Return to service of Boeing 737MAX could further delay as Boeing found that wires on 737MAX were bundled improperly and may trigger the similar scenarios that lead to two fatal crashes.
Placement of wire bundles were too close together and does not meet the FAA regulations for safe wire separation.
Boeing engineers didn’t notice this issue during the design and manufacturing stages of the 737MAX, and FAA also failed to detect it during the original design and certification of Boeing 737 MAX.
The wiring issues have been found in more than a dozen locations on the 737 Max, in which the wire bundles may be placed too close together.
After assessing the issue for weeks, Boeing has submitted its initial recommendation to solve the issue to the FAA, and argues that wiring layout on 737MAX is similar to that on 737NG.
It says that Boeing 737MAX has recorded 205m flight hours with this wiring layout and had recorded only 16 failures in service, but non of them are related to wiring layout.
According to FAA regulations, the earlier 737 NG model was certified long before the current wiring-separation standards because they came into force long after that jet was certified.
Pulling out and rerouting wires on the almost 800 MAXs already built can create unintended hazards, costly, time-consuming, and may delay 737MAX returning to service.
According to FAA technical staff the wiring on 737MAX does not comply with regulations and requires fixing before allowing it to return to service.
FAA issued an official statement on Friday hinting that Boeing may be forced to comply with the wiring regulation.
“We will rigorously evaluate Boeing’s proposal to address a recently discovered wiring issue with the 737 MAX,” the FAA said. “The manufacturer must demonstrate compliance with all certification standards.”
To date, the 737MAX crisis has cost Boeing $9 billion, and affected suppliers and airlines.