The stock of Spirit AeroSystems, which supplies and makes parts for Boeing and Airbus, plunged after reporting a net loss in the fourth quarter due to costs related to its Dreamliner program and a reduced value of potential tax benefits.

Shares tumbled $6.46, or 19.6 percent, to $26.51 Thursday.

The company reported a net loss of $587 million, or $4.15 a share, compared with net income of $61 million, or 43 cents, a year earlier. Revenue at the Wichita, Kan.-based company was $1.49 billion, lower than analysts’ estimate of $1.55 billion.

The fourth quarter included a $381 million charge because of deferred tax assets and a net pretax charge of $546 million mainly related to its 787 program. Spirit makes components for all of Boeing’s current lineup of commercial jets, including the 787 Dreamliner.

“Although the magnitude of the program charges recorded during the quarter was stunning, we believe there is a definite plan to kill risk,” Howard Rubel, an analyst at Jefferies wrote in a note to clients. He rates the shares buy.

For 2014, Spirit said it expects revenue of $6.5 billion to $6.7 billion and earnings per share of $2.50 to $2.65.