The Boeing 737 Max continues the stranding and causes thousands of new flight delays

The airlines predict that Boeing's 737 Max commercial jetliners will remain out of action late this fall, as the company is working to resolve many of the technical issues that have landed the aircraft since early March.

The three US airlines that operate Max – American Airlines, United and Southwest jets have recently announced the cancellation of 737 Max flights on November 2, November 3, and October 1, respectively, affecting hundreds of flights each year. day. The new cancellation dates reflect a major revision of the anticipated summer schedule presented as a conservative estimate.

Airlines are waiting for the Federal Aviation Administration to approve a software patch designed by Boeing for a flight control system that played a role in two fatal accidents. According to an FAA directive issued in early March, this fix was originally scheduled to be delivered by April, but the process was complicated by the discovery of other technical issues.

A Boeing official, speaking on condition of anonymity because the person was not allowed to publicly discuss the problem, said that the company is waiting to submit all Software updates required at the end of September approval. This could pave the way for the return of jet planes in November, said a Boeing official. American Airlines executives say the company remains confident that the aircraft will be recertified to fly before the end of the year.

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However, this schedule assumes that the controllers do not encounter additional problems with the jet or associated hotfixes. The FAA has refused to come up with a firm timetable, or even an estimate, for when it intends to lift its grounding order for the Max.

"The FAA is following a meticulous process, not a prescribed timetable, to bring the Boeing 737 Max back to passenger service," FAA spokeswoman Lynn Lunsford said Sunday. "The FAA will lift the ban from the aircraft when we deem it safe to do so."

The 737 Max is the latest version of a trusted Boeing jetliner. It was an even more fuel-efficient version of Boeing's best-selling aircraft, an improvement made possible by the changes made to the aircraft's engines.

The new design was likely to tip the nose of the aircraft and cause a stall. Boeing has therefore added a new flight control system called the Maneuverability Enhancement System (MCAS) which can, in some rare but dangerous situations, override pilot commands and automatically switch the nose of the aircraft down. .

The pilots who piloted these aircraft had only been informed of this change a few weeks after the fatal crash of 189 people in Indonesia last October. Then, in early March, another Boeing Max plane fell to Ethiopia in similar circumstances, killing 157 people.

Regulators around the world immobilized the plane shortly after the second crash, and Boeing and the FAA announced that they were working on a hotfix package designed to take into account MCAS. This update is complete, according to a Boeing official, who spoke on condition of anonymity because he was not allowed to discuss the problem in public.

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In early April, Boeing then revealed to the Washington Post that he had discovered another software problem related to the flaps of the aircraft and other flight control equipment. And in June, the FAA discovered an entirely new security problem with the 737 Max, forcing the company to perform another software repair.

The grounding has had a heavy financial impact on US airlines and their customers. Flight cancellations are expected to affect approximately 115 flights per day at American Airlines; 150 flights a day to the southwest; and about 5,000 total flights to United during the planned grounding.

Fenit Nirappil contributed to this report.