On Sunday, 21 April 2019 at 19:52:58 UTC, Walter Bright wrote:

>
> I have my beefs with the article.
>
> For example,
>
> "They want to have one airplane that all their pilots can fly because that makes both pilots and airplanes fungible, maximizing flexibility and minimizing costs."
>
> Safety is a factor in having different airplanes fly the same. Many accidents have occurred because the pilot, in a moment of stress, applied a solution that would have been correct on the aircraft type he had more experience on.

Safety being a factor in making planes fly the same doesn't remove cost as a factor in Boeing not making the MCAS well-known and not requiring that pilots learn about and be trained on the "sequence" that was necessary to override MCAS. But there are claims that the Ethiopian pilots did go through that sequence more than once, suggesting that any override was temporary and futile. But there are other reports that the Indonesian airliner that crashed had had an off-duty pilot riding shotgun who knew the "disable sequence" and successfully disabled the faulty MCAS system the day before the fatal crash.


> He argues that airplanes are stable without augmentation. This isn't true for any jetliners, they have an active yaw damper:

I don't know which part you are referring to as suggesting "are stable without augmentation" (a phrase not in the article), but I see him saying "The airframe, the hardware, should get it right the first time and not need a lot of added bells and whistles to fly predictably". I don't read that as planes should have "zero pilot augmentation". I think his point is you don't design an aircraft, and when you find it has a tendency to stall on takeoff more than a typical or historical aircraft, go ahead and produce it anyway. "Other than a higher than normal tendency to stall on takeoff..." is not what most people want to hear in a design review of a proposed production aircraft.

On Sunday, 21 April 2019 at 19:52:58 UTC, Walter Bright wrote:
> On 4/21/2019 10:18 AM, Paolo Invernizzi wrote:
>> I'm finding this article [1] amazing, looking at all the anecdotical stories that Walter has told us during all that 15 years regarding engineering in avionic industry.
>> 
>> Without specifically discussing the Boing case, but looking at industry in general...
>> Really, things will go horribly wrong, before starting to go better again?
>> 
>> Happy Easter to everybody!
>> 
>> [1] https://spectrum.ieee.org/aerospace/aviation/how-the-boeing-737-max-disaster-looks-to-a-software-developer
>
> I have my beefs with the article.
>
> For example,
>
> "They want to have one airplane that all their pilots can fly because that makes both pilots and airplanes fungible, maximizing flexibility and minimizing costs."
>
> Safety is a factor in having different airplanes fly the same. Many accidents have occurred because the pilot, in a moment of stress, applied a solution that would have been correct on the aircraft type he had more experience on.

You can't have two planes fly the same, if they did they wouldn't be different then. You could say there's risk factor in that you try and do something with one plane, it is so similar for that one minuet difference that could cause an accident cause the pilot thinks it is doing something else.

There have also been incidents where the pilot was because in a moment of stress he applied a solution from another aircraft to the aircraft he was flying. A technique used by gliders, a single/two seater aircraft that has no engines, was applied to a boeing 767.

> He argues that airplanes are stable without augmentation. This isn't true for any jetliners, they have an active yaw damper:
>
>   https://en.wikipedia.org/wiki/Dutch_roll
>
> In particular:
>
>   https://en.wikipedia.org/wiki/Dutch_roll#Accidents
>
>
> He argues that it would be safer to develop a whole new airframe. Any new airframe, by definition, will be an unproven design, and everything in it would need to be re-proven, which has its limits.
>
>
> "Neither such coders nor their managers are as in touch with the particular culture and mores of the aviation world as much as the people who are down on the factory floor, riveting wings on, designing control yokes, and fitting landing gears. Those people have decades of institutional memory about what has worked in the past and what has not worked. Software people do not."
>
> This is sheer nonsense. People on the shop floor assembling airplanes do indeed have institutional knowledge about what works in manufacturing. They have no idea what works when flying or various failure modes. They have zero experience with stability issues. They do not do design work. Even more ignorant, the 757 I worked on back in 1980 had many computer systems that controlled the airplane, such as the autopilot. Last I checked that was 4 decades ago, and software programmers and managers implemented it.
>
>
> Boeing did indeed make mistakes with the MCAS software design. I won't defend that, I don't understand the causes of those mistakes. But it wasn't about cost saving, another scurrilous charge by the author. The fact that the fix is a software update is evidence enough that it was a mistake, not some blind greed.

