The US Federal Aviation Administration and Boeing have confirmed that 106 Boeing 737 MAX aircraft have been grounded around the world as the planemaker continues to investigate a way to fix the jets’ numerous electrical faults.
Earlier notices to operators of the affected jets suggested that operators could themselves organise engineers to repair the aircraft in a task that Boeing stated could be completed in mere hours.
However, the US regulator and Boeing have now said that all 106 aircraft potentially affected by this electrical fault are to remain grounded while Boeing attempts to find a way to rectify the problem.
The electrical issue involves a lapse in the grounding capabilities of some electrical circuits located in the cockpit. Grounding capabilities are vital in order to maintain a user’s safety in the event of a surge of voltage that could otherwise result in a shock or electrocution.
The fault was initially thought to be contained to the cockpit’s backup power control system. However, the FAA stated that “subsequent analysis and testing showed the issue could involve additional systems”, including the standby power control unit, a circuit breaker panel and main instrument panel.
The issues were originally thought to only affect 90 of the 450 737 MAX aircraft that have been delivered to date. However, the FAA and Boeing have now said the total number of affected jets is 106.
In a formal notice to global aviation regulators, the FAA stated that 106 MAX jets, 71 of which are US-registered, are to “remain on the ground while Boeing continues to develop a proposed fix” for the issues.
The notice also stated that the FAA will soon issue an airworthiness directive “mandating corrective action before further flight for all affected airplanes”.
The three major airlines in the US – American Airlines, United Airlines and Southwest Airlines – together have had to remove more than 60 jets from service.
These US carriers appear confident that Boeing will rectify the issue within the coming days and weeks, with American Airlines president Robert Isom stating the airline already has a “pretty good idea of exactly what the issue is and the remedies that need to be attended to”.
Other operators impacted by the grounding include Cayman Airways, Copa Airlines, GOL Linhas Aereas, Iceland Air, Minsheng Leasing, Neos Air, Shanding Airlines, SilkAir, Spice Jet, Sunwing Airlines, TUI, Turkish Airlines, Valla Jets Limited, WestJet Airlines and Xiamen Airlines.
The FAA said it has “verified all operators with affected airplanes have voluntarily taken those aircraft out of service”.
The faults have no connection to the MCAS operating system that was linked to the two fatal 737 MAX crashes in 2018 and 2019, which sparked the near two-year grounding.
It is not yet clear whether future 737 MAX deliveries will be affected, or whether they too require checks for electrical faults.