The Federal Aviation Administration faced a partial shutdown Saturday morning as Congress adjourned Friday without approving a routine stop-gap funding measure amid partisan acrimony.

More than 4,000 FAA workers, 1,000 of them in the Washington region, and tens of thousands of airport construction workers under FAA contract faced immediate furlough. The nation’s air travel system will not be affected, with air traffic controllers remaining on the job and airline operations continuing as normal.

The funding extension would have been the 21st since the FAA’s long-term funding authorization expired in 2007. But House Republicans added provisions to their extension bill that the Senate would not accept.

“I’m very disappointed that Congress adjourned today without passing a clean extension of the FAA bill,” Transportation Secretary Ray LaHood said. “Because of their inaction, states and airports won’t be able to work on their construction projects, and too many people will have to go without a paycheck. This is no way to run the best aviation system in the world.”

Officials said lawmakers would take up the funding issue again Monday. But in the final hours before they headed home Friday, the warring members of Congress accused one another of senseless, inexcusable, astounding behavior, of playing politics and of engaging in doublespeak.

House Transportation Committee Chairman John L. Mica (R-Fla.) said he included the provision to which Democrats in the House and Senate objected out of frustration over the pace of negotiations to reach agreement on long-term FAA funding plans passed by the House and Senate this year.

It cut federal subsidies for air service to several small airports in rural areas.

“In light of the nation’s pending financial disaster and soaring deficits, they couldn’t find a way to cut even a few million dollars by accepting this minor request to reduce outlandish subsidies,” Mica said.

The Senate was infuriated by the provisions because stop-gap extensions normally are bare-form legislation that simply extend funding at current levels while Congress irons out differences over a longer term.

In this case, both the Senate and House long-term FAA funding bills contain language about the rural air service subsidies — called the Essential Air Service program. Congressional staff members have been working on resolving differences between the two bills, and while some House and Senate members have held direct talks, a conference committee has not been convened.

FAA Administrator J. Randolph Babbitt said that the furlough of FAA workers would not affect the safety of air travel, but many of the agency’s functions and its ability to collect $200 million a week in tax revenues that fund its operations will halt.

“The FAA employees who will be furloughed perform critical work for our nation’s aviation system and our economy,” Babbitt said. “These are real people with families who do not deserve to be put out of work during these tough economic times.”

He said that the funding process for airport construction projects will shut down and that FAA funding for states and individual airports will halt.

Employees in 35 states, the District of Columbia and Puerto Rico — scientists, engineers, computer specialists and others — would be furloughed. The FAA said the shutdown would affect construction projects at airports in all 50 states, with more than $5 million at risk for the Metropolitan Washington Airports Authority, which operates Dulles and Reagan National airports.

Democrats and Republicans blamed each other for the shutdown.

“The refusal by the House to extend FAA’s funding authorities is a disservice to the American public and the aviation industry,” said Senate Commerce Committee Chairman John D. Rockefeller IV (W.Va.). “I am disappointed and stunned by their failure. We had negotiated in good faith for four months, but when senior members of the House leadership admitted that they would try to gain political ‘leverage’ over the Senate, they effectively turned the aviation system into a political prop.”

House Republicans said responsibility for the shutdown fell to the Senate.

“It is astounding that the Senate is willing to throw the FAA into chaos in order to protect huge subsidies for a handful of passengers unwilling to drive 90 miles or less to a hub airport,” said Aviation Subcommittee Chairman Tom Petri (R-Wis.). “The Essential Air Service program should not be subsidizing non-essential flights. This is Exhibit A when it comes to wasteful spending, and if the Senate backs away from its own easy reforms like this, how is it ever going to handle the hard cuts?”

The ranking member of the House Transportation Committee, Nick J. Rahall II (D-W.Va.), whose differences with Mica have become more pronounced in recent weeks, said the blame lay with the House.

“By senselessly shutting down the FAA tonight at midnight, the House Republican leadership is willing to lay off tens of thousands of middle-class American construction workers and jeopardize billions of dollars in airport construction simply to score a few political points for tea party extremists,” Rahall said.

“Republicans are holding hostage America’s aviation system with their ‘my way or the runway’ shotgun approach to negotiating a long-term FAA reauthorization.”