ST. MARY -- Sabreliner Corp. is expanding in Southeast Missouri.

The diversified aviation service, maintenance and modification company headquartered in St. Louis, plans to open a new sheet-metal fabrication plant at St. Mary Monday.

The plant will be in an existing 5,225-square-foot building in St. Mary Industrial Park, which is about 12 miles from the Perryville Municipal Airport. Sabreliner has a plant at the Perryville airport. It is one of 13 the company already operates.

The St. Mary plant is needed to enable Sabreliner to manufacture parts it could not make at Perryville due to space limitations, said Ron Herman, manager of the Perryville operation.

Parts longer than 14 feet can be fabricated for aircraft manufacturers such as Gulfstream, Airbus, Lockheed, Boeing and others at the St. Mary facility, he said.

Sabreliner currently is manufacturing smaller parts for Boeing in its Perryville plant.

"St. Mary Industrial Park -- about a mile south of St. Mary on Route 61 -- is ideal because it is close to our Perryville airport plant and a drop-off point for deliveries between here and St. Louis facilities," said Herman.

Equipment planned for the St. Mary facility include production routers, power brakes, stretch presses and roll form equipment. Much of the equipment already has been moved to St. Mary, where activity will start Monday.

Ten of the Perryville workers will be transferred to the St. Mary operation. Those numbers are expected to increase to as many as 20, depending on the work flow.

Sabreliner, with annualized sales of more than $250 million, employs more than 2,000 people at its plants in seven states. It services government, military, corporate, airlines and cargo aircraft, engines, systems and components.

The company employs 213 at Perryville.

Sabreliner recently announced that it had reached an agreement to sell the Navy 17 of the T-39N aircraft and simulators equipped for radar training at price of $42.5 million. Under the agreement, Sabreliner will continue to provide aircraft maintenance and pilot contract services through the contract period, which ends Sept. 30, 1998. At that time the maintenance contracts will be rebid, and Sabreliner will be among bidders.