Boeing Co. has resumed deliveries of its 737 MAX series aircraft, following a one-month pause implemented when an electrical-grounding issue was discovered to be affecting some jets’ cockpit back-up power control unit, the units' storage racks, and cockpit instrument panels. The electrical problems were determined to be rooted in production changes implemented after the previous, 19-month grounding that concerned the 737 MAX flight-control software.
The two issues were not related.
Earlier this week Boeing released two maintenance bulletins concerning the electrical defects to the operators of 109 737 MAX aircraft discovered to have the electrical grounding problem. The FAA authorized the electrical updates, and it noted that the jets would require a simple repair before returning to service.
Most of the affected airlines are operated by U.S. carriers Southwest Airlines, American Airlines, and United Airlines. After the FAA authorized the electrical repairs, each of these carriers indicated the grounded aircraft would return to service shortly.