Boeing continues to investigate a fire that broke out Saturday night on the roof of a new 777X wing factory in Everett, Washington, leaving no one injured but company officials still unsure of the cause. A company spokesman told AIN Monday that the incident would not affect production schedules, which call for the start of final assembly in 2017 and service entry of the new widebody in 2020.

“That building is still under construction, so no one was inside,” said the spokesman. “There is no impact to the program schedule.”

Boeing expects to finish construction of the 1 million-square-foot composite wing center in May. It broke ground on the site in October 2014, seven weeks earlier than planned. The company has committed more than $1 billion for construction and outfitting of the new facility, located on the north side of the main final assembly building.