Moderators: jsumali2, richierich, ua900, PanAm_DC10, hOMSaR

 
Interested
Posts: 887
Joined: Thu May 19, 2016 12:19 pm

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 6:58 pm

WPIAeroGuy wrote:
XRAYretired wrote:
WPIAeroGuy wrote:

What do you want Boeing to do? Put out a press release saying "Hey sorry we built a deathtrap, guess we'll put a few billion into the 797 instead?". You're not even being reasonable. MCAS in its initial implementation was poorly designed. No one here will argue that. You (and others) keep saying the MAX was 'badly designed' because it had certain undesirable characteristics. Well guess what, every freaking airplane flying has undesirable characteristics that are the result of a compromise in some part of the design. Is every airplane with vortex generators, stall strips, or wing fences a bad design because they required modifications to improve stall characteristics?

It's clear how many people posting have never held a real engineering position. An engineers job is not to make the best performing product ever. It's to produce a product that meets the design goals while minimizing cost. Did you expect Boeing to get to flight testing of the MAX, notice a non-linearity in the pitch controls, and just say "well that design didn't work, let's start from scratch?" They know they screwed up MCAS. Unless there is evidence that there was knowledge that safety would be compromised with the initial MCAS implementation (and no, the fact that something could be made safer does not mean it was unsafe to begin with) then I will not condemn Boeing. I will expect them to be responsible financially for any and all reparations to the victims families, the airlines with grounded MAXes, and anyone else affected.


It was unsafe to begin with. Knowingly, or unknowingly - negligent. (40yrs Deign, Development and Manufacture Aerospace and Defence) In my opinion. System design should not have got through step 1, In my opinion.

Ray


What do you mean 'to begin with?' The extent of the high AoA pitching moment change wasn't known until flight testing. The MCAS implementation was bad, but that doesn't mean a 737 that needs (a more robust version of) MCAS is a bad design.


You talk about people on here not knowing anything engineering. Then you have the audacity to describe a more robust version of MCAS as not a bad design?

It's not even worthy of being called a design. Engineers at Boeing made mistakes early on and had to create a bandage for their failed design. Now their bandage has disastrously failed twice you claim the new version is not going to be a bad design. Design is the wrong word - it's a more robust bandage they are trying to create
 
XRAYretired
Posts: 870
Joined: Fri Mar 15, 2019 11:21 am

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 6:58 pm

WPIAeroGuy wrote:
XRAYretired wrote:
WPIAeroGuy wrote:

What do you want Boeing to do? Put out a press release saying "Hey sorry we built a deathtrap, guess we'll put a few billion into the 797 instead?". You're not even being reasonable. MCAS in its initial implementation was poorly designed. No one here will argue that. You (and others) keep saying the MAX was 'badly designed' because it had certain undesirable characteristics. Well guess what, every freaking airplane flying has undesirable characteristics that are the result of a compromise in some part of the design. Is every airplane with vortex generators, stall strips, or wing fences a bad design because they required modifications to improve stall characteristics?

It's clear how many people posting have never held a real engineering position. An engineers job is not to make the best performing product ever. It's to produce a product that meets the design goals while minimizing cost. Did you expect Boeing to get to flight testing of the MAX, notice a non-linearity in the pitch controls, and just say "well that design didn't work, let's start from scratch?" They know they screwed up MCAS. Unless there is evidence that there was knowledge that safety would be compromised with the initial MCAS implementation (and no, the fact that something could be made safer does not mean it was unsafe to begin with) then I will not condemn Boeing. I will expect them to be responsible financially for any and all reparations to the victims families, the airlines with grounded MAXes, and anyone else affected.


It was unsafe to begin with. Knowingly, or unknowingly - negligent. (40yrs Deign, Development and Manufacture Aerospace and Defence) In my opinion. System design should not have got through step 1, In my opinion.

Ray

What do you mean 'to begin with?' The extent of the high AoA pitching moment change wasn't known until flight testing. The MCAS implementation was bad, but that doesn't mean a 737 that needs (a more robust version of) MCAS is a bad design.

"Unless there is evidence that there was knowledge that safety would be compromised with the initial MCAS implementation (and no, the fact that something could be made safer does not mean it was unsafe to begin with) then I will not condemn Boeing."

Ray
 
FlyBitcoin
Posts: 96
Joined: Tue Nov 06, 2018 3:38 am

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 7:00 pm

OldAeroGuy wrote:
Interested wrote:
OldAeroGuy wrote:

Well said, I think you've got it right.

EASA will probably re-certify the MAX with MCAS.v2. While they may require additional simulator time but it will probably involve the "AoA Disagree" symbology that will now be on every MAX as it's a new feature and its relationship to "Runaway Stab" and "Unreliable Airspeed" training.

They may also address proper procedures for dealing with sticker activation during takeoff. This is a linking event for JT043, JT610 and ET302 and none of the crews dealt with it well. MCAS was not an issue when dealing with early stick shaker activation.


So you are happy to introduce extra risks to a plane that was previously safer to fly? (The NG that is)

Why would you accept a plane that needs this add on?

It's clearly riskier than not needing it at all?

Why are we accepting extra risks with such an important plane? What do we gain by the extra risks?


To start this discussion, let's look at some accident statistics:

737 NG Series: .09 accidents per million departures with a hull loss and fatalities

A320 Series: .11 accidents per million departures with a hull loss and fatalities

Source: https://www.skybrary.aero/bookshelf/books/4239.pdf

From these data, the 737 NG and A320 have essentially the same fatal accident rate.

Both airplanes have trimmable horizontal stabilizers and both are subject to "STAB Runaway". "STAB Runaway" events and Crew actions to deal with the Runaways are included in the accident statistics.

As barneycaptain points out, the 737 NG has five failure modes that can cause a "STAB Runaway". MCAS added a sixth mode for the MAX. All six modes were dealt with by using the same "STAB Runaway" procedure. If Crews can deal properly with the initial five failure modes, they should be able to deal with the sixth.

When the 737 MAX fatal accident statistics are published, they will look horrific. The reasons are the botched implementation of MCAS, the high MAX AoA vane failure rate and Crew errors in applying "Stabilizer Runaway" procedures.

When MCAS.v2 is incorporated, I'm confident that a single AoA vane signal failure will not erroneously activate MCAS and the MAX accident rate will drop to the NG historic level.

If AoA vane failure rates also drop to historic levels, it will make me even more confident.


Assuming all MAX deliveries resume at the planned rate once the grounding is lifted worldwide, and the plane has a flawless safety record for 5 years, then it will still have a much higher rate of accident with hull loss compared to the NG and 320. It will take longer than 5 years to normalize that data.

And until that data is normalized, can you blame a member of the flying public for avoiding the MAX until it has proven to normalize its accident rate compared other aircraft that likely are flying the same route?
 
Interested
Posts: 887
Joined: Thu May 19, 2016 12:19 pm

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 7:01 pm

Definition of safety engineering:

Safety engineering is the process of design o prevent accidents. Engineering Safety Concepts provide detailed approaches and modes for accident reduction by using a risk management process to identify and "design out" hazards.

