Boeing (BA -0.76%) on Wednesday said it lost almost $12 billion in 2020 and further delayed the debut of its 777X jet, a fresh reminder that the issues that plagued the company last year will not be resolved easily.

The aerospace giant recorded a net loss of $11.94 billion on revenue of $58 billion for the year, with total sales dropping 24%. The global pandemic sapped demand for air travel and devastated airlines, reducing demand for new planes.

A Boeing 737 jet in flight.

Image source: Boeing.

Boeing also spent most of the year dealing with the grounding of its 737 MAX, which was only cleared to returned to service late in 2020 after nearly 20 months out of service.

"2020 was a year of profound societal and global disruption which significantly constrained our industry," CEO Dave Calhoun said in a statement. "The deep impact of the pandemic on commercial air travel, coupled with the 737 MAX grounding, challenged our results."

In response to the pandemic, the company has cut production across its commercial jet lineup, and on Wednesday it said it expects the 777X, an updated version of one of its largest planes, to enter service by late 2023. Boeing had originally hoped to introduce the 777X in 2020, but the plane's most important customer had hinted earlier this month that it was concerned the debut would slip past a revised 2022 target.

Boeing booked a $6.5 billion pre-tax charge related to the 777X delay, continuing a difficult run of new plane development. The investigation into a pair of fatal 737 MAX crashes revealed troubling details concerning the company's production and certification work, and that has increased the regulatory scrutiny on the 777X.

Boeing bled through $4.3 billion in the fourth quarter, bringing its total free cash flow for the year to a negative $19.7 billion. The company ended the quarter with $25.6 billion in total cash and marketable securities.