“Boeing has recommended to 16 customers that they address a potential electrical issue in a specific group of 737 Max airplanes prior to further operations,” the company said.
Airlines need to verify that one of the components of the plane’s electrical system is sufficiently grounded, Boeing stated. The company said it is working with the US Federal Aviation Administration to address the problem.
Main power system
CNN safety analyst David Soucie said he believes the issue specifically involves a backup to the main power system that powers all of the aircraft’s electrical parts. The system is roughly analogous to the circuit breaker panel in a house.
The fact that the planes were grounded indicates that this was is potentially a “catastrophic” problem that could have caused a fire, Soucie said. But he noted it’s a good sign for the plane — and its safety — that the potential threat was discovered before there was an incident.
Southwest, which owns the most 737 Max planes, said Friday that the issue affects 30 of those 58 jets in its fleet. It says those planes will be replaced by other aircraft and that it “anticipates minimal disruption to our operation” since it flies Maxes on a limited schedule and the planes account for only a fraction of its planes in service.
United said the problem affects 16 of its 30 Max planes.
“We are working to swap out aircraft to minimize the impact to our customers,” it said. “We are in communication with Boeing to understand the timeline for returning the aircraft safely to our fleet. We do not have an estimate right now.”
American said the issue does not affect the 24 737 Max jets it had in its fleet before the original grounding, only in the 17 jets that were built during or after the grounding and delivered to the airline since November.
“We will continue to work with the FAA, Boeing and our union leaders and their safety teams as a thorough assessment of the issue is completed,” said American.