Boeing 737 Max design error

On Monday, May 6, 2019 at 3:28:36 AM UTC-4, Jan Panteltje wrote:

On a sunny day (Sun, 5 May 2019 23:13:13 -0700) it happened Banders
snap@mailchute.com> wrote in <qaoj9p$1jpn$1@gioia.aioe.org>:

On 05/05/2019 08:25 PM, omnilobe@gmail.com wrote:
Weight and Balance of the 737 Max.

I looked at photos of 737 and 737 Max. The 737 has the front of
the engine at the front of the wing. The Max has the rear of the engine at the front of the wing. That makes it stall easily.
Actually, tail-heavy makes for an easy stall, and nose-heavy makes for a
dive. The crash planes weren't stalling, the AOA sensors just thought
they were. So you have it backward.

This photo should put your mind at ease.
https://www.colombotelegraph.com/wp-content/uploads/2019/03/Crash-Animation-of-Ethiopian-Airlines-flight-ET302-Boeing-737-Max-pl
ane.jpg

Normally software is tested and debugged, crashes happen,
bit of a nono to debug it in flights that carry people.

By all indications it was not a software bug, from everything we've
seen the software did what the aerodynamic engineers and others spec'd
it to do. And it all was tested, including by test pilots, for
certification, including in extreme situations, where MCAS would be
involved. Apparently having a stuck AOA sensor wasn't part of the
testing.

My opinion is that such software should be written by pilots,
not by spaced out no flying experience people.

That's ridiculous and what evidence do you have that the software developers
were spaced out? Aeronautical engineers and pilots certainly should have
been involved with what MCAS was and the specs for how it should operate.
This failure is clearly on them and the FAA. Could some software team
people have weighed in on some aspects of it? Sure. Like you'd think
someone might have said that part of the software should do a functional
test while the plane is still on the ground, to verify that the reading
from the AOA is normal there. And maybe they did, we won't know what all
went on until it's all been investigated. Also, whoever was writing that
code, that code module might not have access to the necessary data to
even know if the plane had just been started up, was still on the ground,
etc. and without that, you couldn't check.

Bottom line, people that were responsible, were knowledgeable at Boeing
and FAA were OK with this half-assed design where a single failed sensor
could shove the nose down, repeatedly. They considered it a serious
malfunction and evaluated the probabilities of various failures that
could cause it, by that measure, it met FAA and industry safety guidelines.
Another question in all this is what the root cause failure was? We've
heard nothing of that from either crash, which is very weird. These were
two sensors in two new planes that someone failed or were damanged, etc.
What exactly happened? You'd think they would suspect say a manufacturing
defect or something and have out a directive to inspect, replace, all
the similar AOAs out there.

I have bluntly refused to write code for things that I could not use myself.

Well, thankfully we have plenty of others willing or we'd be screwed.

Boeing and Trump standing there 'selling' it when whe got elected...
Does anybody see the link?

No

 

On Monday, May 6, 2019 at 4:57:15 AM UTC-4, Cursitor Doom wrote:

On Mon, 06 May 2019 08:30:50 +0000, Jan Panteltje wrote:

Like Trump University, normally somebody would get jailed for running a
fake university and handing out fake certificates?

Dunno about that, but I *do* know Obama posted a crudely-forged birth
certificate on the WH website, so maybe Trump is simply following a
recently-established precedent. :-D

What do you expect? If you aren't of this Earth, you have to produce some sort of document.

--

Rick C.

+ Get a 1,000 miles of free Supercharging
+ Tesla referral code - https://ts.la/richard11209

 

On Monday, May 6, 2019 at 3:52:38 AM UTC-4, bitrex wrote:

On 5/6/19 3:28 AM, Jan Panteltje wrote:
On a sunny day (Sun, 5 May 2019 23:13:13 -0700) it happened Banders
snap@mailchute.com> wrote in <qaoj9p$1jpn$1@gioia.aioe.org>:

On 05/05/2019 08:25 PM, omnilobe@gmail.com wrote:
Weight and Balance of the 737 Max.

I looked at photos of 737 and 737 Max. The 737 has the front of
the engine at the front of the wing. The Max has the rear of the engine at the front of the wing. That makes it stall easily.
Actually, tail-heavy makes for an easy stall, and nose-heavy makes for a
dive. The crash planes weren't stalling, the AOA sensors just thought
they were. So you have it backward.

This photo should put your mind at ease.
https://www.colombotelegraph.com/wp-content/uploads/2019/03/Crash-Animation-of-Ethiopian-Airlines-flight-ET302-Boeing-737-Max-pl
ane.jpg

Normally software is tested and debugged, crashes happen,
bit of a nono to debug it in flights that carry people.

My opinion is that such software should be written by pilots,
not by spaced out no flying experience people.

I have bluntly refused to write code for things that I could not use myself.

Ever write the code for an artificially intelligent sex-robot that
replicates the sensation of making love to a barely-legal Asian college
student majoring in microbiology? Asking for a friend.

You are too funny! "Asking for a friend"... lol

So are these really available??? Instead of microbiology, do they come in liberal arts majors? Asking for a friend...

--

Rick C.

- Get a 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209

 

On Monday, May 6, 2019 at 4:31:20 AM UTC-4, Martin Brown wrote:

On 06/05/2019 05:19, Flyguy wrote:
On Sunday, May 5, 2019 at 8:25:13 PM UTC-7, omni...@gmail.com wrote:
Hello electronics design experts. I will never fly a 737 Max. It is
so flawed that board members at Boeing, like Caroline Kennedy and
Nikki Haley (Trump UN ambassador) should use their expertise to
terminate that death trap.

Electronics design sometimes used redundant sensors in case it is
for life support. Not Boeing. Kennedy and Haley approve of

Weight and Balance of the 737 Max.

I looked at photos of 737 and 737 Max. The 737 has the front of the
engine at the front of the wing. The Max has the rear of the engine
at the front of the wing. That makes it stall easily. Software
cannot fix that weights and balance mistake.

