Fresh setback for Boeing's 737 MAX

[Cursitor Doom]

Similar fault to last time found in software:


https://tinyurl.com/y4dcqwnb



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[Rick C]

On Wednesday, June 26, 2019 at 7:27:32 PM UTC-4, Cursitor Doom wrote:

Similar fault to last time found in software:


https://tinyurl.com/y4dcqwnb

Here is the link for the actual report rather than having to read the ZeroHedge interpretation.

https://www.cnn.com/2019/06/26/politics/boeing-737-max-flaw/index.html

--

Rick C.

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

 

[Cursitor Doom]

On Wed, 26 Jun 2019 16:42:36 -0700, Rick C wrote:

On Wednesday, June 26, 2019 at 7:27:32 PM UTC-4, Cursitor Doom wrote:
Similar fault to last time found in software:


https://tinyurl.com/y4dcqwnb

Here is the link for the actual report rather than having to read the
ZeroHedge interpretation.

https://www.cnn.com/2019/06/26/politics/boeing-737-max-flaw/index.html

Ah, so CNN is pure news with no <cough> "interpretation" then. Nice to
know.
;->



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This message may be freely reproduced without limit or charge only via
the Usenet protocol. Reproduction in whole or part through other
protocols, whether for profit or not, is conditional upon a charge of
GBP10.00 per reproduction. Publication in this manner via non-Usenet
protocols constitutes acceptance of this condition.

 

[Bill Sloman]

On Friday, June 28, 2019 at 9:27:18 PM UTC+2, Cursitor Doom wrote:

On Wed, 26 Jun 2019 16:42:36 -0700, Rick C wrote:

On Wednesday, June 26, 2019 at 7:27:32 PM UTC-4, Cursitor Doom wrote:
Similar fault to last time found in software:


https://tinyurl.com/y4dcqwnb

Here is the link for the actual report rather than having to read the
ZeroHedge interpretation.

https://www.cnn.com/2019/06/26/politics/boeing-737-max-flaw/index.html

Ah, so CNN is pure news with no <cough> "interpretation" then. Nice to
know.
;-

It does lack the kind of "interpretation" that rabid right wingers expect to get with their daily dose of propaganda, but services like CNN do present stuff in a way the main stream of the population finds acceptable.

That how the free market works. CNN is primarily serving an American audience, so their slant is slightly more right wing than the British BBC or the Australian ABC, but it isn't a gross difference, and you have to look hard to find an example of a perceptible difference.

--
Bill Sloman, Sydney

 

Bill Sloman <bill.sloman@ieee.org> wrote in
news:8105193b-33ee-4d19-b8b6-d885395c0735@googlegroups.com:

On Friday, June 28, 2019 at 9:27:18 PM UTC+2, Cursitor Doom wrote:
On Wed, 26 Jun 2019 16:42:36 -0700, Rick C wrote:

On Wednesday, June 26, 2019 at 7:27:32 PM UTC-4, Cursitor Doom
wrote:
Similar fault to last time found in software:


https://tinyurl.com/y4dcqwnb

Here is the link for the actual report rather than having to
read the ZeroHedge interpretation.

https://www.cnn.com/2019/06/26/politics/boeing-737-max-
flaw/inde
x.html

Ah, so CNN is pure news with no <cough> "interpretation" then.
Nice to know.
;-

It does lack the kind of "interpretation" that rabid right wingers
expect to get with their daily dose of propaganda, but services
like CNN do present stuff in a way the main stream of the
population finds acceptable.

That how the free market works. CNN is primarily serving an
American audience, so their slant is slightly more right wing than
the British BBC or the Australian ABC, but it isn't a gross
difference, and you have to look hard to find an example of a
perceptible difference.

One of the few things I find to be a gain in the crapstorm DJT has
caused is that it makes it easier to spot the extreme idiots as they
come out of the woodwork with their "fake news" declarations.

I have never seen a more immature bunch of sheep.

I strive for whirled peas.

 

[Winfield Hill]

Bill Sloman wrote...
>

CNN's article is also grossly-defective I'd say.
They talk about a microprocessor failure, when in
fact the issue is the microprocessor's software.
The complaint is pushing the button on the yoke
doesn't make a fast enough elevator-trim change.
And by fast, we're talking a few seconds. That's
easily fixed in the program, if everyone agrees.


