CHICAGO (AP) _ After years of bitter feuding with its unions, United Airlines may have entered an era of peace in the workplace, analysts said Friday, a day after the giant air carrier came to contract terms with its machinists.

Members of the International Association of Machinists still must ratify the contract, which covers 27,000 workers and runs through November 1994. But machinists' assistant general chairman Ken Pheide said late Thursday the negotiating committee would recommend the contract to the rank and file.

Union members have until Dec. 23 to ratify the contract, United spokeswoman Lynn Martenstein said Friday. The union did not return repeated phone calls.

United and the union had been negotiating virtually non-stop since Monday. The union could have voted to strike immediately if no agreement was reached by 12:01 a.m. EST Friday.

Terms of the contract were not released. But the tentative agreement put an end to concerns the air carrier would be idled by a strike at a critical time of year and marks the first time in years that the airline can bask in relative accord with its unions.

''United's in a new era: labor peace,'' said Robert Decker, an airline analyst for Duff & Phelps.MCM.

United has wrangled bitterly with its unions in recent years, a struggle highlighted by an arduous and ultimately failed attempt at a buyout by its unions.

The airline now has agreements in place with its pilots, flight attendants and machinists.

''It's no coincidence,'' said Decker. ''The takeover attempts at United Airlines disrupted the contract negotiations... With that to the side, you could sit down and hammer out labor contracts.''

Barbara Beyer, airline consultant for Chicago-based Avmark Inc., said the airline could have ill-afforded a strike in this economic climate, particularly with the peak holiday season about to begin.

''It's their last opportunity to make a nickel before the year closes,'' she said.

The airline's parent company, UAL Corp., last week cited the weak U.S. economy and discount pricing in saying it would post record losses for both the fourth quarter and the year.

''Secondly, the loss of the good will from their customer base would be tremendous,'' said Beyer. ''People tend not to be sympathetic if they can't get home to Mom.''

The union could also have suffered from a holiday strike, said Nick Salvatore, a labor historian at Cornell University's School of Industrial and Labor Relations.

The public might regard such a strike as ''narrowly self-interested. That's the last thing labor needs at this point,'' Salvatore said.