More than 3,200 members of the International Association of Machinists and Aerospace Workers District 837 walked off the job at midnight on 4 August after rejecting Boeing Co.’s latest labour proposal, triggering the first strike at the company’s St. Louis-area defence facilities since 1996. The work stoppage affects plants in St. Louis and St. Charles, Missouri, and Mascoutah, Illinois, where employees assemble F-15 and F/A-18 fighter jets, the T-7 trainer aircraft and the MQ-25 refuelling drone. The four-year contract that was voted down offered a 20% general wage increase, lifting average pay by roughly 40%, alongside a US$5,000 signing bonus, additional vacation and sick leave, and changes to work schedules. Boeing Air Dominance Vice-President Dan Gillian said the company was "disappointed" by the outcome but had activated a contingency plan using non-striking staff. Union leader Tom Boelling countered that members deserve an agreement reflecting their skills and the importance of the programmes they support. Boeing’s defence division generates almost a third of the company’s revenue, and the strike comes as the unit ramps up output for several Pentagon contracts. While Chief Executive Kelly Ortberg told analysts last week that the company could manage the disruption, Boeing shares slipped about 1.1% in early New York trading. The walkout follows last year’s seven-week stoppage by 33,000 machinists at the firm’s commercial-jet plants in Washington state.