Boeing has delivered layoff notices to more than 400 members of its professional aerospace labor union, part of thousands of cuts planned as the company struggles to recover from financial and regulatory trouble as well as an eight-week strike by its machinists' union.

Boeing started issuing layoff notices Wednesday to 17,000 employees to cut 10% of its workforce in an effort to shore up the aerospace giant's shaky finances.

Boeing said it will lay off about 220 workers at its SC factories, nearly all of them at sites that build engine components, cabin parts and the Dreamliner jet.