A mistake that could have been caught with more rigorous testing and training. From what I understand the pilots received an hour long training session about the new plane on an ipad and that was it. I wouldn't be surprised if they cut corners and costs by not testing and providing enough training. I wouldn't be surprised if they did cut costs with testing, it's something that will eat a good chunk of costs with very little benefit, unless something goes wrong, like it has. I'm skeptical that a software patch will solve all these issue. I don't have the confidence you have in these companies. Maybe they were different 40 years ago. It's easy to say, all problems that were being experienced by our aircraft were fixed with a software patch. Hope they keep these planes grounded until they actually make sure they are safe and do actual runs with the plane without any passengers on it so they don't all crash and burn.

> There's more, but I should stop here. I'm just tired of these hit pieces from people who only partially know what they're talking about. I'll fly in a 737Max any day.

We'll see if any country ever allows it to fly again. There's a long list of countries that have grounded the plane.

On Sunday, 21 April 2019 at 19:52:58 UTC, Walter Bright wrote:
> On 4/21/2019 10:18 AM, Paolo Invernizzi wrote:
>>[snip]
> I have my beefs with the article.
>
> For example,
>
> "They want to have one airplane that all their pilots can fly because that makes both pilots and airplanes fungible, maximizing flexibility and minimizing costs."
>
> Safety is a factor in having different airplanes fly the same. Many accidents have occurred because the pilot, in a moment of stress, applied a solution that would have been correct on the aircraft type he had more experience on.
>
>
> He argues that airplanes are stable without augmentation. This isn't true for any jetliners, they have an active yaw damper:
>
>   https://en.wikipedia.org/wiki/Dutch_roll
>
> In particular:
>
>   https://en.wikipedia.org/wiki/Dutch_roll#Accidents
>
>
> He argues that it would be safer to develop a whole new airframe. Any new airframe, by definition, will be an unproven design, and everything in it would need to be re-proven, which has its limits.

I think the point there was that the practical "evolutions" that could be done to the 737's airframe was done, so Boeing pretty much had to make a new airframe if they wanted to compete in the same market. I'm not an expert so I can't comment on the validity of this claim. However, I can say that the idea that a plane can leave safe controlled flight and pitch up at extreme rates, when the thrust is at max, is not something that should be an acceptable trade-off.


> "Neither such coders nor their managers are as in touch with the particular culture and mores of the aviation world as much as the people who are down on the factory floor, riveting wings on, designing control yokes, and fitting landing gears. Those people have decades of institutional memory about what has worked in the past and what has not worked. Software people do not."
>
> This is sheer nonsense. People on the shop floor assembling airplanes do indeed have institutional knowledge about what works in manufacturing. They have no idea what works when flying or various failure modes. They have zero experience with stability issues. They do not do design work. Even more ignorant, the 757 I worked on back in 1980 had many computer systems that controlled the airplane, such as the autopilot. Last I checked that was 4 decades ago, and software programmers and managers implemented it.
>
>
> Boeing did indeed make mistakes with the MCAS software design. I won't defend that, I don't understand the causes of those mistakes. But it wasn't about cost saving, another scurrilous charge by the author. The fact that the fix is a software update is evidence enough that it was a mistake, not some blind greed.

Ypu need to see more than just the failure of the design of the MCAS. From many media reports, its been said that the pilots were taught that this is the same plane. That was a selling point. No need for re certifying pilots. However the plane behaves differently enough from previous planes that this is demonstrably false. Also the MCAS seems to be a "prevent the plane from crashing, *after* stall like conditions have been detected", as opposed to "make the plane fly like the previous 737 generation".

To recap:
- Boeing fails to tell pilots what can happen under certain situations (specifically thrust increase results in higher than acceptable pitch up)
- Boeing fails to train pilots about what to do with regards to MCAS when the system makes incorrect inputs
- Boeing makes MCAS with poor design decisions that never should have made it onto a production commercial airliner.

> Absent from his article is anything about Airbus. Airbus has had crashes due to avionics software problems, too.

Its not just avionics problems. Many planes have suffered from avionics. Its the surrounding corporate negligence, and the incredibly bad design of the MCAS that make this incident important.

> The author is a pilot, but has never flown airliners and has no experience with them.
>
> There's more, but I should stop here. I'm just tired of these hit pieces from people who only partially know what they're talking about. I'll fly in a 737Max any day.

