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Stitch
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Re: Boeing 737MAX Grounding, General Discussion Thread, May 2020

Thu Jun 11, 2020 5:40 pm

hiflyeras wrote:
This cannot be good news...fuselage production stopped. A major change needing to be made?


I would not be surprised if this is a reflection that customers have informed Boeing their MAX intake will be lower than planned due to the current slowdown and Boeing may have enough produced frames "on hand" for each customer ready and able to take deliveries once the Airworthiness Certificate has been restored to meet that demand so they don't want to build even more frames they have to then find some place to park and possibly end up having to re-work for a new customer.
 
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Re: Boeing 737MAX Grounding, General Discussion Thread, May 2020

Thu Jun 11, 2020 7:04 pm

Stitch wrote:
hiflyeras wrote:
This cannot be good news...fuselage production stopped. A major change needing to be made?


I would not be surprised if this is a reflection that customers have informed Boeing their MAX intake will be lower than planned due to the current slowdown and Boeing may have enough produced frames "on hand" for each customer ready and able to take deliveries once the Airworthiness Certificate has been restored to meet that demand so they don't want to build even more frames they have to then find some place to park and possibly end up having to re-work for a new customer.


Not to mention the inventory of 100+ fuselages already built by Spirit (and paid for by Boeing), but not yet delivered to Renton.
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Re: Boeing 737MAX Grounding, General Discussion Thread, May 2020

Fri Jun 12, 2020 5:08 am

 
oschkosch
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Re: Boeing 737MAX Grounding, General Discussion Thread, May 2020

Fri Jun 12, 2020 6:26 am

Here's an interesting article! Mopping up bits and pieces: probably bits and bytes too! And some tests scheduled for May just didn't happen...

https://theaircurrent.com/aviation-safe ... ts-return/

737 Max software done, but regulators plot more changes after jet's return


While a clear path to re-certification has emerged, those close to the process caution that there are still potential pitfalls that may extend the multinational process for re-approving the Boeing jet again for service after it was grounded in March 2019 after two crashes killed 346 people.<

Two industry officials close to the recertification and re-entry of the 737 Max caution that a late June certification test flight is possible, but other milestones including ones once planned for May have not yet taken place. Two publications, both reported June 11 that Boeing and the Federal Aviation Administration could fly a formal certification sortie by month’s end.

Once the flight is complete, the FAA and other regulators will be able to hold the Joint Operations Evaluation Board (JOEB) review to determine the final training requirements for flying the 737 Max. FAA Administrator Steve Dickson outlined to The Air Current the final steps in February to returning the jet to service. In advance of the JOEB, which has not yet been scheduled, Boeing earlier this week sent an Operators Memo to 737 Max airlines outlining the draft training changes for pilots along with a service bulletin for modifying the jet’s wiring.

Crucially, Boeing and Collins Aerospace, which developed the flight control revisions for the Max, have completed revising the software package within the last two weeks. The pair was forced to tackle further changes to the software, including adjusting tolerances on sensors that were erroneously activating cockpit indications that the jet’s horizontal stabilizer was not properly configured. The companies are now in the last stages of “mopping up bits and pieces” of its protracted re-development that has stretched more than 20 months since the October 2018 crash of Lion Air 610 and Ethiopian Airlines 302 in March 2019, according to one industry official.
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Re: Boeing 737MAX Grounding, General Discussion Thread, May 2020

Fri Jun 12, 2020 6:35 am

Has there been any information released to date regarding how much re-certification has cost Boeing? Will they release this information at any point?

Just curious.
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Re: Boeing 737MAX Grounding, General Discussion Thread, May 2020

Fri Jun 12, 2020 7:07 am

The situation is in some sense good news, production starting (even with need for much less shipsets from Spirit). But when I read stuff like:

oschkosch wrote:
The companies are now in the last stages of “mopping up bits and pieces” of its protracted re-development that has stretched more than 20 months


... I get worried. In software "mopping up bits and pieces" stage usually means there's 90% of the work left :-)

It is done when it is done. When you have no pending bugs to fix, no unfilled requirements from the regulators, all reviews done, all certification complete. Before that, the results are rather unpredictable.
 
 
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Revelation
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Re: Boeing 737MAX Grounding, General Discussion Thread, May 2020

Fri Jun 12, 2020 10:39 am

AirbusOnly wrote:

So they already have 6 and may reject 10 which would leave them in an awkward position owning a pretty small sub fleet.

However, given COVID and its recovery, they probably are better off not taking any new aircraft.

And the cloud has a silver lining:

Morgunblaðið’s sources report that Icelandair officials deem it wiser to continue using their Boeing 757-200 aircraft instead - longer than initially planned. Operating them is economical while fuel costs remain as low as they have been in recent weeks.

