WASHINGTON _ The U.S. travel system braced for possible disruption after President Donald Trump and the FAA on Wednesday grounded Boeing's 737 Max planes indefinitely in response to two deadly crashes involving the jetliner.
The United States had been the last major holdout in letting the planes continue to fly, with dozens of other nations having grounded the twin-engine jetliner as a precautionary safety move.
But hours after Canada join the nations grounding the 737 Max, Trump did the same, saying the "safety of the American people and all people is our paramount concern."
"All of those planes are grounded, effective immediately," Trump said during a meeting at the White House, adding that the roughly three dozen flying at the time would be parked after their flights ended.
After Trump's announcement, the Federal Aviation Administration said it made the decision "as a result of the data-gathering process and new evidence collected at the site and analyzed today," referring to the site of an Ethiopian Airlines 737 Max crash after takeoff in Ethiopia on Sunday that killed all 157 people aboard.
The three U.S. airlines that fly the 737 Max _ Southwest, American and United _ said they would comply with the order and were working to rebook passengers.
Southwest, with 34 of the affected planes, said customers booked on canceled 737 Max flights could rebook. There will be no additional fees or fare differences for travelers who rebook within 14 days of their original travel date between their original destinations, Southwest said.
American, with 24 planes affected, and United, with 16, also said they would work with customers to minimize disruptions. American noted that it operates 85 flights with the 737 Max out of 6,700 total departures in its system.
United, noting that the 737 Max accounts for about only 40 of its flights daily, said that "we do not anticipate a significant operational impact as a result of this order."
Daniel K. Elwell, acting administrator of the FAA, told CNBC that the decision was made based on enhanced satellite data that showed the track of the Ethiopian Airlines flight was "very close" to that of a Lion Air 737 Max flight that crashed off Indonesia in October.
"We don't make decisions about grounding aircraft ... without actionable data. In this case the actionable data did not arrive until today," Elwell said.
Initial data about the Ethiopian Airlines flight track was "very incomplete" and "raw," he said. The flight took place in an area that is not served by radar, so the FAA used satellite data that had to be enhanced.
Elwell said the decision to ground the Boeing 737 Max airliners was his, but "because of the magnitude of this action," he consulted with Trump and Transportation Secretary Elaine Chao "along the way." They agreed with his decision, Elwell said.
The FAA now is awaiting data from the black box of the Ethiopian Airlines plane as the agency decides how long to keep the 737 Max airliners grounded.
Flightradar24, a website that tracks air traffic, tweeted a map showing the 737 Max planes in the air at the time of Trump's announcement.
Aviation observers have raised questions about the Max version of the 737, which is the most-produced aircraft in Boeing's line of jetliners, with more than 5,000 on order worldwide.
The Air Line Pilots Association said it supported the decision to ground the planes and called on "investigative authorities responsible to expedite the investigation of Ethiopian Airlines Flight 302 and identify any corrective action if necessary in order to return this aircraft to service."
Trump's decision came after he spoke on the phone Tuesday with Boeing Chief Executive Dennis Muilenburg following the president's tweet that airplanes were "becoming far too complex to fly." Boeing confirmed that Muilenburg told the president the 737 Max was safe but declined to elaborate on the call.
Aviation authorities in Europe, India, China and elsewhere grounded the plane in the aftermath of the crash of the Ethiopian Airlines jet and the Lion Air disaster, both of which involved the 737 Max.
Canadian Transport Minister Marc Garneau told reporters that Canada banned the plane from operating in the country, or flying over it, because of inconclusive data suggesting similarities between the crashes.
Boeing said Wednesday it had "full confidence in the safety of the 737 Max. However, after consultation with the U.S. Federal Aviation Administration (FAA), the U.S. National Transportation Safety Board (NTSB), and aviation authorities and its customers around the world, Boeing has determined _ out of an abundance of caution and in order to reassure the flying public of the aircraft's safety _ to recommend to the FAA the temporary suspension of operations of the entire global fleet of 371 737 Max aircraft."
Boeing's stock, meanwhile, stabilized after dropping sharply Monday and Tuesday, wiping out $30 billion of its total market value. The stock edged up Wednesday $1.73, or 0.5 percent, to $377.14 a share.
The last time the FAA ordered a plane grounded was in 2013. The agency ordered airlines to cease operations of Boeing's then-new 787 Dreamliner after five fires in five days originating in the plane's lithium ion battery. None of the planes crashed, and Boeing implemented a fix for the battery overheating problem. The plane has gone on to be a mainstay of airlines worldwide.
Before Trump acted, the FAA had not grounded the aircraft, saying Tuesday that the agency had found "no basis" for taking such action.
The FAA and Garneau's agency work closely on most aviation matters, but, Garneau said, "we make our own decisions in Canada and occasionally those decisions may be different from our colleagues south of the border."
"They're aware of it and the reasons for it," Garneau said of the FAA's and Canada's decisions, "and similarly they let us know when they have a difference of opinion."
When asked what would persuade Canada to lift the ban, Garneau replied, "The smoking gun that will explain what happened with this particular flight" in Ethiopia.
"We'll find out, hopefully, in the coming days how that aircraft behaved" after authorities review the doomed jetliner's flight recordings, Garneau said.
Meanwhile, the mounting concerns reportedly have prompted some airlines to reconsider their 737 Max orders.
Kenya Airways is re-evaluating plans to buy the plane and might switch to the rival Airbus A320 or upgrade to Boeing's larger 787 Dreamliner, Bloomberg reported the carrier's chairman, Michael Joseph, as saying.
In addition, Indonesia's Lion Air is moving to drop a $22 billion order for the 737 in favor of the Airbus model, Bloomberg reported an unidentified source as saying.
It was the Lion Air crash on Oct. 29, which killed 189 people, that first raised questions about the aircraft, and analysts have focused on software in the new jetliner intended to stop the plane from stalling.
But maintenance issues and possible pilot error related to the software also are being evaluated, and the crash remains under investigation.
The union for American Airlines' pilots, the Allied Pilots Association, said Tuesday that American's 737 Max planes were unique because they were the only ones equipped with two displays, one for each pilot, related to the software in question. That provides "an extra layer of awareness and warning," the union said.
The union said it "remains confident in the Boeing 737 Max and in our members' ability to safely fly it."
The FAA also had been criticized by some analysts, politicians and others for not joining Canada and other nations initially in grounding the 737 Max while awaiting more clarity about the cause of the crashes.
But John Cox, a retired airline pilot and accident investigator, had defended the agency. In an op-ed column in the Los Angeles Times, Cox wrote that "the FAA is right to wait. While both accidents are tragic, it's not at all clear that they have the same cause."