I'm sure you wouln't fly in one until the fix has been published and the pilots have been trained.

On 4/21/2019 10:54 PM, Uknown wrote:
> I'm sure you wouln't fly in one until the fix has been published and the pilots have been trained.

Actually, I would even in an unmodified 737MAX. The reason is that the way to deal with it, even if pilots don't know about it, is to follow their training for runaway stab trim. This is what the pilots did in the first Lion Air incident, and they landed without incident. In the second LA incident, and in the Ethiopian one, they did not and crashed.

It's simple:

1. The electric trim switches on the control column override the MCAS commands.

2. When trimmed, shut off the stab trim with the cutoff switches on the console.

Both pilots in the crashes were performing (1). The mystery to me is why they did not continue to do it, then perform (2). We'll have to wait for the NTSB report which hopefully can explain that.

I would expect with all this publicity even an incompetent pilot would be able to accomplish this.

BTW, I only saw one article publish (1) and (2). (The wording is from memory, I don't recall the exact words in the Boeing instructions.) All the other articles leave it out and prefer to publish hysterical clickbait articles.

Boeing still needs to fix the MCAS system, because how airplanes are made robust is to fix every point in the string of failures that led to a crash.

BTW, I was a nervous flyer before I worked at Boeing on flight control systems. Knowing how things actually worked and how things were built changed it all for me. An awful lot about what is written in newspapers about technical airplane issues is complete trash. Journalists don't know **** about airplanes, and they garble it all up. If you want the straight dope, read the NTSB incident reports.

The pilot's article linked to sounds authoritative, until one notices he's not an airline pilot, and (for instance) does not realize that all swept wing airplanes are fundamentally unstable, and that Rosie the Riveter knows nothing about stability issues.

You don't need to believe anything I say - so I recommend withholding judgement until the NTSB report(s) come out. You'll learn a lot reading them. The NTSB does a good job thoroughly stating the facts and leaving off the hysteria.

On Monday, 22 April 2019 at 20:35:31 UTC, Walter Bright wrote:
> On 4/21/2019 10:54 PM, Uknown wrote:
>> [snip]
>
> Actually, I would even in an unmodified 737MAX. The reason is that the way to deal with it, even if pilots don't know about it, is to follow their training for runaway stab trim. This is what the pilots did in the first Lion Air incident, and they landed without incident. In the second LA incident, and in the Ethiopian one, they did not and crashed.
>
> It's simple:
>
> 1. The electric trim switches on the control column override the MCAS commands.
>
> 2. When trimmed, shut off the stab trim with the cutoff switches on the console.
>

Yes, and what you said is inline with what Boeing said after they the Ethiopian airline crash :

> In the event an uncommanded nose down stabilizer trim is experienced on the 737 - 8 / - 9, in conjunction with one or more of the above indications or effects, do the Runaway Stabilizer NNC ensuring that the STAB TRIM CUTOUT switches are set to CUTOUT and stay in the CUTOUT position for the remainder of the flight.

> Both pilots in the crashes were performing (1). The mystery to me is why they did not continue to do it, then perform (2). We'll have to wait for the NTSB report which hopefully can explain that.

I read an ars technica piece that said that they performed (1), however the MCAS they did something else that brought back the MCAS system and at this point it was too late to recover. However I would rather wait for some official report in this one.

> I would expect with all this publicity even an incompetent pilot would be able to accomplish this.
>
> BTW, I only saw one article publish (1) and (2). (The wording is from memory, I don't recall the exact words in the Boeing instructions.) All the other articles leave it out and prefer to publish hysterical clickbait articles.

https://arstechnica.com/information-technology/2018/11/indonesia-737-crash-caused-by-safety-feature-change-pilots-werent-told-of/?comments=1

This one does mention it, as a press bulletin at the end. Yes media is trash and will publish clickbait about everything that is remotely technical. They trash every new military project without any knowledge of it (LCA Tejas was late, F-35 is a waste of money, etc.). No point listening to them. However many pilots have complained that they really weren't even aware of the MCAS system, with no prior training being given. That's definitely not a good sign.

> Boeing still needs to fix the MCAS system, because how airplanes are made robust is to fix every point in the string of failures that led to a crash.

Yes, however the question is how did such a poorly designed sytem get approved in the first place?