Do Boeing employ "unsafety engineers"?

They've managed to "design" (I use the word loosely) a plane that "designs in" hazards

How is that possible in this day and age

They wanted a more fuel efficient plane and this is their answer?

Unacceptable. This design should never have got past the drawing board stage. It should have been rejected before any engines even got moved etc.

It's a shambolic design
 
Jamie514
Posts: 154
Joined: Thu May 18, 2017 4:36 pm

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 7:06 pm

XRAYretired wrote:
Jamie514 wrote:
ACCS300 wrote:

Except that Canadian carriers are likely the most effected, per capita, by the MAX grounding of perhaps any country in the world. For Air Canada, it's almost 1/4 of their narrow body fleet, less so for Westjet. AC is likely the most effected major carrier in the world on a percentage of fleet basis. Transport Canada will likely bow somewhat to the pressure of Canadian carriers to a degree. AC also has MAX simulators on hand.


AC with their simulators and having not transitioned off NG, is probably among the best positioned to cope with additional training directives. I also think these measures will go a ways toward restoring public confidence in the plane, which Air Canada's unique fleet composition makes them most exposed to.

I'm interested to see how it plays out with regards to airlines under FAA jurisdiction operating over Canada. Like, will any of the US operators push back on the purported Canadian simulator training requirements for MAX operation. Even if their MAX isn't serving Canadian cities, they would surely use the airspace from time to time on transcons to Seattle or routes to Alaska.


If, and its probably still a big if, Canada prohibits flight in their airspace in such circumstances. Are you suggesting that US carriers might infringe illegally the airspace of a sovereign country? If you want a political storm with US closest (geographically) ally and neighbour, that would be a good way to instigated a whopper.

Ray


No. By push-back, I am only wondering if the US carriers or the FAA as certifying body might seek an exemption of some sort, using diplomatic/political/lobby channels before committing to the investment required to meet any Canadian requirements.

If no such agreement was possible, expected outcome would be a commitment to meeting the training requirements or to ensure any "non-compliant" MAX operations were kept clear of Canadian airspace.
 
XRAYretired
Posts: 870
Joined: Fri Mar 15, 2019 11:21 am

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 7:11 pm

Jamie514 wrote:
XRAYretired wrote:
Jamie514 wrote:

AC with their simulators and having not transitioned off NG, is probably among the best positioned to cope with additional training directives. I also think these measures will go a ways toward restoring public confidence in the plane, which Air Canada's unique fleet composition makes them most exposed to.

I'm interested to see how it plays out with regards to airlines under FAA jurisdiction operating over Canada. Like, will any of the US operators push back on the purported Canadian simulator training requirements for MAX operation. Even if their MAX isn't serving Canadian cities, they would surely use the airspace from time to time on transcons to Seattle or routes to Alaska.


If, and its probably still a big if, Canada prohibits flight in their airspace in such circumstances. Are you suggesting that US carriers might infringe illegally the airspace of a sovereign country? If you want a political storm with US closest (geographically) ally and neighbour, that would be a good way to instigated a whopper.

Ray

Apologies for miss-interpreting you intention.

No. By push-back, I am only wondering if the US carriers or the FAA as certifying body might seek an exemption of some sort, using diplomatic/political/lobby channels before committing to the investment required to meet any Canadian requirements.

If no such agreement was possible, expected outcome would be a commitment to meeting the training requirements or to ensure any "non-compliant" MAX operations were kept clear of Canadian airspace.

Apologies for miss-interpreting you intention.
So much confrontation on these threads its easy to get drawn in un-intentionally.

Ray
 
Amiga500
Posts: 2645
Joined: Tue Mar 03, 2015 8:22 am

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 7:29 pm

WPIAeroGuy wrote:
What do you mean 'to begin with?'


That is blindingly obvious.

Lets start with 1 sensor input.
 
smartplane
Posts: 1471
Joined: Fri Aug 03, 2018 9:23 pm

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 7:50 pm

Heinkel wrote:
I have the stange feeling, that all those people from the failed "MAX grounding is not necessary" bandwagon now jump on the "MAX sim training is not necessary" bandwagon. Ok, we know, there are (at least) 280 million reasons for that opinion. Lady Gaga only asked for a million reasons.

The PR effort seems to have admitted defeat on the training requirements. Now it's a last stand on simulator time.

PR focus now is on protecting MAX certification / grandfathering, protecting 777X certification / grandfathering methodology, and for good measure, if you move on Boeing make sure you include Airbus (which is why Airbus are now openly supporting Boeing).
 
WPIAeroGuy
Posts: 323
Joined: Tue Aug 21, 2007 11:52 pm

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 7:55 pm

Amiga500 wrote:
WPIAeroGuy wrote:
What do you mean 'to begin with?'


That is blindingly obvious.

Lets start with 1 sensor input.


I was asking XRAYretired to clarify if he was referring to the concept of a 737MAX being unsafe or specifically MCAS implementation. It is now clear he meant MCAS implementation.
-WPIAeroGuy
 
barney captain
Posts: 2337
Joined: Tue Nov 06, 2001 5:47 pm

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 8:00 pm

xmp125a wrote:
barney captain wrote:
OldAeroGuy wrote:

No amount of simulator time would have eliminated the need for MCAS on the MAX. The issue was that the MAX stall entry Flaps Up did not meet the certification requirement for steadily increasing stick force until the airplane stalls. MCAS was a solution to this problem. The MAX is not the first airplane to have this issue and the solutions range from aerodynamic to electronic and/or combinations of the two.

And once again, MCAS was not a stall prevention device. The pilot could still stall the MAX with MCAS operating. MCAS was designed to make sure the stall entry stick force did not "lighten" duding the stall entry.


Be very careful Sir - you're teetering on professional observations backed up with knowledge, experience and sound reasoning.

There's very little room for that here. :bigthumbsup:


Don't be insulting. I have explained myself - I am engineer, not a pilot. I am here to get opinions and facts from the people more knowledgeable to me, because I am in position to traing young people on system desgn and engineering. Regarding MCAS, we don't have even good idea what exactly was MCAS intended to be, and suspicions that MCAS was declared as X while being X, Y and Z at the one time are not entirely unfounded.


X, none of what I wrote was directed at you - you just got caught up in the quote.
Southeast Of Disorder
 
smartplane
Posts: 1471
Joined: Fri Aug 03, 2018 9:23 pm

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 8:05 pm

WPIAeroGuy wrote:
blrsea wrote:
MCAS was a commercial requirement, not an engineering requirement. It was added so that Max handling characteristics was same as NG, to prevent additional training which could cost Boeing sales or reduced profits.

Why introduce additional points of failure even though it *might* have been mitigated in new design? It is not serving any engineering problem, just so that Boeing can use it to do more sales. Keep it simple from engineering perspective even if it means additional training/certification. No need to increase surface area for errors when there is no fundamental reason to do so


I hate sales guys as much as the next engineer, but there's no point in designing an airplane if no one is going to buy it. The airlines wanted a more efficient 737. That's what they got.

