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 on Wednesday it is issuing layoff notices starting this week to workers impacted by a broader plan by the heavily indebted planemaker to cut 17,000 jobs, or 10% of its global workforce. U.

One week after Spirit AeroSystems announced it has "substantial doubt" about its ability to continue as a going concern, Boeing is offering help.

In April, Boeing provided a $425 million advance to support Spirit's liquidity. Spirit, Wichita's largest employer with around 12,800 full-time workers, previously disclosed it has spent all of that money, as well as the entirety of a $350 million bridge loan that was set up earlier this year.

Spirit AeroSystems said on Tuesday that Boeing will pay a total of up to $350 million in advance payments to the firm, providing the struggling supplier a lifeline as it continues to burn cash after four consecutive years of losses.