Boeing 737 MAX

[ChristineM]

Just heard on the news that the 737 max is grounded in every country in the world, except America.

 

[metis]

I think they should be temporarily grounded until what's in the black boxes is determined as the last two crashes have a similar pattern, and these were brand new planes.

IOW, better to be safe than sorry.

 

[Revoltingest]

Yeah the sensors or the program interacting with them was reporting falsely that the plane was about to stall, causing the nosedive in the end. We're still waiting to see if the Ethiopian liner had the same issues as the Indonesian, but at least Boeing has already promised(according to newspaper) to roll out a software patch around next week.

This is one of those control system design situation wherein I'm
so tempted to imagine what's going on, but I don't have enuf info.
I feel like a cat stalking a squirrel (nothing personal, @beenherebeforeagain).
The urge to pounce upon the furry little problem is very compelling.
Must figure out & fix!

 

[esmith]

This is one of those control system design situation wherein I'm
so tempted to imagine what's going on, but I don't have enuf info.
I feel like a cat stalking a squirrel (nothing personal, @beenherebeforeagain).
The urge to pounce upon the furry little problem is very compelling.
Must figure out & fix!

Was listing to someone on the news and they said that the problem probably lies with a runaway horizontal stabilizer trim issue as described in AD #: 2018-23-51 of November 7, 2018.
http://rgl.faa.gov/Regulatory_and_G...25833e0070a070/$FILE/2018-23-51_Emergency.pdf

"This emergency AD was prompted by analysis performed by the manufacturer showing that if an erroneously high single angle of attack (AOA) sensor input is received by the flight control system, there is a potential for repeated nose-down trim commands of the horizontal stabilizer. This condition, if not addressed, could cause the flight crew to have difficulty controlling the airplane, and lead to excessive nose-down attitude, significant altitude loss, and possible impact with terrain".

Runaway Stabilizer In the event of an uncommanded horizontal stabilizer trim movement, combined with any of the following potential effects or indications resulting from an erroneous Angle of Attack (AOA) input, the flight crew must comply with the Runaway Stabilizer procedure in the Operating Procedures chapter of this manual:

Now one would assume that if one is not fully checked out and or does not receive sufficient training on the B737MAX and this situation arises very possibly could screw-the-pooch.

 

[Shad]

It could be, but almost any site I look at says that their record before this incident is up to western standards. The airliner is considered to have an exceptionally good record, with modern operating procedures and new equipment. The captain had 8000 flight hours. Still, it's human to fail, so who knows.

Could be but maintenance logs can be falseified

It's an exceptional situation. Two of the same line crashing within a short time and it's very new with only a few of them flying so far. The percentage of deadly crashes on the plane exceeds number where we can be worried with reason, not hysteria.

After two years of no accidents.

I never said it was hysteria but that for one type of transportation government will ground yet while cars no such action.

If black boxes show something else then they'll continue to fly. In any case Boeing is making a software patch next week according to what I read in the papers. Google finds other articles on that:

Boeing To Make Key Change in 737 MAX Cockpit Software - Slashdot

The problem goes beyond software and into fly-by wire systems with no manual backup

 

[esmith]

12:38PM MDST Wed. March 13th President issues emergency order grounding all 737 Max 8 and Max 9 aircraft

 

[Revoltingest]

Could be but maintenance logs can be falseified

But is this hypothetical or a real problem?
We also don't yet know details about the pilots or the training.
Even the best & very experienced pilots can be lacking in critical ways at times.
(Air France Flight 296 in 1988...their experienced test pilot mishandled an A320.
Shortcomings with the A320 notwithstanding, the pilot behaved dangerously.)

Only a thorough investigation will shed light on all the possibilities.

The problem goes beyond software and into fly-by wire systems with no manual backup

Manual backup appears to be neither economical nor useful anymore.
What they do have is manual override of various facets of automation,
& this is a tricky thing to design. Planes have crashed when pilots thought
they knew better than autopilot, but the latter would've prevented disaster.
(I can't recall which crash I was thinking of.) It's complex to decide how
much control either pilots or the computer should have & when. Optimum
safety is a complicated & varying mixture of the 2. But things are inexorably
heading in the direction of computers having more control.

Note:
Fly by wire with no mechanical backup goes back to the early 70s,
eg, the YF-16, which became the F-16.

 

[Jumi]

Could be but maintenance logs can be falseified

Public track records can't be though.

After two years of no accidents.

As you can see in this thread, there were incidents in the US before Indonesia crash. Boeing was quietly and slowly working on a patch since then, that they announced they would roll out.

I never said it was hysteria but that for one type of transportation government will ground yet while cars no such action.

Yeah, what about cars? Just last year Toyota issued a recall for a million cars. People don't want garbage transportation like the Soviet Union had.

The problem goes beyond software and into fly-by wire systems with no manual backup

Of course there's more problems than just bad design without redundancy.

Trump decided to ground the planes and even Boeing now recommends you don't fly them for the time being.