--
Thanks,
- Win

 

Winfield Hill <winfieldhill@yahoo.com> wrote in
news:qf816d01roq@drn.newsguy.com:

Bill Sloman wrote...


CNN's article is also grossly-defective I'd say.
They talk about a microprocessor failure, when in
fact the issue is the microprocessor's software.

They reported what they got off of the AP newswire surely. I
heard that too, and knew what they really meant.

The complaint is pushing the button on the yoke
doesn't make a fast enough elevator-trim change.
And by fast, we're talking a few seconds. That's
easily fixed in the program, if everyone agrees.

Yeah... I want an overide lever/motors somewhere so that hand
cranking dials is not ever needed. Or if they can guarantee the
dials are crankable in the mechanical aspect of the design, then add
cockpit motors to do it (fast) in a fail mode, and if those then
fail, THEN the hand cranks get used.

 

On Sunday, June 30, 2019 at 3:39:56 AM UTC-4, DecadentLinux...@decadence.org wrote:

Winfield Hill <winfieldhill@yahoo.com> wrote in
news:qf816d01roq@drn.newsguy.com:

Bill Sloman wrote...


CNN's article is also grossly-defective I'd say.
They talk about a microprocessor failure, when in
fact the issue is the microprocessor's software.

They reported what they got off of the AP newswire surely. I
heard that too, and knew what they really meant.


The complaint is pushing the button on the yoke
doesn't make a fast enough elevator-trim change.
And by fast, we're talking a few seconds. That's
easily fixed in the program, if everyone agrees.

Yeah... I want an overide lever/motors somewhere so that hand
cranking dials is not ever needed. Or if they can guarantee the
dials are crankable in the mechanical aspect of the design, then add
cockpit motors to do it (fast) in a fail mode, and if those then
fail, THEN the hand cranks get used.

And then factor in the added failure modes and possible scenarios
introduced by all that additional complexity.
Perhaps you can point us to all the accident reports over the last half
century from runaway trim where the pilots followed the correct procedure
but were unable to correct it in time? So far, I know of only one case
where that *might* have happened, that's the crash in Ethiopia of the
737 Max. And that's already been addressed to a large extent, by
limiting how much MCAS can nose down the plane and for how long and
by disabling it if the AOA sensors disagree.

 

Too bad Boeing was not serious after crash #1. They may have been able to have a mea culpa and somewhat gracefully fix the problem.

 

On Sunday, June 30, 2019 at 1:52:19 PM UTC-4, DecadentLinuxUserNumeroUno wrote:

trader4@optonline.net wrote in news:d8a03c6e-8f6f-4862-a0e1-
4af302ecf43b@googlegroups.com:

And then factor in the added failure modes and possible scenarios
introduced by all that additional complexity.

Nope. Just a motor to crank the cockpit dials. That leaves all the
original mechanicals in place, which is the stuff that WAS engineered
properly.

IDK how you can say it was engineered properly when if the trim
runs away signifcantly, puts the plane into a steep dive that increases
the necessary force, a pilot doesn't have enough strength to overcome it.
What's interesting is that apparently it hasn't been a problem in the
last half century, where trim ran away to that extent, until now.

And if that fails, the pilot and co are right there to perform the
tried and true.

Do not over complicate it.

 

[DecadentLinuxUserNumeroUn]

trader4@optonline.net wrote in news:d8a03c6e-8f6f-4862-a0e1-
4af302ecf43b@googlegroups.com:

And then factor in the added failure modes and possible scenarios
introduced by all that additional complexity.

Nope. Just a motor to crank the cockpit dials. That leaves all the
original mechanicals in place, which is the stuff that WAS engineered
properly.

And if that fails, the pilot and co are right there to perform the
tried and true.

Do not over complicate it.

 

[Gunther Heiko Hagen]

On Sun, 30 Jun 2019 11:20:16 -0700, trader4 wrote:

IDK how you can say it was engineered properly when if the trim runs
away signifcantly, puts the plane into a steep dive that increases the
necessary force, a pilot doesn't have enough strength to overcome it.
What's interesting is that apparently it hasn't been a problem in the
last half century, where trim ran away to that extent, until now.

They need to fix it fast before it attracts the "flying coffin" tag.

