FAA-ordered audit reveals issues with tail control wiring on grounded jet

Boeing has revealed a new potential design flaw with the grounded 737 Max which could lead the aircraft to crash if pilots do not take evasive action, according to the New York Times.

Boeing conducted an internal audit in December at the request of the US Federal Aviation Administration (FAA) to determine whether an assessment of the dangers of key systems had been undertaken accurately. The newspaper reported that the audit was requested following new assumptions about how long it might take pilots to respond to emergencies and cited sources including a senior engineer,

The report added that new, previously unreported, issues had been discovered, included concerns with the wiring which controls the tail of the Max. Boeing is now investigating whether two bundles of critical wiring are too close together which could cause a short circuit.

Boeing investigating ‘short circuit’ theory

The New York Times added that Boeing is still trying to ascertain whether the short circuit could occur on a flight and whether it would need to separate the wire bundles in approximately 800 Max jets which have already been built.

The manufacturer said that the fix would be relatively simple and would take one to two hours per plane to separate the wiring bundles using a clamp. The engineer told reporters that finding and resolving issues was not unusual or particular to the Max or Boeing.

Boeing informed the FAA about the potential vulnerability last month, and the company’s new chief executive discussed potential wiring changes in an internal conference call last week, according to the newspaper.

Meeting safety and regulatory requirements ‘top priority’

A statement by Boeing said the company said that ensuring the 737 MAX met all safety and regulatory requirements before its return to service was the company’s “highest priority.”

It added: “We are working closely with the FAA and other regulators on a robust and thorough certification process to ensure a safe and compliant design. We identified this issue as part of that rigorous process, and we are working with the FAA to perform the appropriate analysis. It would be premature to speculate as to whether this analysis will lead to any design changes.”

Regulators have so far focused on the plane’s Manoeuvring Characteristics Augmentation System (MCAS) software which was identified as a factor in both the fatal crashes of Ethiopian Airlines Flight 302 in March 2019 and Lion Air Flight 610 in October 2018. The entire MAX flight has been grounded since March 2019 and Boeing is hoping to return the aircraft to service in spring 2020.

New CEO takes position on January 13

Last month Boeing announced that its Chief Executive Dennis Muilenburg, following criticism of his handling of the crisis by families of the Ethiopian Airlines and Lion Air crash victims. He will be replaced by board chair David Calhoun on January 13 with Chief Financial Officer Greg Smith currently serving as interim chief executive before Calhoun comes on board.

Boeing said the leadership change “was necessary to restore confidence in the Company moving forward as it works to repair relationships with regulators, customers, and all other stakeholders”.

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