I knew it was UAL going thru the back door to keep its regional at IAD an= d stop the low fare start-up. I hope this hurts thier chance and the $1.= 6B itstring to get from the Gov. = Judge blocks Mesa Air consent solicitation effort = = = = Thursday December 18, 8:18 PM EST = NEW YORK, Dec 18 (Reuters) - A U.S. District Court judge on Thursday issu= ed a preliminary injunction blocking Mesa Air Group Inc.'s (MESA) effort = to replace Atlantic Coast Airlines' (ACAI) board as part of its unsolicit= ed takeover attempt of the regional airline. Meanwhile, Atlantic Coast said the U.S. Justice Department has opened an = antitrust probe into Mesa's $495 million takeover offer, joining a simila= r probe by District of Columbia antitrust officials. A Mesa spokeswoman was not immediately available to comment. But the two events represent a setback in the attempt by Phoenix-based Me= sa to acquire Atlantic Coast, of Dulles, Virginia, and form a more powerf= ul regional airline. The injunction was handed down by U.S. District Court Judge Rosemary Coll= yer, who determined Atlantic Air had raised enough antitrust concerns per= taining to Mesa's takeover bid that its lawsuit against Mesa should be al= lowed to continue, court documents showed. = Collyer, a judge in the U.S. District Court for the District of Columbia,= said a deal struck last month between Mesa and UAL Corp.(UALAQ), the par= ent company of United Airlines, was of particular concern. Specifically, Collyer said the deal, which would permit Mesa to provide r= egional service for United Airlines should it acquire Atlantic Coast, mig= ht violate the Sherman Act because it potentially restrains Atlantic Air'= s ability to launch a low-cost competitor to United. Earlier this month, Mesa Air filed a consent solicitation seeking shareho= lder support to replace Atlantic Coast's board with its own nominees. Mesa Air Chairman and Chief Executive Jonathan Ornstein said on Thursday,= speaking at the Wings Club before the decision was handed down, that sho= uld his airline lose its motion to dismiss the preliminary injunction req= uest, it would have to evaluate whether to appeal or not. The airline has promised to launch a hostile tender offer to acquire Atla= ntic Coast, but to date has not done so. Mesa has offered to acquire Atlantic Coast for 0.9 of a share of its stoc= k, valuing the airline at $10.91, based on closing prices on Thursday. At= lantic Coast has repeatedly rebuffed that offer. On Thursday, Atlantic Coast's stock closed at $10.45, up 5 cents on Nasda= q. Mesa's stock ended at $12.12, up 16 cents, on Nasdaq. = =A92003 Reuters Limited. = Roger EWROPS