Got it. It's the airlines fault!
 
XRAYretired
Posts: 870
Joined: Fri Mar 15, 2019 11:21 am

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 8:07 pm

WPIAeroGuy wrote:
Amiga500 wrote:
WPIAeroGuy wrote:
What do you mean 'to begin with?'


That is blindingly obvious.

Lets start with 1 sensor input.


I was asking XRAYretired to clarify if he was referring to the concept of a 737MAX being unsafe or specifically MCAS implementation. It is now clear he meant MCAS implementation.


MCAS v2 looks like they are going to fix the mess they got in to. I would assume they are reviewing the whole thing to make sure nothing else is amiss and that may very well explain the delay in the fix ostensibly due to a problem with flap system? I would also expect a review of similar design changes in other frames for the past few? years, depending upon what they believe the root causes are. I would expect FAA etc. will have a hand in these reviews.

Ray
 
WPIAeroGuy
Posts: 323
Joined: Tue Aug 21, 2007 11:52 pm

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 8:19 pm

Interested wrote:
Definition of safety engineering:

Safety engineering is the process of design o prevent accidents. Engineering Safety Concepts provide detailed approaches and modes for accident reduction by using a risk management process to identify and "design out" hazards.

Do Boeing employ "unsafety engineers"?

They've managed to "design" (I use the word loosely) a plane that "designs in" hazards

How is that possible in this day and age

They wanted a more fuel efficient plane and this is their answer?

Unacceptable. This design should never have got past the drawing board stage. It should have been rejected before any engines even got moved etc.

It's a shambolic design


I've tried to explain many times in multiple threads how this could have happened. Instead of trying to understand how a design like this could have been implemented, you'd rather use your benefit of hindsight to disparage a decision making process of which you have zero insight to.

I was not part of this process either, but I'm going to speculate on why the initial FMEA concluded that one AoA sensor was acceptable: MCAS was required to meet certification requirements, but the aircraft could still be flown safely without it. Therefore, rather than add redundant inputs (which you would if it was imperative the system remain operating), the engineers chose to have a fail-safe cutout (cut power to the electric trim motors) in the event of a malfunction, which they (incorrectly) assumed would be identified as a runaway trim problem.
-WPIAeroGuy
 
WPIAeroGuy
Posts: 323
Joined: Tue Aug 21, 2007 11:52 pm

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 8:21 pm

smartplane wrote:
WPIAeroGuy wrote:
blrsea wrote:
MCAS was a commercial requirement, not an engineering requirement. It was added so that Max handling characteristics was same as NG, to prevent additional training which could cost Boeing sales or reduced profits.

Why introduce additional points of failure even though it *might* have been mitigated in new design? It is not serving any engineering problem, just so that Boeing can use it to do more sales. Keep it simple from engineering perspective even if it means additional training/certification. No need to increase surface area for errors when there is no fundamental reason to do so


I hate sales guys as much as the next engineer, but there's no point in designing an airplane if no one is going to buy it. The airlines wanted a more efficient 737. That's what they got.

Got it. It's the airlines fault!


That is NOT what I said. Don't put words in my mouth, it does not help your argument.
-WPIAeroGuy
 
User avatar
SheikhDjibouti
Posts: 2124
Joined: Sat Sep 30, 2017 4:59 pm

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 8:26 pm

OldAeroGuy wrote:
To start this discussion, let's look at some accident statistics:

737 NG Series: .09 accidents per million departures with a hull loss and fatalities

A320 Series: .11 accidents per million departures with a hull loss and fatalities

Source: https://www.skybrary.aero/bookshelf/books/4239.pdf

From these data, the 737 NG and A320 have essentially the same fatal accident rate.

FlyBitcoin wrote:
Assuming all MAX deliveries resume at the planned rate once the grounding is lifted worldwide, and the plane has a flawless safety record for 5 years, then it will still have a much higher rate of accident with hull loss compared to the NG and 320. It will take longer than 5 years to normalize that data.

And until that data is normalized, can you blame a member of the flying public for avoiding the MAX until it has proven to normalize its accident rate compared other aircraft that likely are flying the same route?

Unfortunately the world is too often fed lazy interpretations of statistics such as all of the above.
For instance, most hull losses occur on or near the runway, often without fatalities.
We should be able to park these two MAX crashes as something that happened with MAX v1.0 (feat MCAS v1.0!)
Entirely regrettable, and Boeing will quite rightly pay a heavy price for that.

NeoMAX v2.0, (or whatever the new variant is called) should start with a clean slate. Or at least, the generic 737 (all versions) accident rate.

With one single caveat; if NeoMAX v2.0 also encounters problems that can be traced back to MCAS, or lack of sim training, or lack of authority on either the trim wheel or the thumb switches, or anything else that was a contributory factor in JT610 or ET302, then we should pile on the previous two crashes.

Aside from that, there has got to be reasonableness.
Hull losses from heavy landings, windshear on final approach, runway excursions, or suicidal pilots, are all things that could happen to any type.
Whether the greedy headline-seeking media at large will abide by this noble concept is another matter.
We here on a.net should be better than that.
Nothing to see here; move along please.
 
hivue
Posts: 2076
Joined: Tue Feb 26, 2013 2:26 am

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 8:28 pm

blrsea wrote:
No, they would have still got a fuel efficient new aircraft with probably >95% commonality, but just a little additional training on where Max differs from NG if MCAS was excluded


If MCAS had been excluded and not replaced by some other strategy the airplane would not have met certification requirements. Whether that some other strategy would have required just a little or just a lot of additional training we will never know. Boeing likely felt it would require just a lot.
"You're sitting. In a chair. In the SKY!!" ~ Louis C.K.
 
RickNRoll
Posts: 1869
Joined: Fri Jan 06, 2012 9:30 am

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 9:06 pm

asdf wrote:
RickNRoll wrote:
... from what I have read the better procedure to follow would have been unreliable air speed.


in the aftermath its easy
Boeing would have known exactly what happened and why. They chose to play down the severity of the pilot experience and put out a bulletin that made it sound a lot simpler than it was in reality.
 
Amiga500
Posts: 2645
Joined: Tue Mar 03, 2015 8:22 am

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 9:08 pm

WPIAeroGuy wrote:
I was not part of this process either, but I'm going to speculate on why the initial FMEA concluded that one AoA sensor was acceptable: MCAS was required to meet certification requirements, but the aircraft could still be flown safely without it. Therefore, rather than add redundant inputs (which you would if it was imperative the system remain operating), the engineers chose to have a fail-safe cutout (cut power to the electric trim motors) in the event of a malfunction, which they (incorrectly) assumed would be identified as a runaway trim problem.


Given how the two failures (runaway and MCAS) would present themselves; no engineer worth a damn would ever assume they would be identified as the same problem.

