Debt-ridden plane-maker Boeing (NYSE:BA) has reportedly delivered layoff notices to more than 400 members of its professional aerospace labor union, as part of a larger workforce reduction plan amid ongoing financial challenges.

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 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,