> BTW, I was a nervous flyer before I worked at Boeing on flight control systems. Knowing how things actually worked and how things were built changed it all for me. An awful lot about what is written in newspapers about technical airplane issues is complete trash. Journalists don't know **** about airplanes, and they garble it all up. If you want the straight dope, read the NTSB incident reports.

How long do they usually take? 4-6 months? I've never been interested in an air crash investigation as much as this one.

> The pilot's article linked to sounds authoritative, until one notices he's not an airline pilot, and (for instance) does not realize that all swept wing airplanes are fundamentally unstable, and that Rosie the Riveter knows nothing about stability issues.

I agree this article is nonsense. The idea that code is somehow "less safe" or just not good enough for aviation is nonsense. I presumed that the rest of the article was true, however you claim otherwise. The only true part seems to be

1. The MCAS was poorly designed
2. The plane pitches up (more than an acceptable degree) when thrust is provided, which is why the MCAS is necessary

> You don't need to believe anything I say - so I recommend withholding judgement until the NTSB report(s) come out. You'll learn a lot reading them. The NTSB does a good job thoroughly stating the facts and leaving off the hysteria.

On Monday, 22 April 2019 at 20:35:31 UTC, Walter Bright wrote:
> On 4/21/2019 10:54 PM, Uknown wrote:
>> I'm sure you wouln't fly in one until the fix has been published and the pilots have been trained.
>
> Actually, I would even in an unmodified 737MAX. The reason is that the way to deal with it, even if pilots don't know about it, is to follow their training for runaway stab trim. This is what the pilots did in the first Lion Air incident, and they landed without incident. In the second LA incident, and in the Ethiopian one, they did not and crashed.
>
> It's simple:
>
> 1. The electric trim switches on the control column override the MCAS commands.
>
> 2. When trimmed, shut off the stab trim with the cutoff switches on the console.
>
> Both pilots in the crashes were performing (1). The mystery to me is why they did not continue to do it, then perform (2). We'll have to wait for the NTSB report which hopefully can explain that.
>
> I would expect with all this publicity even an incompetent pilot would be able to accomplish this.
>
> BTW, I only saw one article publish (1) and (2). (The wording is from memory, I don't recall the exact words in the Boeing instructions.) All the other articles leave it out and prefer to publish hysterical clickbait articles.

Here we are the details, right from Boeing...

http://www.b737.org.uk/mcas.htm


>
> Boeing still needs to fix the MCAS system, because how airplanes are made robust is to fix every point in the string of failures that led to a crash.
>
> BTW, I was a nervous flyer before I worked at Boeing on flight control systems. Knowing how things actually worked and how things were built changed it all for me. An awful lot about what is written in newspapers about technical airplane issues is complete trash. Journalists don't know **** about airplanes, and they garble it all up. If you want the straight dope, read the NTSB incident reports.

That's what usually I do, but the point is another... see below...

> The pilot's article linked to sounds authoritative, until one notices he's not an airline pilot, and (for instance) does not realize that all swept wing airplanes are fundamentally unstable, and that Rosie the Riveter knows nothing about stability issues.
>
> You don't need to believe anything I say - so I recommend withholding judgement until the NTSB report(s) come out. You'll learn a lot reading them. The NTSB does a good job thoroughly stating the facts and leaving off the hysteria.

And that's fine. What I want to discuss, is the last part in the link that I've included in this port, I quote it for convenience:

"""
The Proposed Fix

Boeing have been working on a software modification to MCAS since the Lion Air accident. Unfortunately although originally due for release in January it was not released due to both engineering challenges and differences of opinion among some federal and company safety experts over how extensive the changes should be.
"""

Please note the "engineering challenges" and "differences of opinion". Moreover:

"""
Note that as MCAS is an FCC function, the modifications to MCAS are made in the FCC software. The revision will be known as FCC P12.1

There are three significant changes to MCAS software being worked on by Boeing:

1) To give the system input from both angle-of-attack sensors, Currently MCAS only uses data from the angle of attack sensor on the side of the active FCC, (see AoA source). The system will have split vane monitor and Mid Value Select (MVS) input. This will both enhance detection of erroneous AoA vane behaviour and the MVS signal selection will pick the average of ADIRU L & R and the previous MVS output. If the output of the two AoA vanes differ by more than 5.5 degrees MCAS will be disabled.
"""

So, only one sensor was used: no redundancy, no cross check, no taking in account other inputs to find out anomalies. Taking differences in account, it resembles me something like not having "asserts", or better, throwing 'error' in the codebase ("hey, we CAN'T reconcile that AoA with the current increasing of speed and decreasing of altitude! Assert, abort! throw 'error', abort!)