Boeing is updating its software so the giant engines can unbalance
the airplane the same way as in the two crashes. Do you want to fly
a plane that only software is used to prevent stalling? Without
software it stalls. With software it is low cost. Nikki Haley is a
Trump liar. Do not fly Trump-Boeing death traps. Don doesn't.

The Board at Boeing is packed with dunces and insurance agents who
know nothing about Weights and Balances of aircraft.

Well, you should NEVER fly a 737 because you don't know what you are
talking about. The weight & balance of the 737 Max IS NOT the issue,
and never was. The issue has to do with MCAS (Maneuvering
Characteristics Augmentation System):
https://theaircurrent.com/aviation-safety/what-is-the-boeing-737-max-maneuvering-characteristics-augmentation-system-mcas-jt610/

The MCAS as delivered was deeply flawed and has been fixed; the
aircraft is now undergoing flight certification testing and will be
back in service shortly.


MCAS was the software *BODGE* installed to allow marketing to pretend
that the 737 Max was just another 737 model despite it having perverse
handling characteristics resulting from the physically larger engines
and a shifted centre of gravity. MCAS was badly flawed but something was
necessary to prevent the plane from stalling if flown like a real 737.

The only place the Max behaves differently is at extremely high levels of
attack, ones that a plane would only see in testing or very unusual,
abnormal flight.

MCAS as implemented would put the plane into a power dive to avoid
stalling if the AoA sensor went bad. A well trained aircrew might have
been able to counteract this although according to the last crash the
procedures do not work if take off is from a high altitude airport.

What exactly happened with the Ethiopian crash is unknown. For one
thing, the Ethiopians have been slow to release information, we still
haven't heard the voice recorder AFAIK, only some conclusions they are
trying to put forth from it. One interesting thing was that it was
the co-pilot that correctly identified that they had a runaway trim
condition and that they should turn off the electric trim. They did.
And then he apparently tried to trim it "manually", and indicated that
he could not. But, it's not clear what he meant by "manually" and there
is no more discussion. Did he mean using the wheels by hand? Or was he
confused and using the trim buttons on the wheel and calling that manual?
Then they turned the electric trim back on, at which point MCAS shoved the
nose back down again. The question here is can it be impossible to
turn the trim wheels? If so, then there is another serious problem.
In retrospect, the obvious best procedure would be
to first use the trim buttons to get the trim back to near neutral and
only then turn off the electric trim and trim manually. The Ethiopian
pilots had a lot less time to figure out what to do than Lion Air, where
they flew around for about 10 minutes. But still, after all the news about
LA, the new Boeing directive, you'd think they would have had plenty of
time to think about it, consider it, etc. So, maybe they did the right
thing and the trim wheel would not move. From the limited transcript
that the Ethiopians released, the communication back and forth between
the two pilots was poor. For example, had the co-pilot said, I'm
going to use the *trim wheel* or I can't move the trim wheel, then we'd
know what he was doing. Also, quite shocking that someone turned the
electric trim back on, without any discussion or informing the other
pilot. And how did MCAS then immediately push the nose down again?
Whoever turned it back on should have had their thumb on the trim UP
button, so that it would immediately move in the desired direction and
that would have overridden MCAS. At least that's how it's supposed to
be wired up and working.

Heads must roll in the FAA who signed this off on the nod without
properly checking that Boeing engineers had done the job right!

--
Regards,
Martin Brown

You would hope that would happen at both FAA and Boeing, including the CEO.
So far, his handling of this has been abysmal. It's shocking that such an
obviously flawed MCAS design could ever have been conceived of and built
at Boeing or any other aircraft manufacturer, for that matter.

 

On Sunday, May 5, 2019 at 11:25:13 PM UTC-4, omni...@gmail.com wrote:

Hello electronics design experts. I will never fly a 737 Max.
It is so flawed that board members at Boeing, like Caroline Kennedy and
Nikki Haley (Trump UN ambassador) should use their expertise to terminate
that death trap.

Electronics design sometimes used redundant sensors in case it is for
life support. Not Boeing. Kennedy and Haley approve of

Weight and Balance of the 737 Max.

I looked at photos of 737 and 737 Max. The 737 has the front of
the engine at the front of the wing. The Max has the rear of the engine at the front of the wing. That makes it stall easily.

It doesn't stall so easily. The problem only arises at very high levels
of angle of attack, that a plane would only experience in extreme, very
unusual situations. And then the problem is
that if you let go of the controls, instead of heading back toward a
lower angle of attack, the plane can nose up more, which would stall it.
The plane likely could not have been certified with that problem.
That's what MCAS was put in there to counteract. Granted it's not the
best design and a totally new plane design would have been better.
But then that costs a lot more, both in development and then you have
increased costs for the airlines due to training, type ratings, and now
you have a mixed fleet that adds to maintenance costs, etc.




Software cannot fix that

weights and balance mistake.

Boeing is updating its software so the giant engines can unbalance the
airplane the same way as in the two crashes. Do you want to fly a plane
that only software is used to prevent stalling? Without software it stalls.

That's not true, except at very high angles of attack it behaves just like
any other 737.

With software it is low cost.
Nikki Haley is a Trump liar. Do not fly Trump-Boeing death traps. Don doesn't.

The Board at Boeing is packed with dunces and insurance agents who know nothing
about Weights and Balances of aircraft.

And apparently you can add some pilots to that list, exactly how many,
no one knows. Because when the AOA failed, it presented itself as
runaway trim, which all pilots are trained to deal with. The Lion Air
flight, they flew around for about 10 mins and couldn't figure out
that the plane can't fly with the trim wildly oscillating back and forth
and that the procedure is to turn off the trim and set it MANUALLY.
The flight the say before, neither pilot there could figure it out,
by chance their happened to be another pilot in the jump seat and he
had to tell them what to do. The Ethiopian pilots screwed the pooch too.

Personally, I'm a lot more worried about incompetent pilots that don't
understand flight basics and that Boeing and the FAA were OK with a
very, very bad and obviously flawed MCAS system that relied on just
one AOA sensor. If they could do that, who knows what else is lurking.

