BEIJING — When China on Monday became the first country to order all Boeing 737 Max 8 planes grounded in the aftermath of an Ethiopian Airlines crash Sunday, its aviation regulator sent an unmistakable signal: The U.S. Federal Aviation Administration is no longer the only authority in civil aviation worldwide.

After China ordered a dozen carriers to ground their 96 planes — about a quarter of all 737 Max aircraft in operation globally — authorities in Ethi­o­pia, Indonesia, Mongolia, Morocco and Singapore quickly followed suit, along with carriers in Latin America and South Korea.

Despite the FAA issuing a statement backing the Boeing jet’s airworthiness, the European Union grounded the model Tuesday, as did at least 10 other countries, with authorities saying the aircraft would not be allowed to fly to or from their countries pending the investigation.

European aviation officials break with FAA and Boeing and ground 737 Max 8 aircraft involved in crash

China’s move, unprecedented for a government that once took cues from the FAA, was motivated by what Chinese officials and pilots said was months of equivocation from U.S. officials and Boeing in response to safety inquiries from China after a 737 Max 8 flight crashed in Indonesia in October. 

The move by China and a growing number of national authorities could raise the stakes for Boeing and U.S. officials even while the crash investigation in Ethi­o­pia is in its early stages.

“The differences of opinion will add to the pressure on the FAA to share their reasoning and what they’re proposing to do,” said Andrew Herdman, director general of the Association of Asia Pacific Airlines.

Investigations of both the Ethiopian and Indonesian crashes are ongoing; the FAA said Monday that it has a team in Ethi­o­pia at the site of the wreckage. The agency said it will mandate a software fix in the coming weeks to the jet’s automation.

A top official with the Civil Aviation Administration of China (CAAC) said Monday that the Chinese asked their counterparts at the FAA as well as Boeing about piloting software and safety issues concerning the popular new airliner model after Lion Air Flight 610 plunged into the sea off Indonesia last fall, but that they have not received satisfactory answers.

Aviation experts said issues with the 737 Max’s new piloting software, the Maneuvering Characteristics Augmentation System (MCAS), and angle-of-attack sensors may have played a role in both accidents, which occurred less than five months apart. Boeing issued notices to pilots worldwide about the MCAS after the Lion Air crash but has been criticized for not doing so sooner — or more thoroughly.

“They have had difficulty making a decision, so we took the lead,” CAAC Deputy Director Li Jian told reporters in Beijing, referring to a lack of stronger FAA measures regarding the 737 Max. Li added that the plane’s software may encounter serious problems when coupled with unreliable sensor readings and suggested that this has been happening to Chinese pilots.

“These kinds of situations have already happened many times,” Li said, without giving more details, according to state media. China will resume 737 Max flights after it has received sufficient safety guarantees from Boeing, he added, but there was a risk now that Chinese pilots “didn’t dare to fly, and weren’t able to fly” the plane.

Pilots unable to correct for faulty sensor that sent Indonesian flight plunging into the sea, report says

The FAA said Monday that it stood by the 737 Max’s airworthiness and “has not been provided data to draw any conclusions or take any actions,” including grounding the model. Boeing China said on its Weibo social media account that a software fix would be made in several weeks.

Experts widely caution that investigators have not drawn parallel links between the Ethio­pian and Lion Air crashes, and China’s move to immediately ground its entire fleet while the Ethiopian investigation was barely underway diverged from industry and regulatory norms.

China’s decision may be at least partly politically influenced by its trade tensions with the United States, said Neil Hansford, an aviation consultant at Strategic Aviation Solutions in Sydney. 

Li was asked about trade tensions Monday and denied that his agency was politically motivated, calling the U.S. trade dispute a “separate matter.”

Hansford, who has spoken to pilot unions about their concerns flying the Boeing plane, said Chinese authorities had ample justification to move first. The FAA has shown reluctance to take tough action against a major American manufacturer, he said.

“It’s not hard to be ahead of the FAA,” Hansford said. “If this had been an Airbus plane, the FAA would’ve been all over it.” Airbus is based in Europe.

Chinese pilots and industry observers say Boeing sent a two-page notice to pilots worldwide about the MCAS system after the Lion Air crash. But it has not recommended widespread additional training programs or simulations, at least in China.

Carl Liu, a 23-year-old pilot who has been flying 737s since June for a Chinese domestic airline, said the new model would sometimes show that the aircraft was climbing steeply, even though it was climbing by 10 degrees, and automated systems would nudge the plane’s nose down, causing a temporary loss of control.

“I’ve noticed there is a great deal of error in the MCAS system, so it’s not a one-off incident,” said Liu, who spoke to The Washington Post on the condition that his employer not be identified. “Boeing has not done enough; it never thought about suspending the production or operation of its 737 Max 8 planes even after recurring tragedies.”

He added that “all Boeing has promised is to update the MCAS system, and even that small move came a little too late.”

What Liu describes is similar to what investigators in their preliminary findings said caused the Lion Air crash, in which a malfunctioning sensor made the plane plummet repeatedly as the pilots struggled to regain control. The pilots were unable to even ascertain their speed and altitude because the system was showing erroneous readings, according to the findings.

The second 737 Max 8 crash has opened up raw wounds for families and friends of those who perished in the waters off Jakarta.

“I am saddened to know that [the] aviation industry was waiting for the incident to happen again to awaken themselves that Boeing is playing with lives of pilots,” said Garima Sethi, wife of Bhavye Suneja, the captain of Lion Air Flight 610.

Although pilots have expressed wariness about the new jet, there is disagreement in Chinese aviation circles about whether it amounts to a design flaw. Chen Jianguo, head of technology at the Aircraft Owners and Pilots Association of China, said all Chinese 737 Max pilots were notified about the MCAS system and its quirks after the Lion Air crash.

“There’s no need for more broad training about MCAS and how to turn it off,” he said by telephone. “You just need one or two seconds to turn it off.”

Herdman, of the Association of Asia Pacific Airlines, said Boeing may be limited in what information it can convey to international authorities because of protocols governing what manufacturers may say while investigations are in progress.

But authorities who have grounded the planes and those who haven’t were both acting in good faith, he said.

“We’re seeing both forms of decision-making, a more deliberative, analytical, measured way and a more reactive, intuitive way,” Herdman said. “We just need to be careful the public doesn’t become unduly alarmed.”

Yang Liu, Lyric Li and Yuan Wang in Beijing; Paul Schemm in Addis Ababa, Ethi­o­pia; and Shibani Mahtani in Hong Kong contributed to this report.

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Today’s coverage from Post correspondents around the world

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