
To Get Boeing 737 Max Flying, Global Consensus Will Be Hard - aaronbrethorst
https://www.nytimes.com/2019/05/23/business/boeing-737-max-faa-regulation.html
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blackflame7000
At least half of the public wont even know they are on a max. Boeing still
makes the 777 which is the safest aircraft of all time. With only one real
crash at london due to an engine problem (not Boeing) and an intentional crash
Malaysia 370. MCAS is frequently confused with a flight augmentation system
which isn’t true. It’s designed to counteract a confused pilot and if you look
at the history of the 737 NG some of the few crashes not from the vertical
stabilizer issue are from disorientation leading to a stall. Now granted
Boeing made serious mistakes in the implementation of MCAS (1 AoA sensor and
not checking for disagreement is a cardinal rule they broke) but I believe
that the plane will go on to be quite successful because this was a serious
learning moment.

~~~
salawat
>MCAS is frequently confused with a flight augmentation system which isn’t
true. This is demonstrably false. MCAS is a system in the same vein as the
MD-11's LSAS. In other words, a hack to ensure the the "piloting experience"
of the MAX stays as similar as possible to that of the 737 NG, despite the
fact the NG doesn't suffer from directional pitch instability at high AoA.

>It’s designed to counteract a confused pilot and if you look at the history
of the 737 NG some of the few crashes not from the vertical stabilizer issue
are from disorientation leading to a stall.

If pilots are so prone to stalling in an aircraft with no pitch instability
near critical AoA, it seems disingenuous to try to pitch the MAX with MCAS as
being "more safe" when the possibility exists that MCAS may need to be
disabled in flight; thereby resulting in the same pilot, in what is touted as
"the same piloting experience" as the NG, yet with the spectre of pitch
instability at high AoA, exacerbated by a tendency to pitch up even more if
power is added on at landing speeds if a go-around is required; that wasn't
there before. It is less-than-or-equal in terms of safety.

Will it be an effective plane? Yes. Will dealing with MCAS be seared into
pilots' minds? Yes.

Let's not misrepresent the machine though. It has issues. Issues that are at
the center of a regulatory and business clusterf*ck that never should have
happened. The poor engineering and business decisions created a plane with
potentially lethal failure modes, that were unsuccessfully communicated to
customer (airline) and operator(pilot) alike.

The MAX may be able to operate for the rest of it's relevant operational
lifetime, but it will never be a success. It'll be memorial to the height to
which greed, and contempt for the law, and hubris were elevated in the process
of designing this plane.

At the risk of waxing poetic:

The MAX will be as the Crow that caws at midnight. A somber reminder of the
banal parts of human nature against which we must remain ever vigilant, lest
they take the reins again in humanity's struggle to push ourselves passed the
limits that bind us.

~~~
blackflame7000
"MCAS is frequently confused with a flight augmentation system which isn’t
true. This is demonstrably false. MCAS is a system in the same vein as the
MD-11's LSAS. In other words, a hack to ensure the the "piloting experience"
of the MAX stays as similar as possible to that of the 737 NG, despite the
fact the NG doesn't suffer from directional pitch instability at high AoA."

\- This is false because MCAS only activates during stall conditions and is
the exact reason why this issue went undiscovered for so long. If it was the
system that you say it is, then it would have been constantly making the
2.5-degree adjustments to the horizontal stabilizer all the time! The fact is
that it requires an AoA sensor to report an attack angle greater than 25
degrees while airspeed drops below 200 knots. That Aircurrent article was the
worst thing for Boeing because it made so many people misinformed. It somehow
convinced people that the engine thrust is misaligned making it into some sort
of harrier-jet hybrid that's "unstable". Completely false. Look at how many
different engines and engine placements have been used throughout the history
of flight that didn't require any augmentation system and then tell me that
argument still has validity.

~~~
salawat
>This is false because MCAS only activates during stall conditions and is the
exact reason why this issue went undiscovered for so long. If it was the
system that you say it is, then it would have been constantly making the
2.5-degree adjustments to the horizontal stabilizer all the time!

"All the time" is a funny way of spelling "when the AoA sensor indicates an
AoA near or greater than critical."

Also, the problem took so long to be discovered because Trim has become
increasingly automated, relegating any system that modifies it to a second or
third order concern for pilots generally. The system wasn't documented
explicitly in training materials, and yes, what malfunctions did happen
generally happened in less critical phases of flight, and we're quickly
recovered from.

>The fact is that it requires an AoA sensor to report an attack angle greater
than 25 degrees

...Okay, you didn't even look at the Flight Data Recorder of either crash did
you? The same data that shows MCAS happily driving 300+ people into the
lithosphere at 300+ knots?

MCAS activates regardless of speed. The key input is AoA, flap setting, and
whether the autopilot is on, and altitude > 450 AGL if I recall correctly.
Furthermore, it ramps up over sequential activations. I'm open to entertaining
some possibility that you just didn't look it up, but your arguments are
straying into areas if incorrectness that seem to indicate your sources may
need to be reevaluated.

I implore you to do some more thorough research.

Search terms: ET302 FDR data ET302 prelim report Lion Air 610 FDR data MCAS
Flight Control Systems.

I understand Aviation isn't the lightest topic of research, but that's also
why it's so important to make sure you're reasoning from the right
information. Flying is complicated. Not inaccessibly so, but definitely beyond
normal intuition at times.

~~~
blackflame7000
"Also, the problem took so long to be discovered because Trim has become
increasingly automated, relegating any system that modifies it to a second or
third order concern for pilots generally."

> "The problem with automated runaway trim is that trim is automated and
> pilots don't notice" \- your argument in a nutshell

"The fact is that it requires an AoA sensor to REPORT an attack angle greater
than 25 degrees"

> Who said the report needed to be accurate?