 

[Jan Panteltje]

On a sunny day (Mon, 6 May 2019 06:27:34 -0700 (PDT)) it happened
trader4@optonline.net wrote in
<0f4b448b-5459-4dbd-8b22-ef2f484f8752@googlegroups.com>:

On Monday, May 6, 2019 at 3:28:36 AM UTC-4, Jan Panteltje wrote:
On a sunny day (Sun, 5 May 2019 23:13:13 -0700) it happened Banders
snap@mailchute.com> wrote in <qaoj9p$1jpn$1@gioia.aioe.org>:

On 05/05/2019 08:25 PM, omnilobe@gmail.com wrote:
Weight and Balance of the 737 Max.

I looked at photos of 737 and 737 Max. The 737 has the front of
the engine at the front of the wing. The Max has the rear of the engine at the front of the wing. That makes it stall
easily.
Actually, tail-heavy makes for an easy stall, and nose-heavy makes for a
dive. The crash planes weren't stalling, the AOA sensors just thought
they were. So you have it backward.

This photo should put your mind at ease.

https://www.colombotelegraph.com/wp-content/uploads/2019/03/Crash-Animation-of-Ethiopian-Airlines-flight-ET302-Boeing-737-Max-pl
ane.jpg

Normally software is tested and debugged, crashes happen,
bit of a nono to debug it in flights that carry people.

By all indications it was not a software bug,

I have read lately it was, it is anyways in the sense that it did not detect the output to ever tilt the thing more and more.
Looks like the dumbest loop you can ever write.
It did not check angular position (I think they added that now, only takes a 1$ MEMS chip),
and it had no redundancy.

from everything we've
seen the software did what the aerodynamic engineers and others spec'd
it to do. And it all was tested, including by test pilots, for
certification, including in extreme situations, where MCAS would be
involved. Apparently having a stuck AOA sensor wasn't part of the
testing.

My opinion is that such software should be written by pilots,
not by spaced out no flying experience people.

That's ridiculous and what evidence do you have that the software developers
were spaced out?

That it did what it did!!!

I have bluntly refused to write code for things that I could not use myself.

Well, thankfully we have plenty of others willing or we'd be screwed.

Yea, that is why so many of those IT projects are a disaster.

Boeing and Trump standing there 'selling' it when whe got elected...
Does anybody see the link?

No

CNN had it I think :-0

 

On Monday, May 6, 2019 at 5:37:12 AM UTC-4, Tom Gardner wrote:

On 06/05/19 10:00, Sylvia Else wrote:
On 6/05/2019 1:25 pm, omnilobe@gmail.com wrote:
Hello electronics design experts. I will never fly a 737 Max.
It is so flawed that board members at Boeing, like Caroline Kennedy and
Nikki Haley (Trump UN ambassador) should use their expertise to terminate
that death trap.

Electronics design sometimes used redundant sensors in case it is for
life support. Not Boeing. Kennedy and Haley approve of

Weight and Balance of the 737 Max.

I looked at photos of 737 and 737 Max. The 737 has the front of
the engine at the front of the wing. The Max has the rear of the engine at the
front of the wing. That makes it stall easily. Software cannot fix that
weights and balance mistake.

Boeing is updating its software so the giant engines can unbalance the
airplane the same way as in the two crashes. Do you want to fly a plane
that only software is used to prevent stalling? Without software it stalls.
With software it is low cost.
Nikki Haley is a Trump liar. Do not fly Trump-Boeing death traps. Don doesn't.

The Board at Boeing is packed with dunces and insurance agents who know nothing
about Weights and Balances of aircraft.


The effect of the software behaviour, as was, was to trim the aircraft forward
for no good reason.

The MCAS software commanded a dive for a very *good* reason:
the AoA was dangerously high. Or so it was being told by a
faulty sensor.


The pilots should have treated it as a runaway trim, and acted accordingly. Then
the crashes would not have occurred.

They were overridden by the MCAS.

Not true. The runaway trim procedure is to turn off the electric trim
and then trim manually. MCAS is disabled when the electric trim is off.
We have proof of that from the Lion Air flight on the day before the crash
that had the same problem. A pilot that happened to be riding in the
jump seat told the pilots who were flying what to do, because they could
not figure it out. And the cutout switches aren't in some obscure panel
somewhere, they are right next to the two trim wheels beside the pilots.
The trim wheels spin back and forth, noisely, and indicate the trim
position. If you saw the trim going to nose down, driven by something,
and the two clearly marked cutoff switches, what would you do? And
what to do is part of very basic flight training, it's the runaway trim
procedure.

Disabling the MCAS wasn't trivial.

Yes it was, per the above.



Normally manually

operating the controls will disable the autopilot and
give control back to the pilots. But MCAS wasn't part
of the autopilot and was designed to prevent that.

Don't forget that the *purpose* of MCAS was to *pretend*
nothing had changed, i.e. pretend that MCAS didn't exist!

You didn't have to know it was MCAS that was causing runaway trim.
It could have been an intermittent short, for example. A stuck
trim button would force it full nose down too.

It seems likely that Boeing expected that that would happen in the event that
this non-redundant computer system misbehaved.

Yet in both cases the pilots let the aircraft get itself seriously out of trim.
So much so, that in the case of the second crash, when the the pilots did
eventually disable the electric trim, the aircraft was so far out of trim that
the pilots were not strong enough to turn the trim wheels (or they didn't try -
it's rather unclear at the moment).

It was far more than "trim".

That is all that it was. MCAS just uses the electric trim to push the
nose down. You'd think that even without training at all, pilots would
realize that the plane isn't going to fly right with the electric trim
intermittently forcing extreme nose down. But that it will fly all day
long with just 4 deg trim and 70% power. Or that if the trim is somewhere
near neutral, then you can put enough force on the controls to make the
plane do what you want. So? Get the trim back to near neutral and TURN
IT OFF.