Either Boeing's engineers on this system architecture, the software design, software verification and on the stability & control - through PDR & CDR were all rubbish - or someone up the food chain decreed that no further deactivation switches could be added to the cockpit or that no FCOM section indicating how MCAS failure might present itself would be incorporated.
 
MrBretz
Posts: 536
Joined: Tue Jun 14, 2016 9:13 pm

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 9:12 pm

WPIAeroGuy wrote:
Interested wrote:
Definition of safety engineering:

Safety engineering is the process of design o prevent accidents. Engineering Safety Concepts provide detailed approaches and modes for accident reduction by using a risk management process to identify and "design out" hazards.

Do Boeing employ "unsafety engineers"?

They've managed to "design" (I use the word loosely) a plane that "designs in" hazards

How is that possible in this day and age

They wanted a more fuel efficient plane and this is their answer?

Unacceptable. This design should never have got past the drawing board stage. It should have been rejected before any engines even got moved etc.

It's a shambolic design


I've tried to explain many times in multiple threads how this could have happened. Instead of trying to understand how a design like this could have been implemented, you'd rather use your benefit of hindsight to disparage a decision making process of which you have zero insight to.

I was not part of this process either, but I'm going to speculate on why the initial FMEA concluded that one AoA sensor was acceptable: MCAS was required to meet certification requirements, but the aircraft could still be flown safely without it. Therefore, rather than add redundant inputs (which you would if it was imperative the system remain operating), the engineers chose to have a fail-safe cutout (cut power to the electric trim motors) in the event of a malfunction, which they (incorrectly) assumed would be identified as a runaway trim problem.


This is a very rational post. Boeing wasn’t being evil. It was just not thought out completely. It will be corrected. And additional training in whatever form will happen. Boeing will paying the victims and airlines something. The plane will be safer. No engineer is trying to kill anyone. However, someone should take a fall. I wish they would can the CEO, take back his stock options, and pay for the last 5 years.
 
Interested
Posts: 887
Joined: Thu May 19, 2016 12:19 pm

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 9:30 pm

The plane will be safer than it is now but can't be as safe as the plane it was SUPPOSED to be grandfathered from

It's not evil at all. It's just awful design with fuel efficiency put ahead of safety

And it's going to prove to be the most expensive mistake ever made in the airline industry to date (both short and long term)

Please don't tell me that behind closed doors Boeing senior management aren't shaking their heads and thinking how do we get ourselves through this and out of this
 
Heinkel
Posts: 244
Joined: Sun Sep 08, 2013 6:15 pm

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 9:59 pm

WPIAeroGuy wrote:
I hate sales guys as much as the next engineer, but there's no point in designing an airplane if no one is going to buy it. The airlines wanted a more efficient 737. That's what they got.


A death trap? Much worse safety record than the previous model? Yes, but more efficient! Needs less fuel, makes more money. Safety vs. economy. Greed is good!
 
Absynth
Posts: 82
Joined: Wed Apr 17, 2019 5:37 pm

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 10:01 pm

SheikhDjibouti wrote:
OldAeroGuy wrote:
To start this discussion, let's look at some accident statistics:

737 NG Series: .09 accidents per million departures with a hull loss and fatalities

A320 Series: .11 accidents per million departures with a hull loss and fatalities

Source: https://www.skybrary.aero/bookshelf/books/4239.pdf

From these data, the 737 NG and A320 have essentially the same fatal accident rate.

FlyBitcoin wrote:
Assuming all MAX deliveries resume at the planned rate once the grounding is lifted worldwide, and the plane has a flawless safety record for 5 years, then it will still have a much higher rate of accident with hull loss compared to the NG and 320. It will take longer than 5 years to normalize that data.

And until that data is normalized, can you blame a member of the flying public for avoiding the MAX until it has proven to normalize its accident rate compared other aircraft that likely are flying the same route?


NeoMAX v2.0, (or whatever the new variant is called) should start with a clean slate. Or at least, the generic 737 (all versions) accident rate.

With one single caveat; if NeoMAX v2.0 also encounters problems that can be traced back to MCAS, or lack of sim training, or lack of authority on either the trim wheel or the thumb switches, or anything else that was a contributory factor in JT610 or ET302, then we should pile on the previous two crashes.

Aside from that, there has got to be reasonableness.
Hull losses from heavy landings, windshear on final approach, runway excursions, or suicidal pilots, are all things that could happen to any type.
Whether the greedy headline-seeking media at large will abide by this noble concept is another matter.
We here on a.net should be better than that.


I'm sorry but this is not how safety records work or shoudl work. Either the airplane is at fault, or it isnt. What you are stating is that all cases where the airplane is not at fault (suicides, accidents with birds etc.) shouldnt be counted, and cases where the airplane is at fault should also not be caunted. All planes that have been found at fault will have to correct the things that caused the crash or accident. Your scenario would have every plane with a spotless track record, even if the manufacturer literally had to correct dozens of faults that caused dozens of deadly accidents.

MAX v14.0 has a completely spotless track record. It's the safest airplane ever!
 
User avatar
SomebodyInTLS
Posts: 1840
Joined: Wed Jun 15, 2016 12:31 pm

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 10:15 pm

hivue wrote:
SomebodyInTLS wrote:
the intention of the system is to prevent the pilot initiating stall - *for certification purposes*.


But MCAS 1.0 can't do that. Nobody intended for it to be able to do that. MCAS 2.0 will not be able to do that. Nobody intends for it to be able to do that.


Are you kidding?!

Of course the intention is - originally through "feel" but later through a good shove instead - for the pilot to be told "don't go there". Otherwise why would certification require that the stick gets heavier as you get closer to a stall??? For fun?
"As with most things related to aircraft design, it's all about the trade-offs and much more nuanced than A.net likes to make out."
 
User avatar
zeke
Posts: 14978
Joined: Thu Dec 14, 2006 1:42 pm

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 10:28 pm

Heinkel wrote:
A death trap? Much worse safety record than the previous model? Yes, but more efficient! Needs less fuel, makes more money. Safety vs. economy. Greed is good!


Got a good tune that goes well with that post https://youtu.be/kuzWLDWm6Zs
Human rights lawyers are "ambulance chasers of the very worst kind.'" - Sky News
 
Heinkel
Posts: 244
Joined: Sun Sep 08, 2013 6:15 pm

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 10:43 pm

zeke wrote:
Heinkel wrote:
A death trap? Much worse safety record than the previous model? Yes, but more efficient! Needs less fuel, makes more money. Safety vs. economy. Greed is good!


Got a good tune that goes well with that post https://youtu.be/kuzWLDWm6Zs


Hyperbole, yes. But only a bit. Boeing shares are surprisingly stable.
 
User avatar
zeke
Posts: 14978
Joined: Thu Dec 14, 2006 1:42 pm

Re: B737MAX Grounded Worldwide

Fri Apr 19, 2019 11:00 pm

Heinkel wrote:

Hyperbole, yes. But only a bit. Boeing shares are surprisingly stable.


