(Bloomberg) -- Spirit Aerosystems Holdings Inc. Chief Executive Officer Tom Gentile abruptly resigned with immediate effect, leaving Boeing Co.’s key supplier to search for a permanent successor just as the manufacturer works through a series of damaging production defects. 

Patrick Shanahan, a member of the embattled company’s board of directors, was named interim CEO, Spirit said in a stock exchange filing. Gentile will serve as a consultant for three months to ease the transition, it added 

Spirit, which is a supplier to Boeing and Airbus SE, has come under fire for multiple manufacturing defects on Boeing’s workhorse 737 jet, for which it builds most of the fuselage. The company also faces mounting losses on the components it builds for Boeing’s 787 Dreamliner and Airbus’s A350 and A220 aircraft. 

“The path forward is focused on executing on rate ramps, dealing with forward loss contracts, and cleaning up the balance sheet,” said Sheila Kahyaoglu, an aerospace analyst at Jefferies.

In August, Boeing disclosed that some holes in the 737’s bulkheads that help maintain cabin pressure were improperly drilled by Spirit, requiring inspection by X-ray and slowing output of the planemaker’s most important aircraft. The latest issue followed a separate quality lapse at Spirit involving brackets in vertical tail fins.

Gentile came under fire from investors after Spirit said cash flow won’t fully recover next year as it grapples with higher wages tied to a new contract following a strike and the effect of inflation on some of its money-losing contracts.

Shanahan spent more than 30 years at Boeing before moving into politics, becoming Deputy Secretary of Defense in 2017. Former President Donald Trump nominated him as Defense Secretary after James Mattis quit in December 2018, though Shanahan later withdrew from consideration.

(Updates with analyst comment in fourth paragraph.)

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