DES MOINES (AP) - A walkout by Mesaba Airlines mechanics, who currently are holding a strike authorization vote, could leave some northern Iowans grounded.

Strike ballots mailed to union mechanics at Mesaba will be counted March 15, according to the Aircraft Mechanics Fraternal Association.

In Iowa, Mesaba operates numerous flights for Northwest Airlink, a commuter airline that feeds Northwest Airlines in Minneapolis.

The Waterloo Regional Airport depends on Mesaba for four or five of its six daily Northwest flights, depending on the time of year.

"We have eight commercial service airports in the state and two of them, Fort Dodge and Mason City, are served exclusively by Mesaba," said Tim McClung, marketing manager for the Iowa Aviation Office.

Mesaba also serves airports in Cedar Rapids, Sioux City and Des Moines, where the airline operates a maintenance center.

"We did have a pilot strike last year and so we do know that Fort Dodge, Mason City and Sioux City would be significantly affected," McClung said.

Mesaba signed a contract with its pilots in January 2004 after a strike deadline passed and hundreds of flights were canceled.

"We canceled a day and a half of flights while the two sides negotiated," Mesaba spokesman Dave Jackson said.

In a statement, Jackson said Mesaba expects the national mediation board to schedule negotiations when it feels both sides can make progress.

"We look forward to reaching a fair contract that recognizes the company's economic circumstances," he said. "Our focus in the meantime is a safe, efficient operation."

The mechanics would be unable to strike until the mediation board releases them from negotiations and a 30-day cooling-off period passes.

A telephone message left Wednesday for the union was not immediately returned.