• At least two pilots, flying United States routes on the same model of Boeing jet involved in two recent crashes, filed incident reports with the federal government that raised concerns about safety and criticized a lack of training on the new plane, the Boeing 737 Max 8.
• Much of the world, including the European Union, China and India — but not the United States — has banned flights of the Boeing 737 Max 8 since a crash on Sunday in Ethiopia killed more than 150 people, the second such crash in the past six months.
• The Canadian carrier Sunwing became the first airline in Canada or the United States to suspend operations of the plane, though it said it had not done so for safety reasons.
• Investigators are still waiting for information from Ethiopian Airlines Flight 302’s voice and data recorders, which were recovered from the crash site on Monday. The airline’s chief executive, interviewed by CNN, said the pilots had told air traffic control they were having “flight control problems.”
Pilots on U.S. routes had reported concerns about the Max 8
At least two pilots who flew Boeing 737 Max 8 planes on routes in the United States had raised concerns in November about the noses of their planes suddenly dipping after engaging autopilot, according to a federal government database of incident reports.
The problems the pilots experienced appeared similar to those preceding the October crash of Lion Air Flight 610 in Indonesia, in which 189 people were killed. The cause of that crash remains under investigation, but it is believed that inaccurate readings fed into the Max 8’s computerized system may have made the plane enter a sudden, automatic descent.
In both of the American cases, the pilots safely resumed their climbs after turning off autopilot. One of the pilots said the descent began two to three seconds after turning on the automated system.
“I reviewed in my mind our automation setup and flight profile but can’t think of any reason the aircraft would pitch nose down so aggressively,” the pilot wrote.
A pilot on a separate flight reported in November a similar descent and hearing the same warnings in the cockpit, and said neither of the pilots on board were able to find an inappropriate setup.
“With the concerns with the MAX 8 nose down stuff, we both thought it appropriate to bring it to your attention,” the pilot said.
The complaints were listed in a public database maintained by NASA and filled with thousands of reports, which pilots file when they encounter errors or issues. The database does not include identifying information on the flights, including airline, the pilot’s name or the location.
Another pilot wrote that they had been given insufficient training to fly the Max 8, a new, more fuel-efficient version of Boeing’s best-selling 737.
“I think it is unconscionable that a manufacturer, the F.A.A., and the airlines would have pilots flying an airplane without adequately training, or even providing available resources and sufficient documentation to understand the highly complex systems that differentiate this aircraft from prior models,” the pilot wrote.
The pilot continued: “I am left to wonder: what else don’t I know? The Flight Manual is inadequate and almost criminally insufficient.”
Boeing has said the planes are safe to fly, but has pledged to upgrade their software and improve pilot training.
Citing global bans, Canadian airline grounds jets
Sunwing, a Canadian carrier, said on Tuesday that it was temporarily grounding its four Boeing 737 Max 8 aircraft even though Canada’s government, like that of the United States, has not ordered the move.
In a statement, the company said the step was “unrelated to safety.” Instead, the airline said, the move was prompted by growing airspace bans by countries and “evolving commercial reasons.”
The European Union on Tuesday joined the governments of the United Arab Emirates, Malaysia, Australia, New Zealand, Fiji, Singapore and other countries in suspending all Max 8 flights into or out of their airports. At least 34 airlines have now grounded the model, which means roughly two-thirds of the Max 8 planes in operation are now idled.
The Federal Aviation Administration in the United States has resisted pressure to ground the Max 8.
[We answered readers’ questions about the Boeing 737 Max 8.]
U.N. aviation agency takes no action on Max 8, for now
While regulators in much of the world have ordered temporary groundings of the Boeing 737 Max 8 as a precautionary measure, the United Nations civil aviation agency said it would await definitive findings about what went wrong on Ethiopian Airlines Flight 302.
“Once the final report into this accident is available we will have verified and official causes and recommendations to consider,” the agency, the International Civil Aviation Organization, said in a statement on Tuesday.
“In the meantime ICAO recognizes the right of those national governments who may choose to act on the limited information currently available by taking immediate flight safety precautions regarding 737 Max 8 operations,” it said.
The agency, based in Montreal, manages the Convention on International Civil Aviation, the agreement that ensures safe and orderly air travel around the world. According to its website, the agency, which has sanction powers to enforce compliance with the convention, works with United Nations member states and industry groups “in support of a safe, efficient, secure, economically sustainable and environmentally responsible civil aviation sector.”
Pilots reported ‘flight control problems,’ airline C.E.O. says
The pilots of Ethiopian Airlines Flight 302 reported to air traffic control that they were having “flight control problems” in the moments before the crash, the airline’s chief executive was quoted as saying in an interview with CNN.
The quoted remarks on Tuesday from the chief executive, Tewolde GebreMariam, suggested the plane had not responded to actions by the pilots.
Mr. GebreMariam was also quoted as saying the black boxes recovered from the wreckage “will be sent overseas” and not analyzed in Ethiopia. He did not specify where they would be taken.
Concerns arose about the Max 8’s flight control systems in October after one of the planes, Lion Air Flight 601, crashed in Indonesia soon after takeoff, leaving 189 people dead.
Russell Goldman, Daniel Victor, Ian Austen and Rick Gladstone contributed reporting.
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