 

[Jumi]

Just heard on the news that the 737 max is grounded in every country in the world, except America.

Looks like Trump is on board now too...

Trump says FAA will ground Boeing 737 MAX 8, 737 MAX 9 planes following deadly Ethiopian Airlines crash

 

[ChristineM]

Looks like Trump is on board now too...

Trump says FAA will ground Boeing 737 MAX 8, 737 MAX 9 planes following deadly Ethiopian Airlines crash

Good, it must be sorted, passengers lives matter

 

[Revoltingest]

Good, it must be sorted, passengers lives matter

But other than politically, is it the right decision?
People who don't fly in the 737 Max 8 planes will do a mix of....
- Drive by car instead.
- Take trains or buses instead.
- Fly in a different plane now.
- Skip the trip.
There's a real question is if the result is safer overall.
I don't know.

 

[ChristineM]

But other than politically, is it the right decision?
People who don't fly in the 737 Max 8 planes will do a mix of....
- Drive by car instead.
- Take trains or buses instead.
- Fly in a different plane now.
- Skip the trip.
There's a real question is if the result is safer overall.
I don't know.

Sure its not safer,
Does that mean its right to let faulty aircraft fly?
Does that mean its right to play russian roulette with passengers?

 

[esmith]

Sure its not safer,
Does that mean its right to let faulty aircraft fly?
Does that mean its right to play russian roulette with passengers?

There has not been any evidence, as of now, that indicates that the aircraft is faulty.
One should not jump to conclusions.

 

[ChristineM]

There has not been any evidence, as of now, that indicates that the aircraft is faulty.
One should not jump to conclusions.

Ok, just let them crash and kill people

 

[esmith]

Ok, just let them crash and kill people

No, you ground them until the facts are known.
What you don't do is jump to conclusions. Which you seem to have done.

 

[ChristineM]

No, you ground them until the facts are known.
What you don't do is jump to conclusions. Which you seem to have done.

What conclusion have i drawn, people have died in 2 crashes of that model plane. And there have been at least 2 reported incidents of similar failures

I dont know about you but i have a problem with that?

 

[Revoltingest]

Sure its not safer,
Does that mean its right to let faulty aircraft fly?
Does that mean its right to play russian roulette with passengers?

We don't yet know the nature of the faults, which could be mechanical,
software, pilot, airline, or maintenance.
(Typically a crash involves more than one failure/problem, which occur
simultaneously.) We don't know that it's safer to ground all these planes
because we all play "Russian roulette" when we travel by any means.
What people feel is safe, is often more dangerous. There would be a
greater likelihood of few people dying compared to the larger number
of deaths in each rare plane crash. So this would require some
quantitative analysis in order to make an objective decision.

It should worry many that they agree with Trump on this.

 

[ChristineM]

We don't yet know the nature of the faults, which could be mechanical,
software, pilot, airline, or maintenance.
(Typically a crash involves more than one which occur simultaneously.)
We don't know that it's safer to ground all these planes because we all play
"Russian roulette" when we travel by any means. What people feel is safe,
is often more dangerous. There would be a greater likelihood of few people
dying compared to the larger number of deaths in each rare plane crash.
So this would require some quantitative analysis in order to make an
objective decision.

It should worry many that they agree with Trump on this.

Does it matter what the problem is. Given current stats it would not be rare much longer if they were not grounded. The stats are compiled by passenger flights, not by aircraft model
How many more crashes are needed to change the statistics. Would the airlines be guilty of murder if these planes were not grounded and another crashed?
Would people (including you) be happy to fly in a plane with such a record.
This needs to be sorted no matter what the problem

Trump is pandering to world opinion, its not people agreeing with trump but just the opposite.

 

[Revoltingest]

Does it matter what the problem is. Given current stats it would not be rare much longer if they were not grounded. The stats are compiled by passenger flights, not by aircraft model

What statistical analysis is there for the 737 Max 8?
(I searched, & didn't find anything.)

How many more crashes are needed to change the statistics. Would the airlines be guilty of murder if these planes were not grounded and another crashed?
Would people (including you) be happy to fly in a plane with such a record.
This needs to be sorted no matter what the problem

I wouldn't fear flying in a 737 Max 8 more than other planes.
(Older ones concern me because aluminum has limited fatigue life.
but carbon fiber fuselages are brittle. There are many risk factors.)
My feelings on this don't matter.
What does matter is that decisions not be made based upon emotion.
Actuaries & aircraft experts are needed.

Trump is pandering to world opinion, its not people agreeing with trump but just the opposite.

I spoke of people who make Trump out to always be evil & wrong, yet want the planes grounded.
I wondered if agreeing with him makes them uncomfortable?

 

[esmith]

What conclusion have i drawn, people have died in 2 crashes of that model plane. And there have been at least 2 reported incidents of similar failures

I dont know about you but i have a problem with that?

You said the crashes was a fault of the plane. Obviously you have factual information beyond even Boeing and the FAA

Sure its not safer,
Does that mean its right to let faulty aircraft fly?