That would be due to the engineering solution being a very minor software load. There would be a 737 taking off and landing every few seconds around the world, it is one of the safest aircraft around.
Human rights lawyers are "ambulance chasers of the very worst kind.'" - Sky News
 
MrBretz
Posts: 536
Joined: Tue Jun 14, 2016 9:13 pm

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 12:49 am

Boeing stock is at about the same price as it was last October. The market tanked at year end and Boeing soared back to something about 15% higher than yesterday's close. I think this means the market thinks Boeing has seen the worst. It certainly doesn't think they are going to lose a ton of money. But who know if the market really knows. I believe the fix and training will work. But I wouldn't be buying Boeing stock.
 
morrisond
Posts: 2664
Joined: Thu Jan 07, 2010 12:22 am

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 1:06 am

Interested wrote:
The plane will be safer than it is now but can't be as safe as the plane it was SUPPOSED to be grandfathered from

It's not evil at all. It's just awful design with fuel efficiency put ahead of safety

And it's going to prove to be the most expensive mistake ever made in the airline industry to date (both short and long term)

Please don't tell me that behind closed doors Boeing senior management aren't shaking their heads and thinking how do we get ourselves through this and out of this


Precisely how will the MAX not be as safe as the NG? Even if you have to turn off MCAS on the MAX due to a fault the only time the controls will get light on the MAX is if you are very light and full AFT COG. There is no inherent instability in the MAX vs the NG.

You have to pull through this light control feel and the stick shaker and the Audio warnings and the frame buffeting to actually get it to stall.

I don't think any pilot in the world would allow this to happen - it would have to be intentional and incredibly simple to recover from.

With MCAS functioning properly the MAX effectively now has an anti-stall system making it safer than the NG - no pilot in the MAX should ever hear a stall alarm or feel the stick shaker.
 
OldAeroGuy
Posts: 3921
Joined: Sun Dec 05, 2004 6:50 am

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 1:09 am

Interested wrote:
OldAeroGuy wrote:
Interested wrote:

So you are happy to introduce extra risks to a plane that was previously safer to fly? (The NG that is)

Why would you accept a plane that needs this add on?

It's clearly riskier than not needing it at all?

Why are we accepting extra risks with such an important plane? What do we gain by the extra risks?


As barneycaptain points out, the 737 NG has five failure modes that can cause a "STAB Runaway". MCAS added a sixth mode for the MAX. All six modes were dealt with by using the same "STAB Runaway" procedure. If Crews can deal properly with the initial five failure modes, they should be able to deal with the sixth.



So the 5 failure modes that can cause stab runaway on NG - are they serious and can they bring a plane down. And how often do they happen?


Yes, the other 5 modes can bring the plane down if the pilots do not recognize "STAB Runaway" and apply the appropriate procedures. It's worth noting that none of these 5 are called out specifically in the 737 QRH. They are all covered under a single "STAB Runaway" procedure.

They occur "Rarely". The purpose of MCAS.v2 is to reduce MCAS caused runaways to the "Rarely" category or less.

I was planning on writing more on the topic but I'm not sure it would help since you're sure of where you stand. You've stated the 737 MAX will not be re-certified.

In Reply 5569, I've stated what EASA will require to re-certify the 737 Max. Let's see who has the best prediction for 737 MAX history.

In the meantime, it might help you to read this document:

https://www.faa.gov/documentLibrary/med ... 040.4B.pdf

It will help you to understand how Safety Risk Analyses are performed and what a term like "Rarely" means.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
User avatar
par13del
Posts: 10262
Joined: Sun Dec 18, 2005 9:14 pm

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 1:28 am

Ok, so Boeing's stock tanks, then what, they use the dreaded Chpt.11 to clear pensions, union contracts, other debt, re-organize then start selling all their a/c at even greater give away prices, and the aviation industry is better because they start increasing their market share by selling a/c at prices Airbus cannot compete?
 
User avatar
zeke
Posts: 14978
Joined: Thu Dec 14, 2006 1:42 pm

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 1:35 am

OldAeroGuy wrote:
I was planning on writing more on the topic but I'm not sure it would help since you're sure of where you stand. You've stated the 737 MAX will not be re-certified.

In Reply 5569, I've stated what EASA will require to re-certify the 737 Max. Let's see who has the best prediction for 737 MAX history.


Not sure if recertification is the best term to use, the TC is still valid. The FAA issued an emergency order of prohibition, once the technical review is completed that order will be rescinded and the aircraft type can be flown again without recertification.
Human rights lawyers are "ambulance chasers of the very worst kind.'" - Sky News
 
tealnz
Posts: 635
Joined: Mon Nov 09, 2015 10:47 am

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 1:35 am

Revelation wrote:
Personally, if I was a pilot, I think I'd want sim time to at least build up the muscle memory for working with the now infamous trim wheel and cutout switches while in Muilenburg's "high workload environment", learn the "roller coaster" recovery, etc. I'm dubious that an hour or so with an iPad is going to help pilots re-gain confidence in the MAX product.


DenverTed wrote:
Fix the limits of MCAS, check. Fix the single AOA, check. Fix the switches back to the NG style, so you can turn off autopilot inputs to the electric motor but still use the electric trim? Will they do this? What if Speed Trim or Mach Trim malfunction on the stabilizer?


Count me as one more who's puzzled why we're not hearing more about manual trim and electric trim malfunction scenarios. I think it's been established that ability to adjust stabiliser using manual trim wheels was part of the basis on which MAX was given certification. Inability to use manual trim may have been a factor in the ET crash. We've been told that the change to smaller trim wheels will have reduced the leverage available to pilots trying to use manual trim. Wouldn't we expect this to come under the spotlight as FAA, EASA et al look at what's needed to get the MAX back in the air?
 
OldAeroGuy
Posts: 3921
Joined: Sun Dec 05, 2004 6:50 am

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 1:46 am

asdf wrote:

i am not an aviation engineer
but every time I speak to some they tell me that it is not the right way to build a transport category aircraft with the center of drag not at the center of gravity

no one did that befor (ok, let the Concorde out of that play)

but well
what do I know ....


I've participated in four Part 25 airplane certifications with roles ranging from aerodynamics engineer to Certification chief engineer.

I've never heard of a Part 25 airplane where the center of drag was required to be at the center of gravity. Do you have a source for this requirement?
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
OldAeroGuy
Posts: 3921
Joined: Sun Dec 05, 2004 6:50 am

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 1:58 am

zeke wrote:
OldAeroGuy wrote:
I was planning on writing more on the topic but I'm not sure it would help since you're sure of where you stand. You've stated the 737 MAX will not be re-certified.

In Reply 5569, I've stated what EASA will require to re-certify the 737 Max. Let's see who has the best prediction for 737 MAX history.


Not sure if recertification is the best term to use, the TC is still valid. The FAA issued an emergency order of prohibition, once the technical review is completed that order will be rescinded and the aircraft type can be flown again without recertification.


