The Federal Aviation Administration is headed for a partial shutdown starting at midnight tonight after Congress left town this afternoon without dealing with an extension of the current FAA authorization set to expire tonight.

The House of Representatives adjourned at 1 p.m. today and will return on Monday; the Senate adjourned at 2:44 p.m. today and will return Monday.

Sen. Richard Durbin (D-IL), the Assistant Majority Leader, asked unanimous consent to pick up the House-passed extension (H.R. 2553), amend it by striking the new Essential Air Service provisions being proposed by the House, and send it back to the House. Republicans objected to the request. Then Sen. Orrin Hatch (R-UT) asked unanimous consent to pass H.R. 2553 without amendment, and Democrats objected. At that point, the Senate adjourned until Monday.

The shutdown will affect some 4,000 FAA employees funded by three appropriation accounts which are drawn exclusively on the Airport and Airway Trust Fund: Facilities and Equipment; Research, Engineering and Development; and Grants-in-Aid to Airports. Programs under those accounts will be suspended starting tomorrow. Funding under the Operations account (which includes all air traffic controllers and aviation safety inspectors) will not be affected.