The Federal Aviation Administration has asked Boeing for further analysis of the electrical grounding issues that last month caused a fresh halt to flights by 737 MAX jets, Reuters reported, citing two people familiar with the matter.
Last week the FAA outlined repairs needed to address the problem in three areas of the jet, saying it will cost about $155,000 to fix the 71 planes in operation in the U.S.
The new questions from the agency require Boeing to document that “numerous 737 MAX subsystems would not be affected by electrical grounding issues,” Reuters reported. That could delay the release of Boeing’s fix for the 100 or so jets worldwide that have been taken out of service because of the problem.
Asked directly about the report, Boeing responded with a statement that said, “We continue to work closely with the FAA and our customers to address the ground path issue in affected 737s.”
The manufacturing flaw discovered in early April arose from a small change in Boeing’s 737 MAX manufacturing process, The Seattle Times has previously reported. A backup electrical power control unit was secured to a rack on the flight deck with fasteners — in place of the rivets previously used.
This change was executed in such a way that it did not provide a complete electrical grounding path to the unit. The lack of secure electrical grounding could potentially cause malfunctions in a variety of electrical systems, such as the engine anti-ice system and the auxiliary power unit in the plane’s tail.
Fixing that defect in most of the affected planes was estimated to require about 24 hours per plane for the 68 U.S. aircraft on which multiple electrical panels require repairs, Bloomberg reported last week. On others, it could be quicker.