 

On Monday, May 6, 2019 at 5:44:18 AM UTC-4, Sylvia Else wrote:

On 6/05/2019 7:37 pm, Tom Gardner wrote:
On 06/05/19 10:00, Sylvia Else wrote:
On 6/05/2019 1:25 pm, omnilobe@gmail.com wrote:
Hello electronics design experts. I will never fly a 737 Max.
It is so flawed that board members at Boeing, like Caroline Kennedy and
Nikki Haley (Trump UN ambassador) should use their expertise to
terminate
that death trap.

Electronics design sometimes used redundant sensors in case it is for
life support. Not Boeing. Kennedy and Haley approve of

Weight and Balance of the 737 Max.

I looked at photos of 737 and 737 Max. The 737 has the front of
the engine at the front of the wing. The Max has the rear of the
engine at the front of the wing. That makes it stall easily. Software
cannot fix that
weights and balance mistake.

Boeing is updating its software so the giant engines can unbalance the
airplane the same way as in the two crashes. Do you want to fly a plane
that only software is used to prevent stalling? Without software it
stalls.
With software it is low cost.
Nikki Haley is a Trump liar. Do not fly Trump-Boeing death traps. Don
doesn't.

The Board at Boeing is packed with dunces and insurance agents who
know nothing
about Weights and Balances of aircraft.


The effect of the software behaviour, as was, was to trim the aircraft
forward for no good reason.

The MCAS software commanded a dive for a very *good* reason:
the AoA was dangerously high. Or so it was being told by a
faulty sensor.


The pilots should have treated it as a runaway trim, and acted
accordingly. Then the crashes would not have occurred.

They were overridden by the MCAS.

The procedure for a runaway trim involves tripping two switches that
disconnect the electric trim. It prevents the MCAS, or anything else,
from moving the trim electrically.

In the Ethopian crash, they did trip those switches, and it did prevent
the MCAS from doing anything, but they also couldn't, or didn't, rotate
the trim wheels manually to get the aircraft back into trim. They then,
unaccountably, tripped the switches again, reenabling the electric trim,
and in the process letting the MCAS make the situation even worse.

Sylvia.

+++++1

And we know that following the runaway trim procedure works, because that's
what they did on the Lion Air flight the day before the crash. The
passenger pilot in the jump seat had to tell the two flying to do it.
They did, the flight went on to it's destination.

The cavalier way that was treated is something else that should be looked
at and corrected. IDK what procedures any airline has, but you would think
that after a plane experienced a severe event like this, the crews that
are taking it out subsequently, especially the very next flight, would be
informed about the abnormal behavior and what was needed to correct it.
What the maintenance crew did with the AOA or whatever else still isn't
public. Nor is the root cause of what was wrong with AOAs in two brand
new planes? You'd think they would suspect something, eg a manufacturing
defect or incorrect installation and there would have been a directive
to inspect, replace all similar AOA. But nothing, very weird.

 

On Monday, May 6, 2019 at 5:37:31 AM UTC-4, Jan Panteltje wrote:

On a sunny day (Mon, 6 May 2019 19:00:05 +1000) it happened Sylvia Else
sylvia@email.invalid> wrote in <gjabcoF495jU1@mid.individual.net>:

The effect of the software behaviour, as was, was to trim the aircraft
forward for no good reason.

The pilots should have treated it as a runaway trim, and acted
accordingly. Then the crashes would not have occurred.

The system could not be turned off AFAIK.

Incorrect. There are two clearly marked cutoff switches for the electric
trim, located right at the large trim wheels that are spinning back and
forth beside the pilots. Turned off, MCAS can't do anything.

It seems likely that Boeing expected that that would happen in the event
that this non-redundant computer system misbehaved.

Yet in both cases the pilots let the aircraft get itself seriously out
of trim. So much so, that in the case of the second crash, when the the
pilots did eventually disable the electric trim, the aircraft was so far
out of trim that the pilots were not strong enough to turn the trim
wheels (or they didn't try - it's rather unclear at the moment).


Have not read all the details, but it seemed they increased speed / engine thrust to prevent a stall.
What th3 stupid system should do it check for altitude and a lot more parameters before doing the fatal trim.

Altitude would not seem to be a parameter in determining if the plane is
stalling or not.

Where I live in the old days pilot training to get out of a stall was on a little 'Tiger Moth',
little bi-planes:
https://en.wikipedia.org/wiki/De_Havilland_Tiger_Moth
They used to do that next to our house, above the neighbors land .....
Training, yes, and it did not always go smooth.



Serious questions need to be asked about the competence of the pilots.

No, that is Boeing PR shit.

Wrong. A pilot on the Lion Air flight with the same problem the day before
the crash followed the correct procedure. But he was in the jump seat,
not flying. The two flying pilots couldn't figure it out. He told them
the procedure, it worked, the plane flew on to it's destination.

You can get abnormal trim from a short or similar component failure.
That's why those cutoff switches and manual trim wheels are in all
aircraft, not just the Max.

That plane is a disaster, it is unstable by its nature.
Pilots were not even informed of that system.
Try reading a 'manual' (having severe deficiencies in it) in the 60 seconds or so you have before the crash.

I agree it should have been in the manual. But even there, pilots disagree.
After the LA crash, the head of United pilot's union said they were OK
with it not being in the manual, that they don't need to know that level
of the inner workings. I found that quite stunning, but that's what he said.
And we have the Ethiopian crash, in which case those pilots knew about the
system and how it worked and it didn't matter. No searching in manuals was
required. The runaway trim procedure is very basic and is one of the
memory items all competent pilots are supposed to understand.

 

[Joe Chisolm]

On Mon, 06 May 2019 08:12:13 +0000, DecadentLinuxUserNumeroUno wrote:

omnilobe@gmail.com wrote in
news:c53fb380-eaac-4408-9422-959a9d1f8d3f@googlegroups.com:

Boeing is updating its software so the giant engines can unbalance the
airplane the same way as in the two crashes. Do you want to fly a plane
that only software is used to prevent stalling? Without software it
stalls.

