The US government has ordered Boeing's 737 Max grounded, marking an about-face for the Federal Aviation Administration that, as recently as last night, declined such a move despite a building worldwide wave of 737 Max groundings.
That wave reached the US border earlier on 13 March, when Canada – which had until then stood beside the USA in not taking action – issued its own grounding.
"We are going to be issuing an emergency order of prohibition to ground all flights of the 737 Max 8 and the 737 Max 9," President Donald Trump said on 13 March.
The grounding follows the 10 March crash of an Ethiopian Airlines 737-8 and the October 2018 crash of a Lion Air aircraft of the same type. Those crashes killed a combined 346 people.
The US move brings the FAA in-line with agencies worldwide, but marks a break with Boeing, which has steadfastly insisted the 737 Max is safe.
Trump announced the ban after speaking with FAA acting director Daniel Elwell, transportation secretary Elaine Chao and Boeing chief executive Dennis Muilenburg.
"They are all in agreement with the action," Trump says. "Any plane currently in the air will go to its destination and thereafter be grounded until further notice."
The FAA issued a statement saying it "is ordering the temporary grounding of Boeing 737 Max aircraft operated by US airlines or in US territory. The agency made this decision as a result of the data gathering process and new evidence collected at the site and analysed today."
"This evidence, together with newly refined satellite data available to FAA this morning, led to this decision," the FAA adds. "The grounding will remain in effect pending further investigation, including examination of information from the aircraft’s flight data recorders and cockpit voice recorders."
In statement, Chicago-based Boeing says: "Boeing continues to have full confidence in the safety of the 737 Max. However, after consultation with the US Federal Aviation Administration, the US National Transportation Safety Board 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."
“We are supporting this proactive step out of an abundance of caution," the airframer adds. "Safety is a core value at Boeing… We are doing everything we can to understand the cause of the accidents."
The grounding will affect three major US carriers: American Airlines, which operates 24 737-8, Southwest Airlines with 34 of the same type, and United Airlines with 14 737 Max 9s, Cirium's Fleets Analyzer data shows.
"We appreciate the FAA’s partnership, and will continue to work closely with them, the Department of Transportation, National Transportation Safety Board and other regulatory authorities," American says in a statement. "Our teams will be working to rebook customers as quickly as possible, and we apologise for any inconvenience."
Southwest and United issued similar statements.
Shortly before the US grounding of the 737 Max was announced, Panama's Copa Airlines said it would ground its six 737 Max 9s. "Copa Airlines reiterates that its six Max 9 aircraft have completed approximately 1,400 flights and over 7,700 flight hours with excellent reliability and performance results," says the airline.
The FAA faced criticism for its slow response even before yesterday, when it issued another notice saying it had no evidence to warrant grounding the Max.
Boeing bolstered its public responses with that fact, noting in an 11 March statement, "It is important to note that the FAA is not mandating any further action at this time".
But some US politicians urged the FAA ground the Max, as has the Association of Professional Flight Attendants, which represents cabin crew at American.
"I remain concerned that international aviation regulators are providing more certainty to the flying public by grounding the 737 Max 8 than our own FAA," Peter DeFazio, chairman of the US House transportation and infrastructure committee says in a statement.
On 11 March, the FAA revealed that Boeing was in the process of updating the 737 Max's manoeuvring characteristics augmentation system (MCAS) following the Lion Air crash five months ago.
Investigators have said the aircraft went down while the pilots were fighting MCAS, which is new on the Max compared to older 737 models and was pushing the aircraft's nose down. Regulators have said MCAS can wrongly push down the nose if it receives erroneous angle-of-attack indications.
The updates are designed to limit "stabiliser trim commands in response to an erroneous angle of attack reading" and to "limit to the stabiliser command in order to retain elevator authority", Boeing said in an 11 March statement.
Boeing has said longstanding cockpit procedures will rectify a software issue suspected of playing a role in the Lion Air crash. Investigators have not said if that software played any role in the Ethiopian crash.