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Re: Boeing 737MAX Grounding, General Discussion Thread, May 2020

Fri Jun 12, 2020 12:44 pm

Revelation wrote:
they probably are better off not taking any new aircraft


Indeed.

(It is actually amazing how in tune Boeing has been with its customers. While Airbus continues to peddle their product to the customers even at these hard times, Boeing pre-emptively disabled their ability to deliver certified airplanes. Imagine the celebration dances at the airline headquarters; not having to pay or take delivery of new aircraft when demand has tanked. Well done! :-) )
 
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Re: Boeing 737MAX Grounding, General Discussion Thread, May 2020

Fri Jun 12, 2020 5:12 pm

AirlineCritic wrote:
(It is actually amazing how in tune Boeing has been with its customers. While Airbus continues to peddle their product to the customers even at these hard times, Boeing pre-emptively disabled their ability to deliver certified airplanes. Imagine the celebration dances at the airline headquarters; not having to pay or take delivery of new aircraft when demand has tanked. Well done! :-) )

Yep, Airbus customers have a much more stressful life. They have to pretend to not hear the phone when Airbus calls, then be ready to hire lawyers once they are served papers from Airbus's lawyers.
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889091
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Re: Boeing 737MAX Grounding, General Discussion Thread, May 2020

Fri Jun 12, 2020 10:08 pm

Revelation wrote:
AirlineCritic wrote:
(It is actually amazing how in tune Boeing has been with its customers. While Airbus continues to peddle their product to the customers even at these hard times, Boeing pre-emptively disabled their ability to deliver certified airplanes. Imagine the celebration dances at the airline headquarters; not having to pay or take delivery of new aircraft when demand has tanked. Well done! :-) )

Yep, Airbus customers have a much more stressful life. They have to pretend to not hear the phone when Airbus calls, then be ready to hire lawyers once they are served papers from Airbus's lawyers.


Had the MAX debacle not happened, I am sure BCA would be doing the same thing. They are both in the business of building planes to make money. Having said that, these are unprecedented times and I do not believe either companies have encountered a similar situation like this since the inception of BCA or Airbus. Only time will tell how this will play out.
 
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Re: Boeing 737MAX Grounding, General Discussion Thread, May 2020

Fri Jun 12, 2020 10:46 pm

889091 wrote:
Revelation wrote:
AirlineCritic wrote:
(It is actually amazing how in tune Boeing has been with its customers. While Airbus continues to peddle their product to the customers even at these hard times, Boeing pre-emptively disabled their ability to deliver certified airplanes. Imagine the celebration dances at the airline headquarters; not having to pay or take delivery of new aircraft when demand has tanked. Well done! :-) )

Yep, Airbus customers have a much more stressful life. They have to pretend to not hear the phone when Airbus calls, then be ready to hire lawyers once they are served papers from Airbus's lawyers.


Had the MAX debacle not happened, I am sure BCA would be doing the same thing. They are both in the business of building planes to make money. Having said that, these are unprecedented times and I do not believe either companies have encountered a similar situation like this since the inception of BCA or Airbus. Only time will tell how this will play out.


Lets not forget that Boeing is currently being sued by at least two customers because they refuse to return deposits to customers for breach of contract cancellations due to the MAX saga... Its not all roses and hugs from Boeing.
 
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Sat Jun 13, 2020 2:22 pm

Seattle Times has reported In wake of 737 MAX crashes, Senate proposal would strengthen FAA oversight of Boeing plane designs

A proposed bill to tighten controls on how federal aviation safety regulators oversee and approve Boeing’s design of new jets has been hammered out by a Senate committee after backroom negotiations and a pressure campaign by families of the 346 people who died in two crashes of the 737 MAX.

If passed, the bill would reverse the years-long trend of delegating more and more control of the process to Boeing itself, and would shift the balance of oversight responsibility back toward the Federal Aviation Administration (FAA).

It says Sen. Maria Cantwell (D, WA) has had to reverse positions from being pro-liberalization to pro-regulation. It says she and the victim's families had a key role in toughening up the early proposals which were proposals for studies rather than any actual changes in laws.

The meat of the bill seems to be:

The draft bill would restructure the organization within Boeing of company engineers who work on behalf of the FAA and are tasked with testing and approving the design of a new airplane.

Those engineers today are appointed by Boeing. According to a copy of the bill obtained by The Seattle Times, it requires that they be appointed by and approved by the FAA.

Those engineers today are supervised by Boeing managers and discouraged from talking directly to their FAA technical counterparts. The bill requires that the FAA regularly audit their performance and that they communicate routinely with an FAA technical advisor, typically a government safety engineer or inspector.

