Boeing's 737 safety mess just got worse

• The National Transportation Safety Board has more concerns about Boeing's planes.
• It said at least 40 airlines outside the US may be operating aircraft with risky rudder parts.
• This is the latest blow to Boeing, which has been plagued by safety probes.

The National Transportation Safety Board (NTSB) has flagged fresh concerns with Boeing's 737 planes, saying that at least 40 airlines outside the US may be operating aircraft with faulty components.

The NTSB issued a press release on Thursday, saying it had issued urgent safety recommendations to Boeing and the Federal Aviation Administration (FAA).

The release said that the NTSB was investigating a February 6 incident with a United Airlines Boeing 737 Max 8 plane, which experienced "stuck" rudder pedals while landing at Newark Liberty International Airport in New Jersey.

The Board said that its investigators tested a rollout guidance actuator — one of the rudder control components from the affected airplane — at the component's manufacturer, Collins Aerospace.

When tested with another identical unit from a separate airplane, both actuators failed. Moisture was detected in both units.

Collins Aerospace later found that the sealed bearings on the units had been incorrectly assembled, "leaving the unsealed side more susceptible to moisture that can freeze and limit rudder system movement," per the release.

The NTSB said that Boeing's 737 flight manual instructs pilots facing a jammed rudder to overpower the system by applying "maximum force." But the Board warned that such force on faulty rudders could
"unintentionally cause loss of control or departure from a runway."

NTSB Chair Jennifer Homendy wrote a September 30 letter to the FAA's administrator, Michael Whitaker, saying she was concerned that the FAA "did not take this issue more seriously until we issued our urgent safety recommendation report."

She added that she had been made aware the "FAA has been downplaying the urgency of this issue, maintaining that the units are no longer in service."

Homendy said that Boeing had said that it had received 353 affected actuator units since February 2017.

Per Homendy's letter, 271 affected actuators may now be installed on aircraft in service operated by at least 40 foreign air carriers. She added that 16 units "may still be installed on US-registered aircraft."

Homendy also slammed Boeing for failing to inform United Airlines that faulty actuators were installed in the 737 planes it had delivered to them.

"We are concerned of the possibility that other airlines are unaware of the presence of these actuators on their 737 airplanes," Homendy wrote.

"Not making operators fully aware of the installed systems and equipment on the airplanes delivered to them is unacceptable and cannot continue to be tolerated," she added.

A bad look for Boeing

Guy Gratton, an associate professor of aviation and the environment at Cranfield University, told BI that component faults reflect poorly on Boeing.

"It's another instance of national authorities in the USA (the Federation Aviation Administration, and the National Transportation Safety Board) stepping in to address safety issues that Boeing themselves should have already identified and rectified," Gratton said. "I'd anticipate their customers worldwide being disappointed in that."

However, he added that he thought this issue was not as serious as Boeing's past safety issues, like the January 5 incident when the door plug on an Alaska Airlines passenger plane — a 737 Max 9 model — detached during a flight, forcing pilots to make an emergency landing.

"This fault could not in itself lead to loss of an aircraft, and even an aeroplane going off the side of a runway, whilst extremely embarrassing and expensive, would be unlikely to lead to loss of life," Gratton said.

He added: "I'd still be content to get into a Boeing 737, and I do — but it does continue to show the company as being troubled, and its products less trustworthy than those of the obvious competitors."

Latest blow to an already beleaguered Boeing

Boeing shares dropped 2.74% on Monday.

It's also worth noting that the NTSB probe is the latest setback for the company. Their Max family has been plagued by safety concerns since the two crashes of its 737 Max jetliners in 2018 and 2019 that killed a total of 346 people.

And following the Alaska Airlines door plug incident, the FAA barred Boeing from expanding production on Max plane models until quality and safety issues were addressed.

A string of whistleblowers have also alleged this year that the company is lax with safety and quality control. Some bombshell allegations were publicized in a sprawling 204-page report released on June 17 by the Senate subcommittee that investigated Boeing's safety and quality practices.

These accounts include testimony from Sam Mohawk, a quality assurance inspector for Boeing, who alleged that the company lost track of hundreds of faulty 737 parts and ordered staff to conceal improperly stored plane parts so FAA inspectors would not see them.

Merle Meyers, a former Boeing quality manager, said that Boeing's manufacturing team regularly tried to retrieve bad parts from a "reclamation" area even after they were thrown out.

Boeing declined to comment on BI's queries, saying it would defer to the NTSB on the investigation. The FAA didn't immediately respond to a request for comment from BI, sent outside business hours.