Moreover:

"""
2) To limit how much MCAS can move the horizontal stab to guarantee sufficient handling capability using elevator alone. In its original report, Boeing said that MCAS could move the horizontal stabilizer a maximum of 0.6 degrees. However, after the Lion Air crash, it told airlines that MCAS could actually move it 2.5 degrees, or half the physical maximum. Boeing reportedly increased the limit because flight tests showed that a more powerful movement was needed at high AoA rather than at high Mach.
"""

Half of the physical maximum! Moreover:

"""
3) A modification to the activation and resynchronisation schedule. MCAS will be limited to operate only for one cycle per high AoA event, rather than multiple. At present it will operate for 10s, pause for 5s and repeat for as often as it senses the high AoA condition is present. Furthermore the logic for MCAS to command a nose up stab trim to return to trim following pilot eletric trim intervention or exceeding the forward column cutout switch, will also now be improved.
"""

What to say?

In my humble opinion, that's the result of "pressure" to have a "solution" for some "not disclosed goal" (hint, the MCAS should be "transparent to pilot", as "that's simply a 737!")

Pressure over engineerings coming from management, I'm meaning (again, personal opinions).

So, here we are back to us: what's the current state of affair in having sloppy designed systems (or sloppy implemented system!) caused by time pressure, management pressure, cost pressure?

I mean, D pushing hard, to be a memory safe language, for example, but it seems that safety and good design are falling down in the list of priorities... no?

On Mon, 2019-04-22 at 13:35 -0700, Walter Bright via Digitalmars-d wrote: […]
> 
> Boeing still needs to fix the MCAS system, because how airplanes are made
> robust
> is to fix every point in the string of failures that led to a crash.
[…]

Surely, Boeing need to remove the MCAS system by reverting the 737 design to be stable rather than unstable.

The 737 MAX is, as far as I know, the first commercial airplane to be unstable. All military fighter airplanes are unstable but that is a military fighter. To date, again as far as I know, the strategy had been that all commercial aircraft were stable. Boeing broke ranks on this strategy with the 737MAX simply because they were trying to put an engine that was too big for the space available and so moved the engine forward and upward creating an aerodynamically unstable configuration.

-- 
Russel.
===========================================
Dr Russel Winder      t: +44 20 7585 2200
41 Buckmaster Road    m: +44 7770 465 077
London SW11 1EN, UK   w: www.russel.org.uk

On Tuesday, 23 April 2019 at 08:06:14 UTC, Paolo Invernizzi wrote:
> The Proposed Fix
>
> Boeing have been working on a software modification to MCAS since the Lion Air accident. Unfortunately although originally due for release in January it was not released due to both engineering challenges and differences of opinion among some federal and company safety experts over how extensive the changes should be.

To me this is incredible. A plane crashes. The manufacturer begins working on a "software modification" as a result of the crash (if they weren't actually working on it all along knowing the design they got approved was bogus), which is actually a bug fix/design fix. Yet the plane is still allowed to fly before the fix is tested and installed and there is also no warning issued to all the airlines letting them know there is a problem that resulted in fatalities and a fix is not yet available - so get thorough training on how to handle an MCAS system failure. And then - knowing they haven't installed their fix - after a second plane crashes and with "don't have the full details yet to know if there is any relationship" as a rationale, the recommendation of the FAA and Boeing is "keep flying 737 MAX 8s".

On Monday, 22 April 2019 at 20:35:31 UTC, Walter Bright wrote:
> On 4/21/2019 10:54 PM, Uknown wrote:
>> [snip]
>
> Actually, I would even in an unmodified 737MAX. The reason is that the way to deal with it, even if pilots don't know about it, is to follow their training for runaway stab trim. This is what the pilots did in the first Lion Air incident, and they landed without incident. In the second LA incident, and in the Ethiopian one, they did not and crashed.
>
> It's simple:
>
> 1. The electric trim switches on the control column override the MCAS commands.
>
> 2. When trimmed, shut off the stab trim with the cutoff switches on the console.
>

Yes, and what you said is inline with what Boeing said after they the Ethiopian airline crash :

> In the event an uncommanded nose down stabilizer trim is experienced on the 737 - 8 / - 9, in conjunction with one or more of the above indications or effects, do the Runaway Stabilizer NNC ensuring that the STAB TRIM CUTOUT switches are set to CUTOUT and stay in the CUTOUT position for the remainder of the flight.

