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737 MAX design flaw, from Peter Myers

(1) Changes Boeing made from the 737-NG to the 737 MAX

(2) MAX engine is bigger, forward of Centre of Gravity - a design flaw, software can't remedy it

(3) U.S. pilots flying 737 MAX weren’t told about MCAS

(4)  Former Sec of Transportation who grounded 787 Dreamliner says FAA should Ground 737 MAX too


(1) Changes Boeing made from the 737-NG to the 737 MAX

This article explains the changes Boeing made to the 737, in order to compete with the new Airbus A320neo:

Much bigger engines on the MAX, in a more forward position, changed the aerodynamics of the 737, increasing the risk of stall.

MCAS (Maneuvering Characteristics Augmentation System) software & hardware were introduced to fix the problem. But MCAS malfunction has caused 2 crashes so far.

The article below has diagrams showing the changes from the 737-NG to the 737 MAX:

The MAX engine is bigger, but the landing gear, being unchanged, gives insufficient ground clearance, so the engine is placed further ahead of the wing.

(2) MAX engine is bigger, forward of Centre of Gravity - a design flaw, software can't remedy it

Peter Myers, March 13, 2019

The MAX engine is forward of the Centre of Gravity. But this is a design flaw. It destabilizes the aircraft, thus the software "fix".

I can't see why they couldn't have redesigned the landing gear instead, to give the required ground clearance even though using bigger engines.

Boeing will pay dearly for this.

Now passengers are demanding to switch flights:

Flight Attendants don't want to fly the 737 Max:

Boeing 737 MAX (unit cost $121m) has a design flaw; it will massively lose orders to

Airbus A320neo ($110m):

Irkut MC-21 (Russia) ($91m):

Comac C919 (China) (scheduled to start service in 2021):

Embraer E-Jet E2 ($60m):

and Boeing 737-NG ($106m)


(3) U.S. pilots flying 737 MAX weren’t told about MCAS

U.S. pilots flying 737 MAX weren’t told about new automatic systems change linked to Lion Air crash

Pilots for two U.S. airlines flying Boeing's 737 MAX weren't trained about a key change to an automatic system that's been linked to the fatal crash of a Lion Air jet last month, according to pilot representatives at both airlines.

By Dominic Gates

Seattle Times aerospace reporter

Pilots flying Boeing’s 737 MAX for American Airlines and Southwest Airlines were not informed during training about a key change to an automatic system that’s been linked to the fatal crash of a Lion Air jet last month, according to pilot representatives at both airlines.

Jon Weaks, president of the Southwest Airlines Pilots Association, said Monday the airline and the pilots “were kept in the dark.”

“We do not like the fact that a new system was put on the aircraft and wasn’t disclosed to anyone or put in the manuals,” he said in an interview. What’s more, he noted, Boeing and the Federal Aviation Administration have now warned “that the system may not be performing as it should.”

“Is there anything else on the MAX Boeing has not told the operators?” he added. “If there is, we need to be informed.” ...

Early Saturday morning, Capt. Mike Michaelis, chairman of the safety committee of the Allied Pilots Association (APA) at American Airlines, sent out a message to pilots informing them of details Boeing had shared with the airline about this new 737 MAX system  — called MCAS (Maneuvering Characteristics Augmentation System).

“This is the first description you, as 737 pilots, have seen,” the message from the pilots association at American reads. “It is not in the American Airlines 737 Flight Manual … nor is there a description in the Boeing FCOM (Flight Crew Operations Manual). It will be soon.”

The description of MCAS provided by Boeing states that the system is designed to activate only “during steep turns with elevated load factors and during flaps up flight at airspeeds approaching stall” and that it is “commanded by the Flight Control computer using input data from sensors and other airplane systems.”

Michaelis’ message told American pilots to familiarize themselves with the procedure for cutting off that system. “At the present time, we have found no instances of AOA anomalies with our 737 MAX8 aircraft. That is positive news, but it is no assurance that the system will not fail,” he wrote. ...

APA spokesman Dennis Tajer said Monday that the detail on the MCAS system “is new information for us.”

He said his training on moving from the old 737 NG model cockpit to the new 737 MAX consisted of little more than a one-hour session on an iPad. The airline doesn’t have simulators specific to the MAX model.

Apart from that, the only MAX-specific training was practicing cross-wind landings, which are trickier in the MAX because the wingtips have large downward-pointing strakes that might touch the ground in hard cross-winds.

But the cockpit displays and systems seemed identical, he said.

“We assumed they were mostly cosmetic differences,” said Tajer. “Why we weren’t informed of this, I don’t know. Pilots are calling us and asking.”

With the revelation that the MAX has a shift in the flight-control system not present on the earlier 737 models, he said, APA safety experts are in “aggressive exploratory mode” to find out all the ramifications.

“We want to know everything about the airplane that we are accountable to fly safely,” Tajer said.