Fair enough, I was using the term as so many in the forum have expressed a belief that EASA and other agencies will invalidate their original 737 MAX Certifications.

I should have been more precise, words do matter.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
FlyBitcoin
Posts: 96
Joined: Tue Nov 06, 2018 3:38 am

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 2:03 am

SheikhDjibouti wrote:
Unfortunately the world is too often fed lazy interpretations of statistics such as all of the above.
For instance, most hull losses occur on or near the runway, often without fatalities.
We should be able to park these two MAX crashes as something that happened with MAX v1.0 (feat MCAS v1.0!)
Entirely regrettable, and Boeing will quite rightly pay a heavy price for that.

NeoMAX v2.0, (or whatever the new variant is called) should start with a clean slate. Or at least, the generic 737 (all versions) accident rate.

With one single caveat; if NeoMAX v2.0 also encounters problems that can be traced back to MCAS, or lack of sim training, or lack of authority on either the trim wheel or the thumb switches, or anything else that was a contributory factor in JT610 or ET302, then we should pile on the previous two crashes.

Aside from that, there has got to be reasonableness.
Hull losses from heavy landings, windshear on final approach, runway excursions, or suicidal pilots, are all things that could happen to any type.
Whether the greedy headline-seeking media at large will abide by this noble concept is another matter.
We here on a.net should be better than that.


Great post.
At this date, your "one single caveat" above is not trivial in the eyes of many aviation insiders and the flying public. It weighs on this aircraft for some time to come. And as long as these planes fly with MCAS 2.0 before the final reports on the two fatal crashes, then most people will not wipe the slate clean since it is truly unknown what else may have contributed. All flights prior to the final crash reports would be "double probation" for the MAX. And if no other issues are found in the final crash reports, then the plane would still be on "probation" in the eyes of many for a period of time. Perhaps not the amount of time to normalize the prior loss of life statistics, but something in between.

And that one single caveat is why Boeing needs to choose the fix that fully satisfies every country and every customer without question or objection. If that means sim training, then so be it. If it means other changes beyond MCAS and the data input sensors, then Boeing needs to do it. I think Boeing will get this right, but the process of watching them push a fix forward and have the FAA make a statement on it this week, only to hear blowback from aviation bodies and customers in public makes me think they need to do a lot more communication with these agencies and customers in private. Then when consensus is reached, announce the fix and begin the review process with the FAA and other agencies.
 
JHwk
Posts: 577
Joined: Wed Jan 30, 2013 2:11 am

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 2:15 am

After 113 pages of posts, I still find myself unclear on two items:
-Is the stick shaker at takeoff a red herring, or could it be a sign of more significant problems with the plane (fundamentally, or at the time of takeoff for those particular aircraft)?
-At one point in the discussion, mention was made of the AoA sensor value being out of range, and potentially related to a bus voltage issue. Are both AoA sensors supplied from the same bus?

I really wish we could forego the political portions of the debate... everything has been said already far too many times.
 
OldAeroGuy
Posts: 3921
Joined: Sun Dec 05, 2004 6:50 am

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 2:29 am

WPIAeroGuy wrote:
I've tried to explain many times in multiple threads how this could have happened. Instead of trying to understand how a design like this could have been implemented, you'd rather use your benefit of hindsight to disparage a decision making process of which you have zero insight to.

I was not part of this process either, but I'm going to speculate on why the initial FMEA concluded that one AoA sensor was acceptable: MCAS was required to meet certification requirements, but the aircraft could still be flown safely without it. Therefore, rather than add redundant inputs (which you would if it was imperative the system remain operating), the engineers chose to have a fail-safe cutout (cut power to the electric trim motors) in the event of a malfunction, which they (incorrectly) assumed would be identified as a runaway trim problem.


Yes, I think your analysis is correct.

I also suspect they considered the service history of AoA vane signal failures. Vane signal failures are typically in the "Extremely Remote/Rarely" categories. AoA vane service history is why airplane FMEA's have unannuciated stalls in the "Extremely Improbable/Unlikely but not Impossible" category. If MAX AoA vane performance matched that of the NG, an MCAS incident due to a vane signal failure would be as infrequent as any other "STAB Runaway" event, even with only a single vane trigger..

MAX AoA vane service experience is a sharp departure from past airplanes. If ET302 did have a bird strike, it could be chance but it's still disturbing.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
AvFanNJ
Posts: 42
Joined: Tue Mar 12, 2019 9:47 pm

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 2:57 am

Interested wrote:
Definition of safety engineering:

Safety engineering is the process of design o prevent accidents. Engineering Safety Concepts provide detailed approaches and modes for accident reduction by using a risk management process to identify and "design out" hazards.

Do Boeing employ "unsafety engineers"?

They've managed to "design" (I use the word loosely) a plane that "designs in" hazards

How is that possible in this day and age

They wanted a more fuel efficient plane and this is their answer?

Unacceptable. This design should never have got past the drawing board stage. It should have been rejected before any engines even got moved etc.

It's a shambolic design

Why don't you give it a rest and stick to clear facts; we're not interested in your hyperbolic rhetoric which pushes a clearly anti-Boeing agenda of half truths and over the top op-editorializing. Nobody denies Boeing screwed up royally but some of the nonsense I've heard on these threads vilifying the basic 737 design and Boeing's intent is beyond the Pale. And you're one of the worst offenders so why don't you just step back and stick to reality instead of inventing colorful new metaphors to describe a design and a company you clearly have it in for. "Shambolic design", my eye. A relatively light update of a prior design with a relatively stellar safety record is suddenly an unacceptable mess from top to bottom? NO! There are weaknesses in flight control software and sensor input which are now being addressed, along with finally, the proper training materials. A grievous error on Boeing's part, bowing to cost considerations and certification time pressures but NO evident intent to build a death-trap. Even Airbus realizes this but sadly, a number of members in here. We should only stick to what's known for certain and stop lambasting a design process we've no real inside knowledge of. Okay, sir?
 
zoom321
Posts: 46
Joined: Sat Mar 09, 2019 3:05 pm

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 3:05 am

tealnz wrote:

Count me as one more who's puzzled why we're not hearing more about manual trim and electric trim malfunction scenarios. I think it's been established that ability to adjust stabiliser using manual trim wheels was part of the basis on which MAX was given certification. Inability to use manual trim may have been a factor in the ET crash. We've been told that the change to smaller trim wheels will have reduced the leverage available to pilots trying to use manual trim. Wouldn't we expect this to come under the spotlight as FAA, EASA et al look at what's needed to get the MAX back in the air?


IF they look into the manual trim and electric trim malfunction scenarios which they DEFINITELY SHOULD, especially after the Mentour Pilot youtube, wouldn't that affect NGs too ? Not good for B.........
 
User avatar
767333ER
Posts: 1170
Joined: Wed Jun 15, 2016 5:14 am

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 3:41 am

AvFanNJ wrote:
Interested wrote:
Definition of safety engineering:

Safety engineering is the process of design o prevent accidents. Engineering Safety Concepts provide detailed approaches and modes for accident reduction by using a risk management process to identify and "design out" hazards.