The software was for IF the plane stalled, which it did not. It was
a sensor error.

It is because the pilot does not always have a sense of a stall
situation, which the craft never get into anyway unless the pilot and
copilot are sleeping.

A stalling plane is pilot error, not airplane error.

The biggest issue to me is that there was no release switch to return
pilot control.

There is a procedure and it's a MEMORY item of what to do in a
run-away trim situation. There are 2 switches, just below the
throttle quadrant that cuts out the electric trim (and MCAS).
Once turned off the AFM says you do not turn it back on. It
stays off until you land.
Auto Pilot off
Auto Throttles off
Auto trim off.

A friend of mine with over 10K hours in the 737 variants explains
these are memory items drilled into your head and you practice
them every 6 months in the simulator check ride.

In the Ethiopian crash it seems they never disabled the auto throttles
and towards the end they re-engaged auto trim (and MCAS). The aircraft
was already red-line in speed.

--
Chisolm
Republic of Texas

 

On Monday, May 6, 2019 at 5:00:14 AM UTC-4, Sylvia Else wrote:

On 6/05/2019 1:25 pm, omnilobe@gmail.com wrote:
Hello electronics design experts. I will never fly a 737 Max.
It is so flawed that board members at Boeing, like Caroline Kennedy and
Nikki Haley (Trump UN ambassador) should use their expertise to terminate
that death trap.

Electronics design sometimes used redundant sensors in case it is for
life support. Not Boeing. Kennedy and Haley approve of

Weight and Balance of the 737 Max.

I looked at photos of 737 and 737 Max. The 737 has the front of
the engine at the front of the wing. The Max has the rear of the engine at the front of the wing. That makes it stall easily. Software cannot fix that
weights and balance mistake.

Boeing is updating its software so the giant engines can unbalance the
airplane the same way as in the two crashes. Do you want to fly a plane
that only software is used to prevent stalling? Without software it stalls.
With software it is low cost.
Nikki Haley is a Trump liar. Do not fly Trump-Boeing death traps. Don doesn't.

The Board at Boeing is packed with dunces and insurance agents who know nothing
about Weights and Balances of aircraft.


The effect of the software behaviour, as was, was to trim the aircraft
forward for no good reason.

The pilots should have treated it as a runaway trim, and acted
accordingly. Then the crashes would not have occurred.

+1

And the Lion Air pilot on the flight the day before the crash, did exactly
that. He wasn't flying, just catching a rid in the jump seat. When the
other pilots couldn't figure it out, he did. This is the most shocking
thing. This isn't rocket science and the LA pilots on the fatal crash
had ~10 mins to figure it out. Let's see, the plane is porpoising around,
driven DOWN by something, then corrected back up by you with the trim
buttons. The trim wheels by your seat are noisely spinning back and
forth, the indicators showing extreme down and up trim. Hello? You should
know that the planes you've flown so many times before, the trim needs to
be near neutral. So, get it there and turn off the electric! Trim
manually. It's part of basic flight training. In fact one of the things
pilots are supposed to have committed to memory is that if all is going
screwy, set power to 70%, trim to 3 deg up and the plane will fly.

It seems likely that Boeing expected that that would happen in the event
that this non-redundant computer system misbehaved.

Yes.

Yet in both cases the pilots let the aircraft get itself seriously out
of trim. So much so, that in the case of the second crash, when the the
pilots did eventually disable the electric trim, the aircraft was so far
out of trim that the pilots were not strong enough to turn the trim
wheels (or they didn't try - it's rather unclear at the moment).

Agree. We really don't know from what limited info the Ethiopians have
released. The co-pilot turned off the electric and said that he was
trying to trim manually, but could not. But it's not clear if he meant
he was trying to turn the wheel or if he meant he was using the button
on the controls. It would seem most likely that he was trying to turn
the wheel, but could not. If so, that would be another huge problem,
one that could extend to all 737s. Is it possible with extreme trim
and enough airspeed that you can't turn the wheel? IDK, that seems
unlikely, because then any runaway trim could be fatal. Also, someone
then turned the electric back on. That would be consistent with not being
able to move it by hand, but then you should have the trim UP button
pressed on the controls as you turn it back on, get the trim to near
neutral, then turn it off again. Instead after it was turned on MCAS
was allowed to push it nose down again, this time into the dirt.

Serious questions need to be asked about the competence of the pilots.
Would a properly trained crew have had any difficulties, even in the
absence of details about MCAS? I rather think not.

Sylvia.

I agree. Especially in the case of the LA crash. They had ~10 mins of
flying time to figure it out. And they did plenty else wrong too, like
keeping the airspeed high, which would just make trying to trim it
harder. Also, all the trouble started just as they retracted the flaps.
You'd think a last ditch idea might be to try putting the flaps out?
That would have disabled MCAS. Still, another question is if this is
really a training issue? It's quite possible that they were trained
a lot but screwed up anyway. And part of this is so very basic.
A plane isn't going to fly right when something is pushing the trim nose
down. It flies nice when trim is near neutral. Seems pretty obvious
what to do, but maybe in a real crisis, people can't correctly react?
That LA pilot had handed over control to the co-pilot as he was flipping
through the manuals. Where you'd expect to find a page that covers
that problem, IDK. He'd have been better off focusing on very basic
flight principles.

 

On Monday, May 6, 2019 at 4:12:17 AM UTC-4, DecadentLinux...@decadence.org wrote:

omnilobe@gmail.com wrote in
news:c53fb380-eaac-4408-9422-959a9d1f8d3f@googlegroups.com:

Boeing is updating its software so the giant engines can unbalance
the airplane the same way as in the two crashes. Do you want to
fly a plane that only software is used to prevent stalling?
Without software it stalls.

The software was for IF the plane stalled, which it did not. It was
a sensor error.

It is because the pilot does not always have a sense of a stall
situation, which the craft never get into anyway unless the pilot and
copilot are sleeping.

That's incorrect. The pilots know that a stall is approaching with the
STICK SHAKER and audible alerts.

