US and Canada Ground the Boeing 737 MAX 8 Aircraft

The United States and Canada have joined with much of the world in grounding the Boeing 737 MAX 8 aircraft after the crash of Ethiopian Airlines flight 302.
John Loeffler

After days of resisting calls to ground Boeing’s 737 MAX 8 aircraft, President Donald Trump announced today that all Boeing 737 MAX 8s in the United States would be grounded shortly after Canada’s aviation authority announced that they were closing Canadian airspace to the aircraft.

Boeing 737 MAX 8 Grounded

Boeing 737 MAX 8
Source: Boeing

Increasingly isolated from the rest of the world, President Donald Trump announced today that all Boeing 737 MAX 8s flown in and out of the United States would be grounded once they had landed, after Canada announced that it was closing its airspace to the aircraft after satellite data added new evidence that raised questions about the plane's airworthiness.

"The advice the experts have provided is based on the information they have been receiving," said Canadian Transport Minister Marc Garneau in a statement announcing the groundings, "the requirements for new procedures and training for Boeing 737 MAX 8 and 9 flight crews they have already put in place; and the latest information available from the incidents."

The US Federal Aviation Authority (FAA) issued a statement on the groundings shortly after 3 PM this afternoon: "The FAA is ordering the temporary grounding of Boeing 737 MAX aircraft operated by U.S. airlines or in U.S. territory.” the agency said in a statement. “The agency made this decision as a result of the data gathering process and new evidence collected at the site and analyzed today. This evidence, together with newly refined satellite data available to FAA this morning, led to this decision."

The announcement comes as the United States and Canada became increasingly isolated from the rest of the world in refusing to ground the aircraft after the crash of Ethiopian Airlines flight 302 out of Addis Ababa, Ethiopia on Sunday.


Similarities Seen In The Two Crashes

Lion Air 737 MAX 8
Source: Bathara Sakti / Flickr

Ethiopian Airlines flight 302 was the second crash of the Boeing 737 MAX 8 in less than six months and bore unnerving similarities to its first crash on October 29th, 2018.

That crash, Indonesia’s Lion Air flight 610, is still under investigation, but preliminary findings show that the plane appears to have suffered from a software bug that initiated the plane’s anti-stall software during takeoff. This forced the nose of the plane downward, which the pilots tried unsuccessfully to resist.

The resulting tug of war with the autopilot system caused the plane to dip dozens of times, according to the investigation, and was likely responsible for the crash.

Ethiopian Airlines 737 MAX 8
Source:  Boeing, via Q13


Initial reports seemed to show that Ethiopian Airlines flight 302 suffered from the same software bug and subsequent tug of war as Lion Air 610, prompting nations and airlines around the world to start grounding the Boeing 737 MAX 8.

Until today, the United States and Canada were resisting calls to ground the aircraft even as officials expressed concerns about the reported similarities between the two crashes.

Software Defect Appears To Be To Blame, Reported By Pilots

The autopilot software that is suspected of malfunctioning had been identified as early as January as a problem in need of a fix. Officials at Boeing and US federal regulators had been trying to resolve a dispute over the scope of the necessary changes, which contributed to the delay of the software update to this April.

The US Government shutdown in January is also cited as a reason for the delay according to the Wall Street Journal, who first reported on the dispute between Boeing and Federal safety officials back in February.

However, recent reporting shows that US pilots have reported problems with the 737 MAX 8 aircraft. A search of the US Aviation Safety Reporting System, where pilots can anonymously report problems with specific aircraft without fear of reprisal, show at least two reported cases where pilots experienced incidents similar like the one that appears to have precipitated the crash of Lion Air 610 and possibly Ethiopian Airlines flight 302.

Boeing 737 MAX 8 Takeoff
Source: Boeing

“The aircraft accelerated normally and the Captain engaged the 'A' autopilot after reaching set speed,” reads one report. “Within two to three seconds the aircraft pitched nose down bringing the VSI to approximately 1,200 to 1,500 FPM. I called 'descending' just prior to the GPWS sounding 'don't sink, don't sink.'

“The Captain immediately disconnected the autopilot and pitched into a climb. The remainder of the flight was uneventful. We discussed the departure at length and 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.”

Another report is even more alarming: “I looked at and engaged A Autopilot. As I was returning to my PFD (Primary Flight Display) PM (Pilot Monitoring) called ‘DESCENDING’ followed by almost an immediate: ‘DONT SINK DONT SINK!’

“I immediately disconnected AP (Autopilot) (it WAS engaged as we got full horn etc.) and resumed climb. Now, I would generally assume it was my automation error, i.e., aircraft was trying to acquire a miss-commanded speed/no autothrottles, crossing restriction etc., but frankly neither of us could find an inappropriate setup error (not to say there wasn't one).

“With the concerns with the MAX 8 nose down stuff [emphasis added], we both thought it appropriate to bring it to your attention.”

The problem apparently goes beyond just the autopilot software feature and into the guidance issued to pilots regarding the autopilot issue, which appears to have been known prior to the crash of Ethiopian Airlines flight 302.

In describing how the Maneuvering Characteristics Augmentation System (MCAS) engages the anti-stall function of the autopilot system, one pilot reports that the conditions where the system engages is not fully described by the issued flight manuals and directives to pilots.

“The recently released 737 MAX8 Emergency Airworthiness Directive directs pilots how to deal with a known issue, but it does nothing to address the systems issues with the [Angle of Attack] system.”

The report concludes after describing when the system engages: “This description is not currently in the 737 Flight Manual Part 2, nor the Boeing FCOM, though it will be added to them soon. This communication highlights that an entire system is not described in our Flight Manual. This system is now the subject of an [Airworthiness Directive].


“I think it is unconscionable that a manufacturer, the FAA, 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 fact that this airplane requires such jury rigging to fly is a red flag. Now we know the systems employed are error prone--even if the pilots aren't sure what those systems are, what redundancies are in place, and failure modes.

“I am left to wonder: what else don't I know? The Flight Manual is inadequate and almost criminally insufficient [emphasis added]. All airlines that operate the MAX must insist that Boeing incorporate ALL systems in their manuals.”

Questions Over Delay

Boeing, a major US-based manufacturer, has long standing ties with the US government and the FAA both because of military aircraft manufactured by the company  and its historic and ongoing role in the US space program. At least one Senator, who it should be pointed out has announced that she is running for President against Pres. Trump in 2020, and at least one news commentator have openly questioned whether the delay of the grounding of the 737 MAX 8 was the result of Boeing's closeness with the Trump Administration.

For it's part, Boeing has said it now supports the grounding of its aircraft as a precautionary measure.

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