Spirit AeroSystems said on Monday its quarterly losses more than doubled as 737 fuselage shipments to its biggest customer Boeing fell and losses mounted on its Airbus A220 program.

Net loss for the second quarter widened to $415 million from a loss of $206 million, an indication of Spirit’s fragile finances and the importance of Boeing’s deal to buy back the supplier it spun off in 2005.

Spirit said its results were hit by delivery delays on Boeing’s strong-selling 737 MAX jet, which saw slower production following a mid-air panel blowout in January. Shares of the supplier were down 2.2% after the bell.

Spirit delivered 27 737 fuselages in the quarter through June 27, lower than it anticipated and sharply down from the 74 it delivered in the year-ago period.

The company has struggled to stem losses and stabilize cash flows following troubles at Boeing. Its ability to deliver clean 737 fuselages without quality problems will be key for Boeing, which expects to produce the jets at a rate of 38 a month by year-end.

The U.S. supplier has also lost money on Airbus’ A220 program on higher costs. During the second quarter, Spirit recorded $25 million of forward losses on the program. Overall, it recorded net forward losses of $214 million in the period.

The company said it has developed plans to pursue various options to improve liquidity, as it burnt $597 million in cash. Analysts on average expected a cash burn of $169 million, according to LSEG data.

Spirit said it borrowed $200 million under a bridge term loan facility last month.

Adjusted loss per share was $2.73, wider than expectations of 90 cents. Quarterly revenue of $1.49 billion missed analysts’ estimate of $1.59 billion.