A stalling plane is pilot error, not airplane error.

The issue with the 737 Max is that at high levels of AOA, the plane has
a tendency to nose up even further. Part of the certification process
is that if you release the controls the plane is supposed to head in
a stable direction, not toward instability. That is why MCAS was added.

The biggest issue to me is that there was no release switch to return
pilot control.

Wrong again, as proven by the first Lion Air flight that had the same problem
the day before the crash. The pilot in the jump seat, who was not one of the
crew, correctly identified the runaway trim problem, told the two pilots
flying what to do. They turned off the electric trim, used manual trim
and the plane flew on to it's destination.

Wrong, always wrong.

 

On Monday, May 6, 2019 at 5:00:14 AM UTC-4, Sylvia Else wrote:

On 6/05/2019 1:25 pm, omnilobe@gmail.com wrote:
Hello electronics design experts. I will never fly a 737 Max.
It is so flawed that board members at Boeing, like Caroline Kennedy and
Nikki Haley (Trump UN ambassador) should use their expertise to terminate
that death trap.

Electronics design sometimes used redundant sensors in case it is for
life support. Not Boeing. Kennedy and Haley approve of

Weight and Balance of the 737 Max.

I looked at photos of 737 and 737 Max. The 737 has the front of
the engine at the front of the wing. The Max has the rear of the engine at the front of the wing. That makes it stall easily. Software cannot fix that
weights and balance mistake.

Boeing is updating its software so the giant engines can unbalance the
airplane the same way as in the two crashes. Do you want to fly a plane
that only software is used to prevent stalling? Without software it stalls.
With software it is low cost.
Nikki Haley is a Trump liar. Do not fly Trump-Boeing death traps. Don doesn't.

The Board at Boeing is packed with dunces and insurance agents who know nothing
about Weights and Balances of aircraft.


The effect of the software behaviour, as was, was to trim the aircraft
forward for no good reason.

The pilots should have treated it as a runaway trim, and acted
accordingly. Then the crashes would not have occurred.

I have not seen anything clear or athoritative, but it appears the situation is not so simple to diagnose as was initially indicated. When you have a cockpit full of instruments and controls and "something" is wrong and the plane is behaving very erratically, it seems not so simple to do the right thing and know that it was right in the face of the airplane continuing to fly improperly.

It seems likely that Boeing expected that that would happen in the event
that this non-redundant computer system misbehaved.

Yet in both cases the pilots let the aircraft get itself seriously out
of trim. So much so, that in the case of the second crash, when the the
pilots did eventually disable the electric trim, the aircraft was so far
out of trim that the pilots were not strong enough to turn the trim
wheels (or they didn't try - it's rather unclear at the moment).

There is the main point. It is too early to be making judgements. I like that some consider the problem to be software failures that could have been prevented by using pilots to write code. lol

Serious questions need to be asked about the competence of the pilots.
Would a properly trained crew have had any difficulties, even in the
absence of details about MCAS? I rather think not.

Serious questions need to be asked about the process that allowed this system go so wrong that so many people died in two accidents. This investigation should be no less rigorous than the investigation into the Challenger accident.

--

Rick C.

-- Get a 1,000 miles of free Supercharging
-- Tesla referral code - https://ts.la/richard11209

 

[bitrex]

On 5/6/19 4:26 AM, DecadentLinuxUserNumeroUno@decadence.org wrote:

bitrex <user@example.net> wrote in news:c1RzE.535275$cD4.504076
@fx43.iad:

500-something people dead and Boeing seems to just shrug it off like
they're Microsoft and they're gonna patch a bug in Windows 10 at the
next update. "Sorry, our bad."

You are so full of shit. You have no clue what they are doing with
the families of the victims, etc.

I'd imagine they're hiring a lot more of the best legal teams money can
buy to fight all the negligence lawsuits heading their way and tie them
up in court until about the year 2045 would be my guess.

You are the worst kind of speculator.

When Boeing's execs heard an Ethiopian plane had crashed they were like
"wtf? what are those monkeys doing running an airline with our planes,
anyway? Well we'll just patiently explain to low IQ Americans that the
reason it crashed is due to the even lower IQ of Africans. and well I
guess we gotta pay something what's a good payout for a shithole country
victim, like $25?"

 

[John Larkin]

On Sun, 5 May 2019 20:25:09 -0700 (PDT), omnilobe@gmail.com wrote:

Hello electronics design experts. I will never fly a 737 Max.
It is so flawed that board members at Boeing, like Caroline Kennedy and
Nikki Haley (Trump UN ambassador) should use their expertise to terminate
that death trap.

Electronics design sometimes used redundant sensors in case it is for
life support. Not Boeing. Kennedy and Haley approve of

Weight and Balance of the 737 Max.

I looked at photos of 737 and 737 Max. The 737 has the front of
the engine at the front of the wing. The Max has the rear of the engine at the front of the wing. That makes it stall easily. Software cannot fix that
weights and balance mistake.

Boeing is updating its software so the giant engines can unbalance the
airplane the same way as in the two crashes. Do you want to fly a plane
that only software is used to prevent stalling?

A jet plane is full of software that's critical to flight. The
throttles aren't mechanical any more, they send signals to the FADECs.
And on and on.

I don't think that your "looking at photos" is solid aerodynamic
analysis.

Boeing made some appalling choices with the AOA sensors. Absent those
mistakes, the 737 would be fine.

The Board of Directors didn't design the anti-stall system or decide
to only use one AOA sensor per flight.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[bitrex]

On 5/6/19 9:27 AM, trader4@optonline.net wrote:

On Monday, May 6, 2019 at 3:28:36 AM UTC-4, Jan Panteltje wrote:
On a sunny day (Sun, 5 May 2019 23:13:13 -0700) it happened Banders
snap@mailchute.com> wrote in <qaoj9p$1jpn$1@gioia.aioe.org>:

On 05/05/2019 08:25 PM, omnilobe@gmail.com wrote:
Weight and Balance of the 737 Max.

