Boeing Max 737 jets could remain grounded into December because of friction between the manufacturer and international air safety authorities, The Wall Street Journal reported Monday.
Government and pilot union officials briefed on the matter told the outlet that the latest setback is tied to a briefing where regulators complained that Boeing failed to provide technical details and answer specific questions about modifications in the operation of Max flight control computers.
Boeing now reportedly has to resubmit briefing documents describing proposed software changes.
The changes, which have to be vetted by the U.S. Federal Aviation Administration (FAA), could significantly reduce the likelihood that many of the planes would be back flying passengers during the Christmas holidays.
Some industry officials in Europe are increasingly convinced the majority of the planes aren’t likely to resume carrying passengers until January at the earliest, according to the Journal.
The Max 737 has been grounded since early this year after two deadly crashes involving the model.
"Our best current estimate continues to be a return to service of the MAX that begins early in the fourth quarter," a Boeing spokesperson told The Hill.
"Our focus is on safety and ensuring the trust and confidence of customers, regulators and the flying public. Timing on return to service will be driven by the FAA and global regulators," the spokesperson added.
Updated at 11:43 a.m.