White-collar staff for U.S. airplane maker Boeing Co. ratified a four-year contract with the company, putting labor issues mostly to rest for industry giant.

Engineers in the Society of Professional Engineering Employees in Aerospace voted 79 percent in favor of the contract, while technicians in the union voted 69 percent for ratification, the Seattle Post-Intelligencer reported Tuesday.

The contract includes an upgrade in retirement benefits and a pay raise that averages 20 percent over four years for the union's 21,000 members, the newspaper said.

The agreement also means the company will avoid a strike by engineers, which could have come on the heels of the International Association of Machinists and Aerospace Workers' strike that lasted 57 days and ended a month ago.

Ray Goforth, executive director of the engineers' union, said the just ratified contract includes "significant" improvements in wages and benefits. But, the contract needs to be time-tested to prove itself on the issue of giving engineers more control over company decisions to outsource work, he said.

"We won't know until we live with this contract for a while," he said.