RENTON, WA—Boeing Co. is facing a problem as it races to meet demand for single-aisle, fuel-efficient jets: Where to store unfinished 737s piling up at its factory near Seattle.

AUBURN, WA—Production of fuselage stringers for the first Boeing 737 MAX has begun at the company’s assembly plant here.

RENTON, WA—Boeing will build a third assembly line for its 737 MAX jet family alongside one of the two existing lines at its assembly plant here. The company will hire hundreds of works within the next five years.

RENTON, WA—Boeing is grappling with how to pack a third assembly line into its assembly plant here, which needs to build 737s at a record pace.

WICHITA, KS—Spirit Aerosystems is preparing to produce up to 60 fuselages a month to keep up with demand from Boeing’s 737 assembly plant in Renton, WA.