executive of the U.S. Travel Association, said the threat of long security lines and flight delays could make travel “the face” of the sequester cuts.

The association has launched a mobile messaging campaign, urging travelers to text the word “DELAYED” to 877-877. In response, they will be connected with their local member of Congress.

“There is absolutely no excuse for travelers in one of the world’s most advanced nations to suffer through a travel process that wastes their precious time and resources,” Dow said.

At the White House, Democratic governors who met with Obama ahead of this weekend’s National Governors Association conference decried the impact of the sequester on their states, saying federal funding cuts will affect the National Guard, firefighters, police and teachers.

“This is another kick in the teeth by Republicans to the middle class of America,” said Connecticut Gov. Dan Malloy (D).

Travelers will also probably face delays getting through airport security, officials said. Homeland Security Secretary Janet Napolitano has said the cuts would force the Transportation Security Administration to initiate a hiring freeze for all transportation security officer positions in March, eliminate overtime and furlough its 50,000 officers for up to seven days.

“Sequester will cripple air transportation, causing ripple effects across the economy and costing us jobs we can’t afford to lose,” said Sen. Barbara A. Mikulski (D-Md.). “These are real impacts in real communities with real consequences.”

Airlines are preparing for possible disruptions in their schedules. Airlines for America, a trade group for the nation’s leading airlines, said it will meet with the FAA and member airlines to plan for potential cutbacks.

Though LaHood said he hoped his roots in the GOP would help persuade the two parties to reach a compromise, much of Washington appeared to be bracing for the worst.

Asked if he still thought there was time to reach a deal, Obama replied, “Hope springs eternal.”

Luz Lazo contributed to this report.

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