CHICAGO (AP) _ Representatives of UAL Corp.'s non-union employees met Monday with the chief of the union group trying to buy the airline company in hopes of avoiding a setback in the buyout effort.

The meeting in Chicago between Gerald Greenwald and leaders of the non- contract group was their second within a week, said Stephen Fraidin, a lawyer for the non-union workers.

It followed a stinging statement Sunday by the 26,000 non-contract workers expressing disappointment that the union group had not accepted proposed wage concessions and benefit modifications under which the non-contract workers could support the buyout plan.

The unions do not consider the non-union group's support essential to the proposed $4.54 billion deal for the parent of United Airlines. But opposition by the non-contract group, which accounts for more than one-third of UAL's 71,500 employees, could complicate the unions' attempts to raise financing.

The buyout group's contract to buy UAL will lapse if financing is not obtained by Aug. 10. If financing is secured, the group would have until the end of the year to close the deal.

''We continue to be hopeful that an agreement can be reached,'' Fraidin said in a telephone interview.

Greenwald, formerly vice chairman of Chrysler Corp., agreed earlier this month to head the buyout group composed of United's pilots, flight attendants and Machinists unions.

If they are successful, Greenwald would become chairman and chief executive of UAL, which is based near Chicago in Elk Grove Village.

The non-contract employees said in a news release Sunday they had developed a package of wage concessions, benefit modifications and governance agreements during discussions with the United Employee Acquisition Corp. - the entity formed by the unions to handle the proposed buyout.

But the acquisition firm has not agreed to the package, a news release from System Roundtable said.

System Roundtable is an organization of representatives from the different groups of non-contract employees. It effectively has become the non-contract employees' bargaining agent in the buyout plan.

''If this package is not agreed to very shortly by UEAC, it does not bode well for UEAC's ability to make the business judgments that it will certainly face in trying to finance the proposed leveraged buyout, and, if that transaction is completed, in running the airline,'' the release said.

Among other things, the non-contract workers are looking for improved pensions and assurance that the agreement with the unions would be binding and not subject to change by a new UAL managment.

The non-contract group includes reservations and ticket agents, professional and technical staffers, and management and supervisors excluding Chairman Stephen Wolf and other top officers.

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