With more countries grounding Boeing jets and with lawmakers, aviation workers and consumers calling on the United States to do the same, the head of the aerospace giant on Tuesday made a personal appeal to President Trump.
Boeing’s chief executive, Dennis A. Muilenburg, called from Chicago and expressed to Mr. Trump his confidence in the safety of the 737 Max 8 jets, according to two people briefed on the conversation. Two of the planes flown by overseas carriers have crashed in recent months in similar accidents.
The brief call had been in the works since Monday, but it came shortly after Mr. Trump raised concerns that the increasing use of technology in airplanes was compromising passenger safety. “Airplanes are becoming far too complex to fly,” he wrote on Twitter. “Pilots are no longer needed, but rather computer scientists from MIT.”
Soon after the conversation ended, Mr. Muilenburg received more bad news. The European Union suspended “all flight operations” of the Boeing 737 Max 8 model, a striking move by one of the industry’s important regulators. At the end of the day, the Federal Aviation Administration said that it was continuing with its review and that the planes could keep flying.
Yet the decision in Europe means roughly two-thirds of the Boeing Max 8 aircraft in the world have been pulled from use in the two days since the crash of an Ethiopian Airlines flight that killed 157 people. The swift actions by authorities around the world were driven in part by concerns about a connection to a similar disaster involving a Max 8 in Indonesia last October, when a Lion Air flight plunged into the Java Sea shortly after takeoff, killing all 189 people aboard.
[Boeing’s 737 Max 8 jets are grounded nearly everywhere. Here are lists by airline and country.]
By Tuesday afternoon, the United States was nearly alone among major countries still allowing the jets to fly.
Elaine Chao, the transportation secretary, said regulators “will not hesitate to take immediate and appropriate action” if a safety issue arises.
Boeing reiterated in a statement late Tuesday that it had “full confidence” in the 737 Max 8. It noted that the F.A.A. had taken no action and “based on the information currently available, we do not have any basis to issue new guidance to operators.”
Two United States airlines fly the 737 Max 8 aircraft and both said they planned to keep flying. Southwest Airlines has 34 of the planes and American Airlines has 24. The airlines have said they have analyzed data from their thousands of flights with the jets and found no reason to ground them.
“We don’t have any changes planned,” Southwest said in a statement. “We have full confidence in the aircraft,” American said.
The growing pressure left Boeing in an increasingly unfamiliar position. The company, a major military contractor, has close ties with the American government, and the F.A.A. in particular.
[Three generations of a Canadian family died in the Ethiopian plane crash.]
Boeing is a major lobbying force in the nation’s capital. Its top government relations official is a veteran of the Clinton White House, and last year, the company employed more than a dozen lobbying firms to advocate for its interests and spent $15 million in total on lobbying, according to the Center for Responsive Politics.
The company, through its political action committee, funnels millions of dollars into the campaign accounts of lawmakers from both political parties. A list of a year’s worth of political spending on Boeing’s website stretches on for 14 pages, listing campaign contributions to lawmakers ranging from a city councilman in South Carolina to Representative Nancy Pelosi of California, who is now the House speaker.
“Boeing is one of the 800-pound gorillas around here,” said Senator Richard Blumenthal, Democrat of Connecticut, who has called for the Max 8 to be grounded. As an example of Boeing’s reach in the highest levels of government, Mr. Blumenthal noted that the acting defense secretary, Patrick M. Shanahan, is a former Boeing executive.
[While some passengers balked, it was business as usual in the United States and Canada.]
For decades, the F.A.A. has used a network of outside experts, known as F.A.A. designees, to certify that aircraft meet safety standards. In 2005, the regulator shifted its approach for how it delegated authority outside the agency, creating a new program through which aircraft manufacturers like Boeing could choose their own employees to be the designees and help certify their planes.
The program is intended to help the F.A.A. stretch its limited resources, while also benefiting plane makers who are eager to avoid delays in the certification process.