I looked at photos of 737 and 737 Max. The 737 has the front of
the engine at the front of the wing. The Max has the rear of the engine at the front of the wing. That makes it stall easily.
Actually, tail-heavy makes for an easy stall, and nose-heavy makes for a
dive. The crash planes weren't stalling, the AOA sensors just thought
they were. So you have it backward.

This photo should put your mind at ease.
https://www.colombotelegraph.com/wp-content/uploads/2019/03/Crash-Animation-of-Ethiopian-Airlines-flight-ET302-Boeing-737-Max-pl
ane.jpg

Normally software is tested and debugged, crashes happen,
bit of a nono to debug it in flights that carry people.

By all indications it was not a software bug, from everything we've
seen the software did what the aerodynamic engineers and others spec'd
it to do. And it all was tested, including by test pilots, for
certification, including in extreme situations, where MCAS would be
involved.

After all the fatal crashes that have happened in recent history due to
fucked up/iced-up/taped-over airflow sensors they go and build in
another system that automatically points the plane at the ground if the
one fuckin' tube that the software relies on gets fucked up, as they
always seem to.

Apparently having a stuck AOA sensor wasn't part of the
testing.

Not testing the edge-cases of your software, if that's indeed what they
didn't do, falls under "software bug." Just like you can build a power
amplifier that oscillates like mad at ultrasonic frequency until it
burns itself straight out when its input is removed that is a design
error, not a user error as inputs being removed is a natural thing to
happen to amplifiers, which often happens.

Gee whiz, I'm no aviation engineer but I probably could've thought to
test that scenario. Did they fire anyone? Are they hiring, now? That's
what I'll put on my resume "Yeah I'm an engineer from a totally
different field but I probably coulda thought to test that."

 

[bitrex]

On 5/6/19 9:16 AM, gnuarm.deletethisbit@gmail.com wrote:

On Monday, May 6, 2019 at 3:52:38 AM UTC-4, bitrex wrote:
On 5/6/19 3:28 AM, Jan Panteltje wrote:
On a sunny day (Sun, 5 May 2019 23:13:13 -0700) it happened Banders
snap@mailchute.com> wrote in <qaoj9p$1jpn$1@gioia.aioe.org>:

On 05/05/2019 08:25 PM, omnilobe@gmail.com wrote:
Weight and Balance of the 737 Max.

I looked at photos of 737 and 737 Max. The 737 has the front of
the engine at the front of the wing. The Max has the rear of the engine at the front of the wing. That makes it stall easily.
Actually, tail-heavy makes for an easy stall, and nose-heavy makes for a
dive. The crash planes weren't stalling, the AOA sensors just thought
they were. So you have it backward.

This photo should put your mind at ease.
https://www.colombotelegraph.com/wp-content/uploads/2019/03/Crash-Animation-of-Ethiopian-Airlines-flight-ET302-Boeing-737-Max-pl
ane.jpg

Normally software is tested and debugged, crashes happen,
bit of a nono to debug it in flights that carry people.

My opinion is that such software should be written by pilots,
not by spaced out no flying experience people.

I have bluntly refused to write code for things that I could not use myself.

Ever write the code for an artificially intelligent sex-robot that
replicates the sensation of making love to a barely-legal Asian college
student majoring in microbiology? Asking for a friend.

You are too funny! "Asking for a friend"... lol

So are these really available??? Instead of microbiology, do they come in liberal arts majors? Asking for a friend...

I don't honestly know what a robot needs to go to college for I imagine
they could just upload all the data in like a microsecond.

Maybe it's just for personality/backstory reasons. Anyway I went to a
liberal arts college and ah just some friendly advice probably best to
take your chances with the science-student model.

Very small, minor bug with early liberal arts model which results in
occasionally she breaks down your bedroom door with a fire ax at 3 am
while asking through sobs if you truly love her even tho she is not a
"real girl" YOU DON'T REALLY LOVE ME!!! I would suggest you affirm that
you do to the robot-girl with the fire axe if you encounter this
definitely-uncommon bug.

 

[bitrex]

On 5/6/19 9:42 AM, Jan Panteltje wrote:

On a sunny day (Mon, 6 May 2019 06:27:34 -0700 (PDT)) it happened
trader4@optonline.net wrote in
0f4b448b-5459-4dbd-8b22-ef2f484f8752@googlegroups.com>:

On Monday, May 6, 2019 at 3:28:36 AM UTC-4, Jan Panteltje wrote:
On a sunny day (Sun, 5 May 2019 23:13:13 -0700) it happened Banders
snap@mailchute.com> wrote in <qaoj9p$1jpn$1@gioia.aioe.org>:

On 05/05/2019 08:25 PM, omnilobe@gmail.com wrote:
Weight and Balance of the 737 Max.

My opinion is that such software should be written by pilots,
not by spaced out no flying experience people.

That's ridiculous and what evidence do you have that the software developers
were spaced out?

That it did what it did!!!

When you design a safety system that relies on a single sensor to
determine whether the aircraft system is in a safety-critical state that
needs action "the AOA sensor indicates the aircraft is in stall", how do
you distinguish between a "normal" safety-critical situation "the AOA
sensor indicates the aircraft is in stall" where the plane a a whole is
in an error state but the safety system itself is still functioning
normally, vs. "the AOA indicates the aircraft is in stall...because the
AOA sensor is trashed" where the plane is still functioning normally but
the safety system is in an error state.

I don't know that I have an answer to that question either other than
"don't do that."

 

[Jan Panteltje]

On a sunny day (Mon, 6 May 2019 07:26:28 -0700 (PDT)) it happened
trader4@optonline.net wrote in
<bc496342-1823-4eb9-9b07-ab96aae6321f@googlegroups.com>:

On Monday, May 6, 2019 at 5:37:31 AM UTC-4, Jan Panteltje wrote:
On a sunny day (Mon, 6 May 2019 19:00:05 +1000) it happened Sylvia Else
sylvia@email.invalid> wrote in <gjabcoF495jU1@mid.individual.net>:

The effect of the software behaviour, as was, was to trim the aircraft
forward for no good reason.