In addition, no FAA employee can be offered any kind of financial incentive for performance “related to meeting schedules.” And neither FAA nor Boeing management can prohibit the technical staff on either side from communicating freely with each other.

It seems to be a revision to the old AR scheme, which is something members here wanted to see.

It also strikes down paths towards full self-certification, has explicit protections for whistleblowers, and gives FAA $10M per year to hire specialists on emerging technology.

Victim's families want to see an even tougher law:

They want an explicit provision that all critical airplane systems — such as the flight control system that brought down the two MAXs, the Maneuvering Characteristics Augmentation System (MCAS) — must be approved directly by the FAA, not Boeing.

And they want some kind of sunset clause when an airplane is approved with a so-called Type Certificate, so that derivative models designed much later — perhaps 20 years after the original — must go through an entirely new certification process.

I'm not sure why these would be overly burdensome. Safety first, no?

Note the bill hasn't even left the Senate Committee, and if it does, it will be subject to change in House/Senate Conference, then if passed it will need to be signed by POTUS before it could become law.

I'm surprised this hasn't gotten attention on the forum. This kind of stuff was being discussed here for month after month. I suppose CV19 has put a general damper on this forum and this particular topic has faded away for many, but still if passed it could have impact for pretty much every aviation project out there.
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mxaxai
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Sat Jun 13, 2020 3:32 pm

Revelation wrote:
They want an explicit provision that all critical airplane systems — such as the flight control system that brought down the two MAXs, the Maneuvering Characteristics Augmentation System (MCAS) — must be approved directly by the FAA, not Boeing.

This seems sensible, although the definition of 'critical' will be important here. I don't think Boeing considered MCAS a 'critical' system prior to the crashes.
Revelation wrote:
And they want some kind of sunset clause when an airplane is approved with a so-called Type Certificate, so that derivative models designed much later — perhaps 20 years after the original — must go through an entirely new certification process.

This is ridiculous. Such a rule would limit the lifetime of any aircraft type to 20 years and not one day further.
It would mean that even minor changes would be cost prohibitive for older aircraft. For example, cargo conversion kits would need to be certified within 20 years after the original, or else they would require a completely new TC. Replacing old electronics with newer equipment (monitors, computers, wires, ...) might require a new TC if done after 20 years. Adding satcom might require a new TC. Even adding wireless chargers requires an STC today.
 
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Sat Jun 13, 2020 3:58 pm

mxaxai wrote:
Revelation wrote:
And they want some kind of sunset clause when an airplane is approved with a so-called Type Certificate, so that derivative models designed much later — perhaps 20 years after the original — must go through an entirely new certification process.

This is ridiculous. Such a rule would limit the lifetime of any aircraft type to 20 years and not one day further.
It would mean that even minor changes would be cost prohibitive for older aircraft. For example, cargo conversion kits would need to be certified within 20 years after the original, or else they would require a completely new TC. Replacing old electronics with newer equipment (monitors, computers, wires, ...) might require a new TC if done after 20 years. Adding satcom might require a new TC. Even adding wireless chargers requires an STC today.

I'm sure if such a clause was ever passed (and to be clear, it's not even part of the current proposal) this would need a bunch of clarification. 20 years does seem to be too short. Some clear definition of what a derivative is would need to be made. There is something wrong with 50+ year old systems architectures being perpetuated. The current rules created the environment where the incentive was to try to find a way to say MCAS was not a new function and to integrate it into the current FCC architecture. That's what the rule changes are trying to address, not a STC for wireless.
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smartplane
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Sat Jun 13, 2020 7:33 pm

Revelation wrote:
mxaxai wrote:
Revelation wrote:

This is ridiculous. Such a rule would limit the lifetime of any aircraft type to 20 years and not one day further.
It would mean that even minor changes would be cost prohibitive for older aircraft. For example, cargo conversion kits would need to be certified within 20 years after the original, or else they would require a completely new TC. Replacing old electronics with newer equipment (monitors, computers, wires, ...) might require a new TC if done after 20 years. Adding satcom might require a new TC. Even adding wireless chargers requires an STC today.

I'm sure if such a clause was ever passed (and to be clear, it's not even part of the current proposal) this would need a bunch of clarification. 20 years does seem to be too short. Some clear definition of what a derivative is would need to be made. There is something wrong with 50+ year old systems architectures being perpetuated. The current rules created the environment where the incentive was to try to find a way to say MCAS was not a new function and to integrate it into the current FCC architecture. That's what the rule changes are trying to address, not a STC for wireless.

The intention is not to be as restrictive as mxaxai portrays - more along the lines suggested by Revelation.

The issue is not new. It was raised when the MAX and 777X models were announced, and obviously during the MAX investigations.

