737 MAX design
flaw
Newsletter published on March 13, 2019
(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: https://theaircurrent.com/aviation-safety/what-is-the-boeing-737-max-maneuvering-characteristics-augmentation-system-mcas-jt610/
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.
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