HARTFORD - (AP) - Sikorsky Aircraft Corp. announced onThursday that it is trimming its worldwide workforce of 18,000 byabout 540 jobs to remain competitive in the helicopter design,manufacturing and service industry.

Paul Jackson, the company's director of communications, calledthe move to cut about 3 percent of the workforce "a difficultdecision." The company is not disclosing a breakdown of where thejob cuts will be.

Sikorsky is headquartered in Stratford and has about 9,000employees in Connecticut.

Jackson said the company does not yet know how many layoffs willbe necessary until it is clear how many of the eligible unionizedworkers in Connecticut accept a voluntary separation package.

He said Sikorsky, whose parent company is the Hartford-basedUnited Technologies Corp., has experienced strong growth whileother manufacturers have had to downsize, move or close. Still, hesaid, the company needs to reduce its workforce as it goes forward.

"Our sales have increased nearly 40 percent since 2007, andwe've been able to expand our workforce by nearly 59 percent sincethen. But those rates aren't sustainable," Jackson said. "We areentering a new world, with moderating growth in line with U.S. andinternational economies and their impact on our commercial andmilitary customers."

All five branches of the U.S. armed forces use Sikorskyhelicopters, as well as military and commercial operators in 40nations, the company's website says.

In the U.S., Sikorsky has manufacturing and assembly plants inStratford, Troy, Ala., and West Palm Beach, Fla. The company alsohas engineering and design centers in Alabama, Kentucky, Montanaand Texas. In addition, Sikorsky has manufacturing and assemblyfacilities in Mielec, Poland, as well as joint venture manufacturing operations in Turkey and China. Sikorsky has a presence in other states and countries as well.