The current arrangement is seen as a trade barrier to new entrants, and has been discussed and lobbied extensively by Mitsi, Embraer and Bombardier, and their respective airworthiness authorities (and China and Russia too).

Airbus has been muted on the subject, with a foot in both camps, though are yet to push the age and model envelope as far as Boeing. Boeing were vehemently against such restrictions. Engine OEM's have previously asked, how does this affect us?
 
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Sun Jun 14, 2020 7:13 am

Thank you Revelation for posting information about the proposed bill. I for one would like to see something like that. There's clearly a big role for the manufacturers in the certification process, but I would like to see some oversight in critical systems, and the proposed bill seems to be a reasonable one.
 
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Sun Jun 14, 2020 2:16 pm

Revelation wrote:
Seattle Times has reported In wake of 737 MAX crashes, Senate proposal would strengthen FAA oversight of Boeing plane designs

A proposed bill to tighten controls on how federal aviation safety regulators oversee and approve Boeing’s design of new jets has been hammered out by a Senate committee after backroom negotiations and a pressure campaign by families of the 346 people who died in two crashes of the 737 MAX.

If passed, the bill would reverse the years-long trend of delegating more and more control of the process to Boeing itself, and would shift the balance of oversight responsibility back toward the Federal Aviation Administration (FAA).

It says Sen. Maria Cantwell (D, WA) has had to reverse positions from being pro-liberalization to pro-regulation. It says she and the victim's families had a key role in toughening up the early proposals which were proposals for studies rather than any actual changes in laws.

The meat of the bill seems to be:

The draft bill would restructure the organization within Boeing of company engineers who work on behalf of the FAA and are tasked with testing and approving the design of a new airplane.

Those engineers today are appointed by Boeing. According to a copy of the bill obtained by The Seattle Times, it requires that they be appointed by and approved by the FAA.

Those engineers today are supervised by Boeing managers and discouraged from talking directly to their FAA technical counterparts. The bill requires that the FAA regularly audit their performance and that they communicate routinely with an FAA technical advisor, typically a government safety engineer or inspector.

In addition, no FAA employee can be offered any kind of financial incentive for performance “related to meeting schedules.” And neither FAA nor Boeing management can prohibit the technical staff on either side from communicating freely with each other.

It seems to be a revision to the old AR scheme, which is something members here wanted to see.

It also strikes down paths towards full self-certification, has explicit protections for whistleblowers, and gives FAA $10M per year to hire specialists on emerging technology.

Victim's families want to see an even tougher law:

They want an explicit provision that all critical airplane systems — such as the flight control system that brought down the two MAXs, the Maneuvering Characteristics Augmentation System (MCAS) — must be approved directly by the FAA, not Boeing.

And they want some kind of sunset clause when an airplane is approved with a so-called Type Certificate, so that derivative models designed much later — perhaps 20 years after the original — must go through an entirely new certification process.

I'm not sure why these would be overly burdensome. Safety first, no?

Note the bill hasn't even left the Senate Committee, and if it does, it will be subject to change in House/Senate Conference, then if passed it will need to be signed by POTUS before it could become law.

I'm surprised this hasn't gotten attention on the forum. This kind of stuff was being discussed here for month after month. I suppose CV19 has put a general damper on this forum and this particular topic has faded away for many, but still if passed it could have impact for pretty much every aviation project out there.


I agree this is a reversion to the old FAA/manufacturer system. The Washington State delegation's reversion and support of this law is significant. But we await the senate's final bill and approval. I think it will easily pass in the House.
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Sun Jun 14, 2020 2:24 pm

AirlineCritic wrote:
Thank you Revelation for posting information about the proposed bill. I for one would like to see something like that. There's clearly a big role for the manufacturers in the certification process, but I would like to see some oversight in critical systems, and the proposed bill seems to be a reasonable one.

The key to passage is money, as long as no new funding is being requested it has a chance, the small additional increase for the FAA hire technical personnel may not be a stumbling block unless it is worded to eliminate the OEM staff, in which case they can be viewed as a government subsidy. If they have to be industry specific non-OEM being inspected, some smart alec may simply say why not use NASA since government is already funding them, that NASA uses industry resources can be hidden in the shuffle.
 
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Sun Jun 14, 2020 7:34 pm

Here’s the problem with shifting the certification authority to the FAA from Boeing. The FAA is a government organization, which by definition is heavily influenced by politics. Its director and top personnel are appointed by politicians, not by people with any aeronautical knowledge. The lower level employees are then hired by them. Nothing guarantees that they will know anything, but under these proposals they will have almost absolute authority over certification without any guarantee that they will know a winglet from an aileron.

