Boeing warned on Thursday that it expected a fourth-quarter loss of about $4 billion to close a year marred by a production quality crisis, stricter regulatory scrutiny, supply chain delays and a crippling strike by U.

KEY TAKEAWAYS Boeing shares are falling in premarket trading after the plane maker projected a much wider-than-expected fourth-quarter loss.The plane maker attributed the large loss to the nearly two-month strike that crippled production as well as charges around its defense segment and staff cuts.