The closing of the American Airlines overhaul base in north Kansas City is expected to have a significant impact in St. Joseph.

The company announced Wednesday that the base will close next September, eliminating 500 jobs.

Bill Caldwell, a long-time employee from southern Buchanan County, estimated that the overhaul facility, located near Kansas City International Airport, employs about 100 people from St. Joseph, southern Buchanan County or Platte County.

“There’s a lot of people at AA who live in St. Joseph and to the south,” he said. “The residual effect of losing 500 well-paying jobs in north Kansas City will hurt the St. Joe economy.”

The average wage at the overhaul base is $50,000 to $55,000 a year. About 450 workers are in the Transport Workers Union.

The moves will eliminate up to 700 jobs nationwide, about 5 percent of American’s maintenance work force.

Maintenance senior vice president Carmine J. Romano said in a letter to employees that the closures were “a difficult but important step” to reduce maintenance operations as American cuts back on flights due to the yearlong slump in travel.

American also has major maintenance bases in Tulsa, Okla., and Fort Worth, Texas.

The airline said Wednesday that by next September it will close maintenance stations at airports in Kansas City, Detroit, Minneapolis and San Jose, Calif., and shrink stations in St. Louis — where it is sharply cutting flights — and San Francisco.

American parent AMR Corp., based in Fort Worth, has lost $1.1 billion so far this year after losing $2.1 billion last year. Revenue is down 19 percent this year.

The Kansas City overhaul base employed more than 2,000 people 10 years ago, when it was still part of TWA.

Mr. Caldwell said one reason for the closing is that newer planes don’t require as much maintenance. “The newer planes have less corrosion. The engines are damned-near bulletproof,” he said.