The pilots should have treated it as a runaway trim, and acted
accordingly. Then the crashes would not have occurred.

Yes I did read that.

The system could not be turned off AFAIK.


Incorrect. There are two clearly marked cutoff switches for the electric
trim, located right at the large trim wheels that are spinning back and
forth beside the pilots. Turned off, MCAS can't do anything.

If that is so then it is indeed strange the pilots did not use those.
Maybe it had to do with too much flying on auto-pilot and not enough real flight hours,
too much relying on automation, much has been written about that.

It seems likely that Boeing expected that that would happen in the event
that this non-redundant computer system misbehaved.

Yet in both cases the pilots let the aircraft get itself seriously out
of trim. So much so, that in the case of the second crash, when the the
pilots did eventually disable the electric trim, the aircraft was so far
out of trim that the pilots were not strong enough to turn the trim
wheels (or they didn't try - it's rather unclear at the moment).


Have not read all the details, but it seemed they increased speed / engine thrust to prevent a stall.
What th3 stupid system should do it check for altitude and a lot more parameters before doing the fatal trim.

Altitude would not seem to be a parameter in determining if the plane is
stalling or not.

You can only get out of a stall by putting the nose down gaining speed if you have any altitude at all.
So it the very low altitude situation the system should not interfere in my view (minimum altitude can be calculated I'd think),
but simply sound a warning.
It is a bit tricky, you can argue that is just where I need that system.

Where I live in the old days pilot training to get out of a stall was on a little 'Tiger Moth',
little bi-planes:
https://en.wikipedia.org/wiki/De_Havilland_Tiger_Moth
They used to do that next to our house, above the neighbors land .....
Training, yes, and it did not always go smooth.



Serious questions need to be asked about the competence of the pilots.

No, that is Boeing PR shit.

Wrong. A pilot on the Lion Air flight with the same problem the day before
the crash followed the correct procedure. But he was in the jump seat,
not flying. The two flying pilots couldn't figure it out. He told them
the procedure, it worked, the plane flew on to it's destination.

You can get abnormal trim from a short or similar component failure.
That's why those cutoff switches and manual trim wheels are in all
aircraft, not just the Max.

PR shit because Boeing did not even inform the pilots of the system it seems,
and is trying to avoid large damage claims.
All the grounded airlines all over the world that now have less income can sue Boeing.
That could go into the very high numbers of dollars.

That plane is a disaster, it is unstable by its nature.
Pilots were not even informed of that system.
Try reading a 'manual' (having severe deficiencies in it) in the 60 seconds or so you have before the crash.


I agree it should have been in the manual. But even there, pilots disagree.
After the LA crash, the head of United pilot's union said they were OK
with it not being in the manual, that they don't need to know that level
of the inner workings. I found that quite stunning, but that's what he said.
And we have the Ethiopian crash, in which case those pilots knew about the
system and how it worked and it didn't matter. No searching in manuals was
required. The runaway trim procedure is very basic and is one of the
memory items all competent pilots are supposed to understand.

I would not want to fly a plane without knowing what control systems it has.
That is a bit tricky too, does a truck driver need to know how ABS works etc...
or how the fuel injection computer works?
If you say 'no' then having no redundancy is a crime?

 

On Monday, May 6, 2019 at 12:09:51 PM UTC-4, bitrex wrote:

On 5/6/19 10:36 AM, Joe Chisolm wrote:
On Mon, 06 May 2019 08:12:13 +0000, DecadentLinuxUserNumeroUno wrote:

omnilobe@gmail.com wrote in
news:c53fb380-eaac-4408-9422-959a9d1f8d3f@googlegroups.com:

Boeing is updating its software so the giant engines can unbalance the
airplane the same way as in the two crashes. Do you want to fly a plane
that only software is used to prevent stalling? Without software it
stalls.

The software was for IF the plane stalled, which it did not. It was
a sensor error.

It is because the pilot does not always have a sense of a stall
situation, which the craft never get into anyway unless the pilot and
copilot are sleeping.

A stalling plane is pilot error, not airplane error.

The biggest issue to me is that there was no release switch to return
pilot control.

There is a procedure and it's a MEMORY item of what to do in a
run-away trim situation. There are 2 switches, just below the
throttle quadrant that cuts out the electric trim (and MCAS).
Once turned off the AFM says you do not turn it back on. It
stays off until you land.
Auto Pilot off
Auto Throttles off
Auto trim off.

A friend of mine with over 10K hours in the 737 variants explains
these are memory items drilled into your head and you practice
them every 6 months in the simulator check ride.

In the Ethiopian crash it seems they never disabled the auto throttles
and towards the end they re-engaged auto trim (and MCAS). The aircraft
was already red-line in speed.


Boeing knows from a PR perspective that many Americans will be glad to
accept that it was the dumb filthy subhuman shithole country pilots who
caused the crash to happen and they very much hoped to roll with that
explanation if it was just one, except there were two crashes in
entirely different shithole countries with entirely different crews, to
explain.

IDK what version of reality you're watching, but the first crash was
Lion Air in Indonesia and from that moment on, the focus has been almost
exclusively on the plane, the poor MCAS design and not the pilots.
Which is wrong, because there should be focus on both. We need to
understand why pilots can't identify a very basic thing, runaway trim
and follow the procedure. It's supposed to be a memory item.
There are multiple parties to blame here:

Boeing bad MCAS design
FAA approving it
FAA never informed that the authority of MCAS had been greatly increased
Pilots incapable of identifying and dealing with runaway trim.

It's hard to understand how pilots could watch the electric
trim run the plane nose down, time and time again, with the trim wheels
beside them spinning, showing abnormal trim down, followed by trim up
when you corrected it via the trim buttons. Hello? Get it near
neutral, where you know it belongs, turn off the electric to stop
whatever is causing it to move, and trim manually. In the LA crash
they had almost 10 mins to figure it out. The Ethiopians had much
less time, but then they also knew about MCAS and the previous crash.