The FAA issued a final airworthiness directive covering a small portion of the 737 MAX 8 and MAX 9 fleets yesterday. In the United States, only 79 aircraft are impacted. The directive mandates the installation of two bonding jumpers on the affected aircraft as an electrical fault could cause a failure of the standby power control unit. In certain situations, a loss of ground through that unit and the P6 panel could result in a significant loss of flight crew instrumentation and displays, posing a safety of flight risk. This is the final issuance of a draft AD circulated in February
The fix is relatively inexpensive—$255 in labor and $180 in parts—and can be accomplished quickly. Repairs are mandated for the affected aircraft before May 22nd.
Comments from a Boeing whistleblower, Ed Pierson, and his Foundation for Aviation Safety called for the grounding of the 737 MAX fleet over this issue. Still, the FAA indicated that the AD isolated and fully addressed the problem. Boeing had also commented that it wanted to change the background section of the AD, but the FAA stood by the draft version in the finalization process.  The AD effective date is May 22, 2024.