Do Boeing employ "unsafety engineers"?

They've managed to "design" (I use the word loosely) a plane that "designs in" hazards

How is that possible in this day and age

They wanted a more fuel efficient plane and this is their answer?

Unacceptable. This design should never have got past the drawing board stage. It should have been rejected before any engines even got moved etc.

It's a shambolic design

Why don't you give it a rest and stick to clear facts; we're not interested in your hyperbolic rhetoric which pushes a clearly anti-Boeing agenda of half truths and over the top op-editorializing. Nobody denies Boeing screwed up royally but some of the nonsense I've heard on these threads vilifying the basic 737 design and Boeing's intent is beyond the Pale. And you're one of the worst offenders so why don't you just step back and stick to reality instead of inventing colorful new metaphors to describe a design and a company you clearly have it in for. "Shambolic design", my eye. A relatively light update of a prior design with a relatively stellar safety record is suddenly an unacceptable mess from top to bottom? NO! There are weaknesses in flight control software and sensor input which are now being addressed, along with finally, the proper training materials. A grievous error on Boeing's part, bowing to cost considerations and certification time pressures but NO evident intent to build a death-trap. Even Airbus realizes this but sadly, a number of members in here. We should only stick to what's known for certain and stop lambasting a design process we've no real inside knowledge of. Okay, sir?

Well the thing is it’s 2019 and we’re on to printing metal objects in a printer, building “smart” cities, and apparently aren’t too far away from a cancer vaccine and yet Boeing can’t even design a simple piece of 1980s software right and any excuse is not good enough especially since over 300 people got killed. Sure they probably didn’t fully realize what cutting some seemingly harmless corners would do, but negligence of a law is never an excuse in court, nor should it be an excuse here. As an engineering firm it is their job to engineer something that is as close to perfect as possible, that can be hard when they are engineering on the bleeding edge of technology, but the 737 is the farthest thing from bleeding edge so they failed miserably and should be held accountable.

We do have insight into the design process, a lot actually if you bother to research. The 737 was going to be discontinued after the NG, but facing pressure from the updated A320 they felt they had to do the MAX. Then they were facing pressure from airlines like Southwest to change as little as possible so that they could save a few bucks which ended up with a plane nearly 40% different than the NG but with the requirement to keep all the cockpit training the same minus a small iPad training course so of course things were left out of the manuals and training and engineering corners we cut and people died. Sounds like corporate greed to me and not just from Boeing, so yeah shambolic.
Been on: 732 733 734 73G 738 752 763 A319 A320 A321 CRJ CR7 CRA/CR9 E145 E175 E190 F28 MD-82 MD-83 C172R C172S P2006T PA-28-180

2 ears for spatial hearing, 2 eyes for depth perception, 2 ears for balance... How did Boeing think 1 sensor was good enough?!
 
planecane
Posts: 1559
Joined: Thu Feb 09, 2017 4:58 pm

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 3:45 am

zoom321 wrote:
tealnz wrote:

Count me as one more who's puzzled why we're not hearing more about manual trim and electric trim malfunction scenarios. I think it's been established that ability to adjust stabiliser using manual trim wheels was part of the basis on which MAX was given certification. Inability to use manual trim may have been a factor in the ET crash. We've been told that the change to smaller trim wheels will have reduced the leverage available to pilots trying to use manual trim. Wouldn't we expect this to come under the spotlight as FAA, EASA et al look at what's needed to get the MAX back in the air?


IF they look into the manual trim and electric trim malfunction scenarios which they DEFINITELY SHOULD, especially after the Mentour Pilot youtube, wouldn't that affect NGs too ? Not good for B.........

The manual trim wheel is fine if the aircraft is close to being in trim. The runaway stabilizer procedure (pre MCAS update) said to use the electric trim to balance control forces before switching the cutoff switches. The wheel with then be used to adjust trim.

The scenario of a stabilizer runaway that requires the trim wheel drive a situation where the plane is severely out of trim would be extremely unlikely.

In the one in a billion case, the "roller coaster" procedure can be used. Mentour Pilot mentioned in one of his videos that this is still in the FCOM and he knew shit it c
 
User avatar
hOMSaR
Moderator
Posts: 2338
Joined: Tue Jan 19, 2010 4:47 am

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 3:53 am

par13del wrote:
Ok, so Boeing's stock tanks, then what, they use the dreaded Chpt.11 to clear pensions, union contracts, other debt, re-organize then start selling all their a/c at even greater give away prices, and the aviation industry is better because they start increasing their market share by selling a/c at prices Airbus cannot compete?


That’s not how any of that works.
I was raised by a cup of coffee.
 
ArgentoSystems
Posts: 315
Joined: Sun Mar 24, 2019 12:05 am

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 4:20 am

par13del wrote:
Ok, so Boeing's stock tanks, then what, they use the dreaded Chpt.11 to clear pensions, union contracts, other debt, re-organize then start selling all their a/c at even greater give away prices, and the aviation industry is better because they start increasing their market share by selling a/c at prices Airbus cannot compete?


Oh please that is just absurd. For starters, stock tanking does not influence company's ability to operate. Second, even if MAX is prohibited to fly forever, and they have to spend another 10 years developing a new plane, they would still not go bankrupt.
 
Interested
Posts: 887
Joined: Thu May 19, 2016 12:19 pm

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 5:34 am

AvFanNJ wrote:
Interested wrote:
Definition of safety engineering:

Safety engineering is the process of design o prevent accidents. Engineering Safety Concepts provide detailed approaches and modes for accident reduction by using a risk management process to identify and "design out" hazards.

Do Boeing employ "unsafety engineers"?

They've managed to "design" (I use the word loosely) a plane that "designs in" hazards

How is that possible in this day and age

They wanted a more fuel efficient plane and this is their answer?

Unacceptable. This design should never have got past the drawing board stage. It should have been rejected before any engines even got moved etc.

It's a shambolic design

Why don't you give it a rest and stick to clear facts; we're not interested in your hyperbolic rhetoric which pushes a clearly anti-Boeing agenda of half truths and over the top op-editorializing. Nobody denies Boeing screwed up royally but some of the nonsense I've heard on these threads vilifying the basic 737 design and Boeing's intent is beyond the Pale. And you're one of the worst offenders so why don't you just step back and stick to reality instead of inventing colorful new metaphors to describe a design and a company you clearly have it in for. "Shambolic design", my eye. A relatively light update of a prior design with a relatively stellar safety record is suddenly an unacceptable mess from top to bottom? NO! There are weaknesses in flight control software and sensor input which are now being addressed, along with finally, the proper training materials. A grievous error on Boeing's part, bowing to cost considerations and certification time pressures but NO evident intent to build a death-trap. Even Airbus realizes this but sadly, a number of members in here. We should only stick to what's known for certain and stop lambasting a design process we've no real inside knowledge of. Okay, sir?