> Both pilots in the crashes were performing (1). The mystery to me is why they did not continue to do it, then perform (2). We'll have to wait for the NTSB report which hopefully can explain that.

I read an ars technica piece that said that they performed (1), however the MCAS they did something else that brought back the MCAS system and at this point it was too late to recover. However I would rather wait for some official report in this one.

> I would expect with all this publicity even an incompetent pilot would be able to accomplish this.
>
> BTW, I only saw one article publish (1) and (2). (The wording is from memory, I don't recall the exact words in the Boeing instructions.) All the other articles leave it out and prefer to publish hysterical clickbait articles.

https://arstechnica.com/information-technology/2018/11/indonesia-737-crash-caused-by-safety-feature-change-pilots-werent-told-of/?comments=1

This one does mention it, as a press bulletin at the end. Yes media is trash and will publish clickbait about everything that is remotely technical. They trash every new military project without any knowledge of it (LCA Tejas was late, F-35 is a waste of money, etc.). No point listening to them. However many pilots have complained that they really weren't even aware of the MCAS system, with no prior training being given. That's definitely not a good sign. And everything points to the fact that the MCAS is poorly designed.

> Boeing still needs to fix the MCAS system, because how airplanes are made robust is to fix every point in the string of failures that led to a crash.

Yes, however the question is: how did such a poorly designed system get approved in the first place?

> [snip] Journalists don't know **** about airplanes,

Journalists generally don't know anything about anything technical, and will report it in a way to increase views/clicks. See also science reporting in general.

> and they garble it all up. If you want the straight dope, read the NTSB incident reports.

How long do they usually take? 4-6 months? I've never been interested in an air crash investigation as much as this one. I'd love to read the official report.

> The pilot's article linked to sounds authoritative, until one notices he's not an airline pilot, and (for instance) does not realize that all swept wing airplanes are fundamentally unstable, and that Rosie the Riveter knows nothing about stability issues.

I agree this article is nonsense. The idea that code is somehow "less safe" or just not good enough for aviation is nonsense. I presumed that the rest of the article was true, however you claim otherwise. The only true part seems to be

1. The MCAS was poorly designed
2. The plane pitches up (more than an acceptable degree) when thrust is provided, which is why the MCAS is necessary.

> You don't need to believe anything I say - so I recommend withholding judgement until the NTSB report(s) come out. You'll learn a lot reading them. The NTSB does a good job thoroughly stating the facts and leaving off the hysteria.

I think most of the stuff wrt relaxed stability in a commercial plane is gibberish. Its OK for a plane to have relaxed stability, as long as it has a properly designed flight system that can keep the plane stable and flying in a controlled manner. I suspect that the report will confirm this, but blast Boeing for doing a poor job designing the MCAS. From what I understand the MD-11 aslo has some degree of relaxed stability.

On Tuesday, 23 April 2019 at 08:09:58 UTC, Russel Winder wrote:
> On Mon, 2019-04-22 at 13:35 -0700, Walter Bright via Digitalmars-d wrote: […]
>> [snip]
> Surely, Boeing need to remove the MCAS system by reverting the 737 design to be stable rather than unstable.
>
> The 737 MAX is, as far as I know, the first commercial airplane to be unstable.

The McDonal Douglass MD-11 was also unstable and was used for freight transport.

Wiki link : https://en.wikipedia.org/wiki/McDonnell_Douglas_MD-11

It was designed to have a smaller stabiliser, to reduce drag and thus improve fuel efficiency.

> All military fighter airplanes are unstable but that is a military fighter. To date, again as far as I know, the strategy had been that all commercial aircraft were stable. Boeing broke ranks on this strategy with the 737MAX simply because they were trying to put an engine that was too big for the space available and so moved the engine forward and upward creating an aerodynamically unstable configuration.

Not all are, the ones that are unstable are generally designed in that way so that they are more manoeuvrable. They use use digital fly by wire to make sure that the plane is seemingly stable. This decision by Boeing would have been fine if they had designed their software properly.