The system that developed was based on the understanding that the entity that was most concerned that airliners were safe was Boeing itself, as they were acutely aware that it is very bad for business to kill your customers. The MAX debacle is a symptom of the rot that has taken place in Boeing culture, and the fact that they can no longer be trusted to act in their own best interest. So what is the solution? I am not sure. I would like to see the entire Board of Directors replaced, along with every executive above middle level. Boeing grew to where it was by putting engineers over accountants and making safety the first, second, third, and fourteenth priority. But ever since McDonnell Douglas bought Boeing with Boeing’s money it seems that the accountants have gained supremacy, and first we had the 787 cockup and now the MAX disaster as a direct result. More government oversight is a knee-jerk reaction, but will not fix the fundamental problem. Modern airliners are so complex that no outside engineer can adequately comprehend every possible scenario. Only the ones actually designing them can. And they have to have the directive that if they can envision even the remotest possibility of a failure, they must take it into account. That is the way Boeing, Douglas, Lockheed, and Convair engineers thought before McDonnell entered the picture with the military mindset that once you have met specifications you are done. That is the philosophy they applied to the DC-10, and it directly led to three crashes. And unfortunately it seems to have intruded itself far too much into Boeing, and it MUST be rooted out. That is the problem, not the lack of government oversight.

One of my life maxims is that government, by its very nature, is fundamentally incapable of competence. And it certainly applies here.
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Re: Boeing 737MAX Grounding, General Discussion Thread, May 2020

Mon Jun 15, 2020 7:35 am

oschkosch wrote:
Here's an interesting article! Mopping up bits and pieces: probably bits and bytes too! And some tests scheduled for May just didn't happen...

https://theaircurrent.com/aviation-safe ... ts-return/



Interesting, according to that article, there's a new condition for MCAS to activate - steep turn.
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Mon Jun 15, 2020 5:28 pm

SEPilot wrote:
One of my life maxims is that government, by its very nature, is fundamentally incapable of competence. And it certainly applies here.


That is perhaps a bit of a one sided view into this issue. Common among some folks out there, very common in US for instance.

But the problem is that many organisations have issues, from wrong incentives to lack of focus on right things such as politics over substance. Yet, many if not most organisations do quite well, others do more poorly. Even big corporations have failed spectacularly when they were went along the wrong path. And many government organisations do their job very, very well. I know many regulators and government / society employees who doing exactly what they should be doing and do it well, being experts and leaders in their field. Aviation administrations, accident investigators, health care professionals, etc. come to mind as excellent examples. In the nordic countries, for instance, the civil service system and agencies are generally quite capable. Yes, the top person may be a political appointee, but the organisations otherwise are run as focused on their task, and staffed with the right type of people.

Of course, there are exceptions. Generally, too much insulation from realities, income money flows and their tie-in to end-user satisfaction can lead to problems. That's not only a government problem, it happens in many private enterprises as well.

I'm always wary when people push a particular approach (e.g, commercial or government-run) as the only solution. Energy companies sold to private enterprises and then turned into local monopolies is one local example that I'm paying dearly for every month :-)

The reality is that a far better model would be that someone keeps tabs on what's going on, manages the organisation well, keeps them up to their promises. You can fail to do that for private enterprises just as well as government agencies.

(And in different parts of the world there are more specific issues, e.g., extreme pay differences between government and private world tends to lead to issues, for instance.)
 
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Re: Boeing 737MAX Grounding, General Discussion Thread, May 2020

Mon Jun 15, 2020 7:46 pm

sgrow787 wrote:
oschkosch wrote:
Here's an interesting article! Mopping up bits and pieces: probably bits and bytes too! And some tests scheduled for May just didn't happen...

https://theaircurrent.com/aviation-safe ... ts-return/



Interesting, according to that article, there's a new condition for MCAS to activate - steep turn.

It’s only referenced in the graphic, though. I wonder if they’re referring to the wind-up turn, but the info was not correctly conferred to whoever made up that graphic. However, I believe the MCAS trigger during a wind-up turn is still AOA. The high AOA is just a product of the maneuver.
 
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Re: Boeing 737MAX Grounding, General Discussion Thread, May 2020

Mon Jun 15, 2020 8:05 pm

sgrow787 wrote:
oschkosch wrote:
Here's an interesting article! Mopping up bits and pieces: probably bits and bytes too! And some tests scheduled for May just didn't happen...

https://theaircurrent.com/aviation-safe ... ts-return/



Interesting, according to that article, there's a new condition for MCAS to activate - steep turn.

It was that way from the beginning - "wind up turn" is the most likely condition for MCAS activation. This is actually one of major scenarios when high lift / AoA is required as generated lift is needed for both centripetal acceleration and vertical force to counteract gravity.
 
