Boeing Machinists who help build fighter jets in St. Louis and two other locations voted by a 3-to-1 margin Sunday to a new labor deal with a contract extension.

The new contract will expire in July 2022 for more than 2,300 members represented by the International Association of Machinists and Aerospace Workers District 837, according to a Boeing statement. It was set to expire in January 2015.

Within 30 days, eligible members will receive an $8,000 signing bonus. They will also receive general wage increases every two years starting in 2016 through 2022, with lump-sum payments in 2017, 2019 and 2021.

IAM members will also transition retirement benefits to a 401(k) defined savings plan in 2016. They will keep the accrued value of their traditional pension plan. The contract also offers buyouts for veteran workers, a move meant to avoid layoffs.

Boeing said the new contract will better position the company to compete for work and avoid layoffs.

Boeing workers in the St. Louis area build the F/A-18 and F-15 fighter planes as well as the EA-18G electronic attack aircraft, along with weapons and support programs.

The new contract covers Boeing union workers in St. Louis; China Lake, Calif.; and the Naval Air Station in Patuxent River, Md.

Reach Warren L. Wise at 937-5524 or twitter.com/warrenlancewise.