 

[DLUNU]

trader4@optonline.net wrote in
news:d07712b8-5854-48b8-9b9e-fb4d56aedd86@googlegroups.com:

On Sunday, June 30, 2019 at 1:52:19 PM UTC-4,
DecadentLinuxUserNumeroUno wrote:
trader4@optonline.net wrote in news:d8a03c6e-8f6f-4862-a0e1-
4af302ecf43b@googlegroups.com:

And then factor in the added failure modes and possible
scenarios introduced by all that additional complexity.

Nope. Just a motor to crank the cockpit dials. That leaves all
the
original mechanicals in place, which is the stuff that WAS
engineered properly.

IDK how you can say it was engineered properly

The dial crank cockpit trim adjust device has been in place long
before MCAS got incorporated into this model.

when if the trim
runs away signifcantly,

No. MCAS dialed the trim to its extent in one direction and the
pilots in these cases did not override the faulty MCAS operation in
time.

The stabilizer trim dials work fine and are not merely on Boeing
airframes.

puts the plane into a steep dive that
increases the necessary force, a pilot doesn't have enough strength
to overcome it.

Still MCAS to blame not the cockpit connection to the stabilizer.
That hard connection is the last resort in a failure and has been in
the basic design book for a long time. Long before 737Max8.

What's interesting is that apparently it hasn't
been a problem in the last half century, where trim ran away to
that extent, until now.

Trim never 'ran away to that extent' before. The MCAS was actively
driving against the pilot's attempts to adjust. MCAS has ran away.
Cockpit secondary stab controls have been in place for decades.

Far worse than spitting in the wind.

And if that fails, the pilot and co are right there to perform
the
tried and true.

Do not over complicate it.


Yeah, I figured you would ignore this part.

 

[Jan Panteltje]

On a sunny day (Sun, 30 Jun 2019 20:20:17 -0000 (UTC)) it happened Gunther
Heiko Hagen <guntherxxx@quantserve.de> wrote in <qfb5i1$qo6$14@dont-email.me>:

On Sun, 30 Jun 2019 11:20:16 -0700, trader4 wrote:

IDK how you can say it was engineered properly when if the trim runs
away signifcantly, puts the plane into a steep dive that increases the
necessary force, a pilot doesn't have enough strength to overcome it.
What's interesting is that apparently it hasn't been a problem in the
last half century, where trim ran away to that extent, until now.

They need to fix it fast before it attracts the "flying coffin" tag.

CNN says the grounding may last into 2021...

 

[Chris]

On 07/01/19 03:58, DLUNU wrote:

No. MCAS dialed the trim to its extent in one direction and the
pilots in these cases did not override the faulty MCAS operation in
time.

The stabilizer trim dials work fine and are not merely on Boeing
airframes.

Not quite. Because of the increased surface area on the max and
aerodynamic load at high speeds, the force required to counteract
the runaway mcas trim exceeds that which can be manually corrected
with the trim wheel. That's why both crashes were unrecoverable.

Chris

 

[Lasse Langwadt Christense]

mandag den 1. juli 2019 kl. 19.42.50 UTC+2 skrev Chris:

On 07/01/19 03:58, DLUNU wrote:


No. MCAS dialed the trim to its extent in one direction and the
pilots in these cases did not override the faulty MCAS operation in
time.

The stabilizer trim dials work fine and are not merely on Boeing
airframes.



Not quite. Because of the increased surface area on the max and
aerodynamic load at high speeds, the force required to counteract
the runaway mcas trim exceeds that which can be manually corrected
with the trim wheel. That's why both crashes were unrecoverable.

the surface area and the trim isn't different on the MAX

and aerodynamic load at high speed exceeding what you can correct
with the trimwheel can happen on any 737, it is even described in the manual

https://theaircurrent.com/wp-content/uploads/2019/04/1981-737-roller-coaster-recovery-1240x1903.jpg

 

[Chris]

On 07/01/19 18:55, Lasse Langwadt Christensen wrote:

mandag den 1. juli 2019 kl. 19.42.50 UTC+2 skrev Chris:
On 07/01/19 03:58, DLUNU wrote:


No. MCAS dialed the trim to its extent in one direction and the
pilots in these cases did not override the faulty MCAS operation in
time.