Dogman
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Mon Jun 15, 2020 8:23 pm

SEPilot wrote:
One of my life maxims is that government, by its very nature, is fundamentally incapable of competence. And it certainly applies here.


How sad for you. Although in this case you are right. But then again, you get what you pay for.
 
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Re: Boeing 737MAX Grounding, General Discussion Thread, May 2020

Mon Jun 15, 2020 9:10 pm

oschkosch wrote:
Here's an interesting article! Mopping up bits and pieces: probably bits and bytes too! And some tests scheduled for May just didn't happen...

I think the most interesting content is a possible scenario to appease EASA:

EASA’s requirements for the aircraft will spawn additional development work on the 737 Max after it returns to service. Specifically, one of the people familiar with the changes said Boeing, FAA and EASA agreed to implement a synthetic airspeed or equivalent system on the Max as a further source of data into the flight control computers.

Yet it won't happen very quickly:

One of the officials familiar with the planning said it could take “a couple years” to field the new synthetic airspeed changes but the regulators want action “sooner if possible.” One of the industry officials suggested that the final compliance with EASA’s requirements could include the addition of a third mechanical AoA sensor for the aircraft, a much more invasive hardware change that would need to be fielded across the full fleet of Max aircraft, now 800 and growing.

That seems quite dubious to me. Either the plane is safe and doesn't need a 3rd air data source, or it's unsafe and needs a 3rd air data source before it flies again. This is the kind of nonsense you get once politicians get involved.

As an aside, the author isn't too happy with how the content he produced is being used:

I just came across a YouTube channel with 200,000+ subscribers that has decided to publish a 737 Max update that includes reading to camera, nearly verbatim, @theaircurrent reporting. Would you believe he didn’t cite his sources?

Ref: https://twitter.com/jonostrower/status/ ... 8720972807

And no, he's not referring to the young guy from Australia...
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aerolimani
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Mon Jun 15, 2020 10:21 pm

Whether it wants a 3rd AOA probe, or doesn’t, is not a question of safe or unsafe. Safe or unsafe is not an on/off switch. The question is whether the regulators feel that the plane is sufficiently safe with only two AOA probes, or not. That is a question of opinion.

Generally, if you ask people whether they prefer more or less safe, they will choose more. Of course, there will come a point, sometimes shockingly rapidly, where their willingness to forego safety over cost will cause them to forego the extra safety. Generally, with corporations, they prefer to meet the regulations and no more. Thus, it falls to the politicians/regulators to make this choice for us.
 
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par13del
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Mon Jun 15, 2020 11:03 pm

aerolimani wrote:
Whether it wants a 3rd AOA probe, or doesn’t, is not a question of safe or unsafe. Safe or unsafe is not an on/off switch. The question is whether the regulators feel that the plane is sufficiently safe with only two AOA probes, or not. That is a question of opinion.

I would expect the experts to say that since the MAX is attempting to have more automation directly related to air speed it should follow the A320 example and use 3 sensors, so not an opinion, but if we want to call it an opinion, it is based on 30+ years of their 737 competitor.
In my opinion, Boeing should implement the 3 sensors versus their software alternative approach, right now there may be 800 a/c to modify, they may even be given time to do so, versus the potential of 3,000+ a/c yet to be built. The computers on the MAX have already been found wanting for the additional processing needs, why increase that for what is still a non-FBW a/c, take the hit on additional cost which would mostly be hardware - sensor and wires - versus all software.
 
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Stitch
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Mon Jun 15, 2020 11:12 pm

par13del wrote:
In my opinion, Boeing should implement the 3 sensors versus their software alternative approach, right now there may be 800 a/c to modify, they may even be given time to do so, versus the potential of 3,000+ a/c yet to be built. The computers on the MAX have already been found wanting for the additional processing needs, why increase that for what is still a non-FBW a/c, take the hit on additional cost which would mostly be hardware - sensor and wires - versus all software.


The impression I get from the article is that EASA at a minimum is pushing for the "software alternative" (the synthetic airspeed system), but is also considering also requiring a third AoA sensor so that you can have a "quorum".
 
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SEPilot
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Mon Jun 15, 2020 11:24 pm

AirlineCritic wrote:
SEPilot wrote:
One of my life maxims is that government, by its very nature, is fundamentally incapable of competence. And it certainly applies here.


That is perhaps a bit of a one sided view into this issue. Common among some folks out there, very common in US for instance.

