Boeing will move up to 2,300 workers off the 787 and 747-8 payroll in a second round of staff cuts as both aircraft become easier to build.
The workforce reductions, including an estimated 800 layoffs, come despite the company's effort to ramp up production on three product lines and deliver the 787-9 variant later this year.
Last month, Boeing acknowledged plans to layoff hundreds more contract workers at the 787 factory in Charleston, South Carolina.
In a note to members, however, the International Association of Machinists and Aerospace Workers (IAM) cautioned that the workforce reductions do not signal a change in Boeing's commercial outlook.
"This is not the start of a Boeing downcycle," the IAM says. "Production rates remain high and there is a seven-year backlog."
The job cuts instead reflect the fact that both programmes are winding down a massive change incorporation and refurbishment effort, which was required to modify dozens of aircraft already built in order to comply with design changes required for certification by the US Federal Aviation Administration.
Those efforts drove up the workforce dedicated to both programmes. An internal document dated last June, which was inadvertently posted to the company's internet site, showed nearly 8,000 employees assigned to the 787 programme alone, along with 2,816 for the 747-8 programme.