The stabilizer trim dials work fine and are not merely on Boeing
airframes.



Not quite. Because of the increased surface area on the max and
aerodynamic load at high speeds, the force required to counteract
the runaway mcas trim exceeds that which can be manually corrected
with the trim wheel. That's why both crashes were unrecoverable.

the surface area and the trim isn't different on the MAX

Not according to people who actually fly them and others who
should know about such things.

and aerodynamic load at high speed exceeding what you can correct
with the trimwheel can happen on any 737, it is even described in the manual

https://theaircurrent.com/wp-content/uploads/2019/04/1981-737-roller-coaster-recovery-1240x1903.jpg

Perhaps, but in the case of both crashes, mcas forced the nose down
at low altitude, where there was not enough height for recovery by
the roller coaster method.

There's a long running set of threads on this at the pprune site
here, going back ages: https://www.pprune.org/rumours-news-13/.
Worth having a look at to see how bad the situation really is...

Chris

 

[Lasse Langwadt Christense]

tirsdag den 2. juli 2019 kl. 02.02.23 UTC+2 skrev Chris:

On 07/01/19 18:55, Lasse Langwadt Christensen wrote:
mandag den 1. juli 2019 kl. 19.42.50 UTC+2 skrev Chris:
On 07/01/19 03:58, DLUNU wrote:


No. MCAS dialed the trim to its extent in one direction and the
pilots in these cases did not override the faulty MCAS operation in
time.

The stabilizer trim dials work fine and are not merely on Boeing
airframes.



Not quite. Because of the increased surface area on the max and
aerodynamic load at high speeds, the force required to counteract
the runaway mcas trim exceeds that which can be manually corrected
with the trim wheel. That's why both crashes were unrecoverable.

the surface area and the trim isn't different on the MAX

Not according to people who actually fly them and others who
should know about such things.

everything I've heard from 737 pilots is that the difference between
MAX and NG is the engines and their position

and aerodynamic load at high speed exceeding what you can correct
with the trimwheel can happen on any 737, it is even described in the manual

https://theaircurrent.com/wp-content/uploads/2019/04/1981-737-roller-coaster-recovery-1240x1903.jpg

Perhaps, but in the case of both crashes, mcas forced the nose down
at low altitude, where there was not enough height for recovery by
the roller coaster method.

sure, but runaway trim could have caused a similar situation on any 737

There's a long running set of threads on this at the pprune site
here, going back ages: https://www.pprune.org/rumours-news-13/.
Worth having a look at to see how bad the situation really is...

yes it it pretty bad when a simple system failure can cause a unrecoverable
situation if you don't have lots of altitude to spare

 

[Lasse Langwadt Christense]

tirsdag den 2. juli 2019 kl. 03.59.56 UTC+2 skrev Rick C:

On Monday, July 1, 2019 at 1:42:50 PM UTC-4, Chris wrote:
On 07/01/19 03:58, DLUNU wrote:


No. MCAS dialed the trim to its extent in one direction and the
pilots in these cases did not override the faulty MCAS operation in
time.

The stabilizer trim dials work fine and are not merely on Boeing
airframes.



Not quite. Because of the increased surface area on the max and
aerodynamic load at high speeds, the force required to counteract
the runaway mcas trim exceeds that which can be manually corrected
with the trim wheel. That's why both crashes were unrecoverable.

Doesn't the aerodynamic load tend to restore the elevator to the neutral position? That's why some planes pivot the elevator near the center of loading. No?

doesn't help if the load is so high the screw binds up

 

[Rick C]

On Monday, July 1, 2019 at 1:42:50 PM UTC-4, Chris wrote:

On 07/01/19 03:58, DLUNU wrote:


No. MCAS dialed the trim to its extent in one direction and the
pilots in these cases did not override the faulty MCAS operation in
time.

The stabilizer trim dials work fine and are not merely on Boeing
airframes.



Not quite. Because of the increased surface area on the max and
aerodynamic load at high speeds, the force required to counteract
the runaway mcas trim exceeds that which can be manually corrected
with the trim wheel. That's why both crashes were unrecoverable.

Doesn't the aerodynamic load tend to restore the elevator to the neutral position? That's why some planes pivot the elevator near the center of loading. No?

--

Rick C.

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