SEATTLE, Washington: Boeing engineers and technical workers have overwhelmingly rejected the U.S. planemaker's proposed four-year labor contract and authorized their negotiating team to call a strike when the current agreement expires on October 6, union officials said.

The 17,000 members of the Society of Professional Engineering Employees in Aerospace, or SPEEA, voted separately on the tentative agreement. Engineers rejected it by 64 percent, while about 72 percent of technical workers voted against it, the union said.

No new negotiations are currently scheduled between Boeing and SPEEA, the company's largest white-collar union.

"We're disappointed our engineers and technical workforce voted no on our offer. As a result, we are now implementing our strike contingency plan and diverting the dollars we had wanted to invest in our SPEEA-represented team to prepare for a potential strike," Boeing's Ben Nimmergut, vice president and functional chief engineer for production engineering, said in a statement.

"We have no choice but to implement our contingency plan. We have a responsibility to the rest of our workforce and our customers to build on our progress over the last two years and maintain our momentum," he said.

A work stoppage by SPEEA members would further delay Boeing's certification campaigns for its 737 Max 10 and 777-9 aircraft, both of which are already several years behind schedule.

A union spokesperson said the negotiating team plans to survey members to determine what it would take to secure approval for a four-year contract.

SPEEA negotiating team member Kevin Boyd said the strike authorization vote "gives a lot of transparency."

"The membership has a strong need here, and they're willing to do what it takes to get it," Boyd said.

Katheryn Durkee, another member of the negotiating team, said SPEEA members "really want to have careers and not jobs at Boeing."

Several union members who voted against the agreement said the proposed wage increases were insufficient to keep pace with Seattle's high cost of living and were lower than what competing companies have paid employees.

The offer included wage increases tied to inflation, capped at 3 percent, as well as individual performance and other unspecified metrics determined by Boeing.

Several SPEEA members said the 3 percent cap on inflation-based raises would nearly guarantee that their salaries fall behind inflation. The Consumer Price Index for the Seattle area, where most SPEEA members work, rose 4.5 percent over the past year, according to July data from the U.S. Bureau of Labor Statistics.

Boeing said its proposal would have provided SPEEA members with their largest wage increase in 40 years.

SPEEA has not negotiated a new contract with Boeing for its Northwest members since 2012. Members approved contract extensions in 2016 and 2020.

SPEEA members last went on strike for 40 days in 2000. In 2024, Boeing commercial aircraft production in the Seattle area halted when about 33,000 members of the International Association of Machinists and Aerospace Workers went on strike for seven weeks.