But the problem is that many organisations have issues, from wrong incentives to lack of focus on right things such as politics over substance. Yet, many if not most organisations do quite well, others do more poorly. Even big corporations have failed spectacularly when they were went along the wrong path. And many government organisations do their job very, very well. I know many regulators and government / society employees who doing exactly what they should be doing and do it well, being experts and leaders in their field. Aviation administrations, accident investigators, health care professionals, etc. come to mind as excellent examples. In the nordic countries, for instance, the civil service system and agencies are generally quite capable. Yes, the top person may be a political appointee, but the organisations otherwise are run as focused on their task, and staffed with the right type of people.

Of course, there are exceptions. Generally, too much insulation from realities, income money flows and their tie-in to end-user satisfaction can lead to problems. That's not only a government problem, it happens in many private enterprises as well.

I'm always wary when people push a particular approach (e.g, commercial or government-run) as the only solution. Energy companies sold to private enterprises and then turned into local monopolies is one local example that I'm paying dearly for every month :-)

The reality is that a far better model would be that someone keeps tabs on what's going on, manages the organisation well, keeps them up to their promises. You can fail to do that for private enterprises just as well as government agencies.

(And in different parts of the world there are more specific issues, e.g., extreme pay differences between government and private world tends to lead to issues, for instance.)

OK, I admit my maxim is an exaggeration. And you are quite right that some in government service do their jobs very well. But there is a mindset that I believe is very dangerous, and that is tat if the government takes something over the problem is solved and it will be done properly. In my experience and observation that is seldom the case. In this case the problem is that the FAA, if it is to properly oversee the certification of Boeing’s airliners, really needs a crew of engineers knowledgeable of and experienced in airliner design. The catch is the entire supply of such individuals in this country is already working for Boeing.
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par13del
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Mon Jun 15, 2020 11:36 pm

Stitch wrote:
par13del wrote:
In my opinion, Boeing should implement the 3 sensors versus their software alternative approach, right now there may be 800 a/c to modify, they may even be given time to do so, versus the potential of 3,000+ a/c yet to be built. The computers on the MAX have already been found wanting for the additional processing needs, why increase that for what is still a non-FBW a/c, take the hit on additional cost which would mostly be hardware - sensor and wires - versus all software.


The impression I get from the article is that EASA at a minimum is pushing for the "software alternative" (the synthetic airspeed system), but is also considering also requiring a third AoA sensor so that you can have a "quorum".

My read is they will accept the synthetic which will take time for Boeing to implement, but once they agree, EASA will sign off on RTS.
My thought is that Boeing proposed synthetic versus going hardware, hopefully they know exactly how much processing power and additional modifications are required for the existing computers, as we can be sure they are not going to change those. I just think based on the MCAS and simultaneous computer adjustment, it will be more complicated to add additional software capability including the final cost, additionally, it will be something that EASA will be holding over their head for the next year or two that it takes to implement and the number of a/c requiring retrofit will be much larger. I guess I just think the pitfalls for the software alternative are greater.
 
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par13del
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Mon Jun 15, 2020 11:40 pm

SEPilot wrote:
The catch is the entire supply of such individuals in this country is already working for Boeing.

Ahh, but now you run into the strength of government, since they play with monopoly money, they can easily implement a retirement age for those engineers of 50 years at Boeing then 10 years at the FAA with a raise. When you play with fake money you can get very creative.
 
2175301
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Tue Jun 16, 2020 3:27 am

par13del wrote:
SEPilot wrote:
The catch is the entire supply of such individuals in this country is already working for Boeing.

Ahh, but now you run into the strength of government, since they play with monopoly money, they can easily implement a retirement age for those engineers of 50 years at Boeing then 10 years at the FAA with a raise. When you play with fake money you can get very creative.



I have never seen the government pay more money for techically qualified people than the private sector. The US Nuclear Regulatory Commission (NRC) pays about 75-80% of what the nuclear plants pay, and the NRC requires the plants to pay for every man-hour they spend inspecting, investigating, and resolving (to their satisfaction) any identified issues.
 
FluidFlow
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Tue Jun 16, 2020 7:59 am

2175301 wrote:
par13del wrote:
SEPilot wrote:
The catch is the entire supply of such individuals in this country is already working for Boeing.

Ahh, but now you run into the strength of government, since they play with monopoly money, they can easily implement a retirement age for those engineers of 50 years at Boeing then 10 years at the FAA with a raise. When you play with fake money you can get very creative.



I have never seen the government pay more money for techically qualified people than the private sector. The US Nuclear Regulatory Commission (NRC) pays about 75-80% of what the nuclear plants pay, and the NRC requires the plants to pay for every man-hour they spend inspecting, investigating, and resolving (to their satisfaction) any identified issues.


I don't know how it is in the US with government jobs, but here in Switzerland, even though the pay is also not as good, you have one of the best retirement schemes, really good social benefits and a really safe job. So I know many people that went in their 40s and early 50s to the government to work until retirement as the pay is still good and the other benefits make up for the lost wages + government jobs are in general less stressful as the government has its own deadlines. If it takes longer then that's it, the certification can also be done later that year.

