During a technical review last week of the proposed update to the MAX software, one of the monitors was not being initiated correctly. The stock closed down 2.3% in NY at $324.15, the day's biggest loser on the Dow Jones Industrial Average. Boeing lobbied for and helped craft the legislation, according to an October 2019 report in The New York Times.
The two recent crashes have resulted in all 737 MAX jets being grounded. The company had been hoping the plane would be back in service this spring, but the FAA has said it will not issue an approval until a series of milestones are met.
The aircraft maker says it is making the necessary changes and working with the Federal Aviation Administration.
'Our highest priority is ensuring the 737 MAX is safe and meets all regulatory requirements before it returns to service'.
The Boeing 737 factory is seen in Renton. While it has been tested on planes in flight, most of the software reviews have occurred in a special simulator used by engineers on the ground.
Flight control computers on the MAX were not communicating on startup as expected during an audit meeting with regulators last weekend, leaving it uncertain when the plane will fly. The company's long-term issuer default rating was downgraded by Fitch to A-minus from A.
This week, American Airlines Group Inc. and Southwest Airlines Co. both said they would extend cancellations of Max flights until early June. A week before his firing, the company chose to temporarily halt production of newer 737 MAX planes.
Boeing took a $5.6 billion (roughly Rs. 39,784.4 crores) charge in last year's second quarter and has disclosed billions more in higher production costs because of the Max.
They also said that the test was created to find such issues and to troubleshoot them.
The grounding has caused Boeing to halt production of the plane, prompted investigations by the Justice Department and Congress, led to lawsuits by the families of passengers in the two crashes, and caused the firing of former CEO Dennis Muilenburg.
Boeing was not able to tell ABC News if a fix will take days or weeks, but the company confirmed it will work on fixing the new software problem and other 737 Max related tasks simultaneously.
The FAA said there was nothing new in the emails and they would not affect the recertification process.