The regulator maintains offices inside Boeing’s factories, including those in Renton, Wash., and in Charleston, S.C. “I’ve raised this concern in the past, about people who go to work at the Boeing plant who work for the F.A.A.,” said Representative Peter A. DeFazio, Democrat of Oregon and the chairman of the House transportation committee. “How much scrutiny are they applying, and could they be influenced?”
The F.A.A.’s top safety official, Ali Bahrami, has worked closely with Boeing during his career, directing the agency’s certification of the Boeing 787 Dreamliner and the 747-8 passenger and freighter models.
“It’s a very cozy relationship,” said Jim Hall, the former head of the National Transportation Safety Board. “The manufacturer essentially becomes both the manufacturer and the regulator, because of the lack of the ability of government to do the job.”
At a congressional hearing in 2015, a Boeing executive described the arrangement as effectively having an “arm of the F.A.A. within the Boeing Company,” and said 1,000 employees were part of the program.
The regulatory policy of allowing manufacturers to essentially sign off on the safety of their own products has drawn criticism in the past. In 2011, a report from the Transportation Department’s Office of Inspector General found that the “F.A.A. has significantly reduced its role in approving individuals who perform work on F.A.A.’s behalf by further delegating this approval to private companies.”
Boeing’s relationship with Mr. Trump has not always been smooth, however. Shortly after becoming president-elect, Mr. Trump assailed Boeing for the estimated cost of its program to build new Air Force One planes, which provide mobile command centers for the president.
The “costs are out of control, more than $4 billion. Cancel order!” Mr. Trump wrote on Twitter a month after winning the election, but before taking office. A couple of weeks later, Mr. Muilenburg visited Mr. Trump at his Mar-a-Lago club in Palm Beach, Fla., to try to smooth things over.
“It was a terrific conversation,” Mr. Muilenburg told reporters after the meeting, explaining that he had given Mr. Trump “my personal commitment” that Boeing would build new Air Force One planes for less than the $4 billion estimate. Weeks after the conversation, Boeing donated $1 million to Mr. Trump’s inaugural committee. The company had donated the same amount to help finance President Barack Obama’s inauguration in 2013.
As concerns about the airworthiness of the Boeing 737 Max 8 spread around the globe on Tuesday, pressure was building on the F.A.A. to take action. Boeing shares fell 6 percent on Tuesday, after falling 5 percent on Monday. Early on Wednesday in New Zealand, the country’s aviation regulator suspended 737 Max flights there.
Two unions representing flight attendants called for the jets to be grounded. “The F.A.A. must restore public confidence by grounding the 737 Max until the required changes have been implemented and the public can be fully assured,” said Sara Nelson, president of the Association of Flight Attendants.
Lori Bassani, the president of the Association of Professional Flight Attendants, which represents flight attendants at American Airlines, called on the airline to “strongly consider grounding these planes until a thorough investigation can be performed.”
In Washington, politicians on both sides of the aisle called for action. Senator Ted Cruz, the Texas Republican who is the chairman of the Senate Commerce Committee’s Subcommittee on Aviation and Space, said he wanted “to temporarily ground 737 Max aircraft until the F.A.A. confirms the safety of these aircraft.” He also said he planned to hold a hearing to investigate the crashes.
Senators Elizabeth Warren, Democrat of Massachusetts, and Mitt Romney, Republican of Utah, also called on the F.A.A. to ground the aircraft while the cause of the Ethiopian crash is investigated.
“Serious questions have been raised about whether these planes were pressed into service without additional pilot training in order to save money,” Ms. Warren said. Mr. Romney, in a Twitter post, urged a grounding “out of an abundance of caution for the flying public.”
In his phone call with the president, the Boeing chief, Mr. Muilenburg, outlined the company’s position since the crash. He also updated Mr. Trump on the status of the 737 Max models.
It was unclear whether anything came of the call. The White House did not respond to questions about the conversation.
In its statement, the F.A.A. said that it had “no basis to order grounding the aircraft.”