At the “Pilots of America” online chat forum, one American Airlines pilot posted the APA message and then added a personal reaction:

“We had NO idea that this MCAS even existed. It was not mentioned in our manuals anywhere (until today). Everyone on the 737 had to go through differences training for the MAX and it was never mentioned there either,” the anonymous pilot posted. “I’ve been flying the MAX-8 a couple times per month for almost a year now, and I’m sitting here thinking, what the hell else don’t I know about this thing?”

News that Boeing had not informed the airlines of the change was first reported Monday by Bloomberg News.

The fact that U.S. pilots were not informed about the change means that almost certainly the Lion Air pilots too were unaware. ...


(4)  Former Sec of Transportation who grounded 787 Dreamliner says FAA should Ground 737 MAX too

Man Who Grounded Dreamliner Says FAA Should Ground 737, Too

The FAA is risking its reputation and public safety, says former U.S. Transportation Secretary Ray LaHood. He’s right.

By David Fickling 13 March 2019, 12:58 am AEST

It’s a daily miracle that the general public accepts the existence of the aviation industry.

Every day, around 100,000 flights take off and fly between towns and cities around the world, each carrying fuel with the stored energy of a cruise missile jammed up alongside scores of families, tourists, business-people and pets. That we tolerate and even welcome this state of affairs is a tribute to the generations of engineers and administrators — and regulators — who’ve made traveling by air safer than driving the car to the mall.

It’s tempting to declare that the vast and complex infrastructure undergirding the safety of modern aviation is unnecessary, as President Donald Trump argued on Twitter Tuesday: relates to Man Who Grounded Dreamliner Says FAA Should Ground 737, Too relates to Man Who Grounded Dreamliner Says FAA Should Ground 737, Too

Ultimately, though, this infrastructure supports the rock-solid reputation of the aviation industry. In continuing to stand squarely behind the Boeing Co. 737 Max 8 while its peer regulators take a more precautionary approach, the U.S. Federal Aviation Administration risks squandering that.

That’s not just the view of this columnist. It’s also the opinion of Ray LaHood, the former U.S. Secretary of Transportation who grounded the 787 Dreamliner following fires in its lithium-ion battery packs in 2013.

“The flying public has to be assured that these planes are safe, and they don’t feel that way now,” he said by phone Tuesday. “The Secretary of Transportation should announce today that these planes will be grounded until there is 100 percent assurance from Boeing that these planes are safe to fly, because unless they can give that assurance they’re not holding up their promise to be the top safety agency in the U.S.”

The U.K.’s Civil Aviation Authority Tuesday became the latest national air regulator to ground the Max 8 in the wake of Sunday’s crash of Ethiopian Airlines Group Flight 302. Authorities in China, Indonesia, Singapore, Australia and Malaysia have already made the move. With the U.K. move affecting Norwegian Air Shuttle ASA and TUI AG, two of the biggest airlines still operating the 737 Max outside the U.S., the time for the FAA to get on board is overdue.

LaHood’s experience is instructive. At the time, the 123-day grounding of the Dreamliner was seen as a potential disaster for Boeing, potentially costing hundreds of millions of dollars and resulting in delays and cancellations of orders. In the end, the costs proved to be “minimal,” according to the company, burnished away by insurance coverage and the magic of program accounting, as my colleague Chris Bryant has written.

Indeed, the baptism by fire experienced by the Dreamliner has allowed the plane’s real virtues to shine through. With the battery problem fixed, it’s emerged as a popular and fuel-efficient aircraft with an excellent safety record. Airlines have rushed to buy more, and the model already has more firm orders from customers than the 1,300 targeted at the time of its grounding.

That’s a lesson to the FAA. European regulators are readying to follow the U.K. in grounding 737 Max models there, a person familiar with the matter told Christopher Jasper of Bloomberg News Tuesday. Indonesia’s Lion Air, the carrier affected by the plane’s October crash, is planning to switch its $22 billion order to Airbus SE models instead, a separate person familiar with that proposal earlier told Bloomberg.

While other regulators and companies take action, the credibility of the FAA in holding out is teetering. U.S. transport agencies promise only to act on the basis of “substantial evidence,” but there’s clearly sufficient evidence already for a reasonable person to want to pause flights until there’s a clearer understanding of what is behind these crashes. Safety First

Only 10 full-sized aircraft types in regular passenger service have suffered major fatal crashes

Source: Boeing, news reports

Note: Aircraft without crashes to date not included: A380, A320neo, A340, A350, A220, 717, 787. "Major fatal crashes" classed as hull loss accidents with fatalities. Only Boeing and Airbus planes shown.

A full investigation by the National Transportation Safety Board would provide the most solid findings — but passengers cannot be expected to wait for the year or so that such a report would take, according to LaHood.

“You can’t wait a year. This needs to be dealt with immediately,” he said. “This is the most important thing the Department of Transportation can do, to protect people in all modes of transport.”

As my colleague Chris Bryant has written, nothing less than total transparency will deal with this problem now. When a criminal laced Tylenol-branded painkillers with cyanide in 1982, the safety-first approach taken by Johnson & Johnson won back the faith of customers and in the process launched a thousand crisis-management textbooks. The FAA and Boeing need to demonstrate that they, too, put no priority above safety — and fast.


-- Peter Myerswebsite: