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737 MAX electrical faults to be finally rectified

written by Hannah Dowling | May 13, 2021

Boeing 737 MAX 8 in Ryanair Livery (Ryanair/Boeing)

Boeing and the US Federal Aviation Administration have finally settled on a fix for ongoing electrical faults located in multiple areas of the embattled Boeing 737 MAX.

The electrical faults resulted in nearly a quarter of all MAX jets being grounded around the globe, as the FAA continued to probe Boeing on the extent of the issue before giving the planemaker the green light to complete repairs and return planes to the sky.

Boeing has said it has already issued two bulletins to airlines and operators of the 106 affected MAX aircraft that contain instructions on how to rectify the electrical problems.

“After gaining final approvals from the FAA, we have issued service bulletins for the affected fleet,” Boeing told the media.

“We are also completing the work as we prepare to resume deliveries.”

According to FAA administrator Steve Dickson, the agreed-upon repair is a “pretty straightforward fix”.

The news will come as a welcome relief to airlines forced to keep their MAX fleets grounded, who were expecting information on a solution to the electrical issues at least a week ago.


Electrical flaws were initially found in a number of MAX cockpits’ backup power control systems in mid-April.

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 issue was labelled by Boeing as being caused by a “production issue”, and was limited to jets delivered in the months after the FAA lifted its grounding ban on the MAX.

However, the FAA later 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.

Now nearly a quarter of all delivered MAX jets are affected by an FAA airworthiness directive keeping them on the ground until Boeing finds a way to rectify the issue.

Boeing also announced in April that it would halt all deliveries of the MAX until the issue was fixed, just five months after re-starting deliveries after the jet’s 20-month long recertification battle.

Last week, World of Aviation reported that Boeing had approached the FAA with its proposed repair for the multiple electrical faults, however, the process was put on ice as the FAA probed Boeing for more evidence to prove that the electrical faults don’t extend into other parts of the aircraft.

While the FAA initially approved the service bulletins provided by the planemaker, after discussions with Boeing, the regulator asked for additional information and analysis on whether or not any other subsystems throughout the jet could be affected by similar grounding issues.

In its service bulletin, Boeing has proposed adding a bonding strap or cable that workers screw onto two different surfaces creating a grounding path, for the affected electrical circuit, two of the sources said.

Sources also specified that the electrical grounding problems that have been located to date came as a result of Boeing changing a manufacturing method, as it worked to increase the speed at which it can produce the jet.

They said that the change made, which sparked the issues, pertained to a hole-drilling process.

Boeing initially told airlines that rectifying the issue could take as little as a few hours, or up to a few days, per jet.

737 MAX electrical faults to be finally rectified Comment

  • Mac Carter


    I find it inconceivable that basic electrical grounding issues would be able to pass quality control systems at Boeing. Sufficient electrical grounding capacity should, by design, be incorporated in existing electrical looms.
    Very basic omission on Boeings part.
    I believe it is totally unacceptable that service personnel to have drill instrument panels to facilitate installation of proprietary grounding straps, on assets which Boeing’s customers have invested in the vicinity of one hundred and fifty million dollars, to render said assets safe and fit for purpose.

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