I stand by every word I've posted. Shambolic design from the start that should never have got past the drawing board. And I guarantee behind closed doors there will be people at Boeing incredulous at how they got themselves into this sad and sorry position. They are in a huge mess now. Boeing know they've messed up big time. They just can't say it.

Despite the fact many of the mistakes came about as a result of financial greed - this episode is going to prove to be by far the biggest financial mistake in Boeings history to date. So much income depends on this plane.

I've woken up to read in the news that 8 countries plus Europe plus 3 agencies are together looking at how this plane ever got certified in the first place. This is separate to what Boeing and FAA are working on to get the plane re-certified.

It's a terrible hardware design that software is now having to try and fix. When in fact it's the hardware that needs fixing.

I'm sorry - much as Boeing and Boeing supporters on here would love to wave a magic wand and make all these problems go away it's simply not going to happen. Too much scrutiny. Too many mistakes. A rush to introduce a more fuel efficient plane that failed to account for the safety of the passengers who would have to fly on it.

ShambolIc.
Last edited by Interested on Sat Apr 20, 2019 6:01 am, edited 2 times in total.
 
Interested
Posts: 887
Joined: Thu May 19, 2016 12:19 pm

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 5:50 am

This article re-enforces that with such poor hardware design there's only so much that software patches can do to help this plane:

https://www.zdnet.com/article/boeing-73 ... o-so-much/
 
User avatar
Francoflier
Posts: 5267
Joined: Wed Oct 31, 2001 12:27 pm

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 6:20 am

OldAeroGuy wrote:
Yes, the other 5 modes can bring the plane down if the pilots do not recognize "STAB Runaway" and apply the appropriate procedures. It's worth noting that none of these 5 are called out specifically in the 737 QRH. They are all covered under a single "STAB Runaway" procedure.


Is there a function that alerts the pilots of a stab runaway condition on the 737NG/MAX?
Other versions of Boeing aircraft do, through EICAS message, which triggers the procedure, so I was wondering whether this would also be the case for the 737.

In any case, 'silent' stab runaway is not easy to detect, especially in a high workload scenario, and much less if the A/P is on, at least until it is too late. MCAS activation would not be communicated to the pilots which adds another layer of complexity: they now have to understand that MCAS is activating and then try to figure out whether the activation is genuine or erroneous. Even if it is erroneous, it would not necessarily qualify as a stab 'runaway' as it is not, in fact, 'running away'.
By the same metric, I can't imagine a foolproof syatem that would allow to warn of an erroneous MCAS activation, other than the partial protection of the AoA disagree, which does not cover all bases.

Many on here try to classify spurious MCAS activation as a 'stab runaway' condition, and I vehemently disagree, especially given the possibility of erroneous speed indication given to the pilots, as appears to have been the case for JT at least.
Pilots have been taught to trust airspeed less than attitude and AoA indications, especially after AF447.
I wouldn't blame a pilot with essentially no understanding of MCAS (as was the case until recently) to trust his stall warning more than his airspeed. Spurious MCAS activation might only add to the confusion by seeming genuine.

I'm not saying it's your case, but I quite dislike those who simply throw MCAS misbehavior into the 'stab runaway' bin as if it was as easy as that.
I'll do my own airline. With Blackjack. And hookers. In fact, forget the airline.
 
Zeppi
Posts: 106
Joined: Mon Aug 08, 2016 8:35 pm

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 6:50 am

Interesting summary on Boeing's corporate culture and cost/corner cutting by a former employee https://old.reddit.com/r/videos/comments/bdfqm4/the_real_reason_boeings_new_plane_crashed_twice/ekyyd9g/.
Of course no way to verify, just thought it would fit into this topic as more an more evidence seems to point this way.

Looks like the old slogan needs some rework too: If it's Boeing, I ain't going.

Such a shame that a company that used to be held high by producing quality aircraft seems to have deteriorated into yet another case of corporate greed taking over.
 
Interested
Posts: 887
Joined: Thu May 19, 2016 12:19 pm

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 7:06 am

Zeppi wrote:
Interesting summary on Boeing's corporate culture and cost/corner cutting by a former employee https://old.reddit.com/r/videos/comments/bdfqm4/the_real_reason_boeings_new_plane_crashed_twice/ekyyd9g/.
Of course no way to verify, just thought it would fit into this topic as more an more evidence seems to point this way.

Looks like the old slogan needs some rework too: If it's Boeing, I ain't going.

Such a shame that a company that used to be held high by producing quality aircraft seems to have deteriorated into yet another case of corporate greed taking over.


It's too detailed to be made up

It's not a reflection of Boeing it's a reflection or large organisations full stop
 
flybucky
Posts: 376
Joined: Tue Apr 17, 2018 7:44 pm

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 7:30 am

SANChaser wrote:
Here's an article on ieee.org (for those not in software/EE, a very respected outfit :) ). I found it to be quite comprehensive and detailed, from a systems engineering and software point of view.
https://spectrum.ieee.org/aerospace/aviation/how-the-boeing-737-max-disaster-looks-to-a-software-developer

I haven't had the chance to read that article in detail yet. Peter Lemme's response: "This article has so many errors I can’t even start to offer help. shame on ⁦@IEEESpectrum⁩ for publishing this. Do a little fact checking next time."
https://twitter.com/Satcom_Guru/status/ ... 4224343044

Like I said, I haven't read the article in detail myself yet. Just posting a counterpoint from another expert.
 
User avatar
scbriml
Posts: 19038
Joined: Wed Jul 02, 2003 10:37 pm

Re: B737MAX Grounded Worldwide

Sat Apr 20, 2019 7:42 am

Interested wrote:
It's not a reflection of Boeing it's a reflection or large organisations full stop


I worked for a global American corporation for the best part of 34 years. They were never, ever the way Boeing is described in that article. Never. Your brush is too broad.
Time flies like an arrow. Fruit flies like a banana!
There are 10 types of people in the World - those that understand binary and those that don't.

Popular Searches On Airliners.net

Top Photos of Last:   24 Hours  •  48 Hours  •  7 Days  •  30 Days  •  180 Days  •  365 Days  •  All Time

Military Aircraft Every type from fighters to helicopters from air forces around the globe

Classic Airliners Props and jets from the good old days

Flight Decks Views from inside the cockpit

Aircraft Cabins Passenger cabin shots showing seat arrangements as well as cargo aircraft interior

Cargo Aircraft Pictures of great freighter aircraft

Government Aircraft Aircraft flying government officials

Helicopters Our large helicopter section. Both military and civil versions

Blimps / Airships Everything from the Goodyear blimp to the Zeppelin

Night Photos Beautiful shots taken while the sun is below the horizon

Accidents Accident, incident and crash related photos

Air to Air Photos taken by airborne photographers of airborne aircraft

Special Paint Schemes Aircraft painted in beautiful and original liveries

Airport Overviews Airport overviews from the air or ground

Tails and Winglets Tail and Winglet closeups with beautiful airline logos