Boeing Co. and its machinists union have reached a tentative contract agreement, which, if approved, would end a three-week strike that shut down the company's airplane production.

Mark Blondin, a union district president, confirmed the agreement Sunday and said union members would vote on the deal Thursday.

"I'm just proud of our membership," Blondin said. "They stood solid, unified, and that solidarity is what finally got the company to do the right thing."

Boeing spokesman Charles Bickers said the company believes the agreement is reasonable and reflects compromise on both sides.

"The total cost to Boeing is similar to the previous contract offer and meets our definition of a reasonable settlement," said Alan R. Mulally, head of Boeing's commercial airplanes division.

Blondin said the deal calls for Boeing to make no changes to its health care plan, a major change from the premium and other increases Boeing had demanded.

Pension payouts for union members would increase, and Boeing agreed to continue offering medical benefits for retirees, Blondin said. There would be no general wage increase, but workers would receive an 8 percent signing bonus, plus $3,000 payouts in the second and third years of the contract, he said.

Dropped from the original offer was an incentive pay program that would have provided bonuses if the company met or exceeded financial targets. Also, the offer terms are the same for workers in the Puget Sound area; Gresham, Ore.; and Wichita, Kan. Previously some terms were less for Wichita workers.

About 18,400 machinists who assemble Boeing's commercial airplanes and some key components walked off the job on Sept. 2, forcing the Chicago-based company to immediately stop its airplane production.