So while the government normally does a good job it just takes way longer as it is just a 9-5 job. No stress, ok pay, good benefits.
 
sgrow787
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Tue Jun 16, 2020 8:41 am

par13del wrote:
aerolimani wrote:
Whether it wants a 3rd AOA probe, or doesn’t, is not a question of safe or unsafe. Safe or unsafe is not an on/off switch. The question is whether the regulators feel that the plane is sufficiently safe with only two AOA probes, or not. That is a question of opinion.

I would expect the experts to say that since the MAX is attempting to have more automation directly related to air speed it should follow the A320 example and use 3 sensors, so not an opinion, but if we want to call it an opinion, it is based on 30+ years of their 737 competitor.
In my opinion, Boeing should implement the 3 sensors versus their software alternative approach, right now there may be 800 a/c to modify, they may even be given time to do so, versus the potential of 3,000+ a/c yet to be built. The computers on the MAX have already been found wanting for the additional processing needs, why increase that for what is still a non-FBW a/c, take the hit on additional cost which would mostly be hardware - sensor and wires - versus all software.


More sensors with the current FCC hardware is the problem. It's likely not feasible, hence the synthetic airspeed.
Just one sensor,
Oh just one se-en-sor,
Just one sensor,
Ooh ooh oo-ooh
Oo-oo-ooh.
 
sgrow787
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Tue Jun 16, 2020 8:51 am

SEPilot wrote:
AirlineCritic wrote:
SEPilot wrote:
One of my life maxims is that government, by its very nature, is fundamentally incapable of competence. And it certainly applies here.


That is perhaps a bit of a one sided view into this issue. Common among some folks out there, very common in US for instance.

But the problem is that many organisations have issues, from wrong incentives to lack of focus on right things such as politics over substance. Yet, many if not most organisations do quite well, others do more poorly. Even big corporations have failed spectacularly when they were went along the wrong path. And many government organisations do their job very, very well. I know many regulators and government / society employees who doing exactly what they should be doing and do it well, being experts and leaders in their field. Aviation administrations, accident investigators, health care professionals, etc. come to mind as excellent examples. In the nordic countries, for instance, the civil service system and agencies are generally quite capable. Yes, the top person may be a political appointee, but the organisations otherwise are run as focused on their task, and staffed with the right type of people.

Of course, there are exceptions. Generally, too much insulation from realities, income money flows and their tie-in to end-user satisfaction can lead to problems. That's not only a government problem, it happens in many private enterprises as well.

I'm always wary when people push a particular approach (e.g, commercial or government-run) as the only solution. Energy companies sold to private enterprises and then turned into local monopolies is one local example that I'm paying dearly for every month :-)

The reality is that a far better model would be that someone keeps tabs on what's going on, manages the organisation well, keeps them up to their promises. You can fail to do that for private enterprises just as well as government agencies.

(And in different parts of the world there are more specific issues, e.g., extreme pay differences between government and private world tends to lead to issues, for instance.)

OK, I admit my maxim is an exaggeration. And you are quite right that some in government service do their jobs very well. But there is a mindset that I believe is very dangerous, and that is tat if the government takes something over the problem is solved and it will be done properly. In my experience and observation that is seldom the case. In this case the problem is that the FAA, if it is to properly oversee the certification of Boeing’s airliners, really needs a crew of engineers knowledgeable of and experienced in airliner design. The catch is the entire supply of such individuals in this country is already working for Boeing.


Actually, there's a lot of engineers in the US displaced by outsourcing that have experience and a solid base of knowledge. It probably would help to have the head of the FAA be a retired aerospace engineer rather than a pilot.
Just one sensor,
Oh just one se-en-sor,
Just one sensor,
Ooh ooh oo-ooh
Oo-oo-ooh.
 
sgrow787
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Tue Jun 16, 2020 8:57 am

aerolimani wrote:
Whether it wants a 3rd AOA probe, or doesn’t, is not a question of safe or unsafe. Safe or unsafe is not an on/off switch. The question is whether the regulators feel that the plane is sufficiently safe with only two AOA probes, or not. That is a question of opinion.

Generally, if you ask people whether they prefer more or less safe, they will choose more. Of course, there will come a point, sometimes shockingly rapidly, where their willingness to forego safety over cost will cause them to forego the extra safety. Generally, with corporations, they prefer to meet the regulations and no more. Thus, it falls to the politicians/regulators to make this choice for us.


The probability of failure goes down exponentially when you add a sensor to the redundancy. So you don't usually get to barely meet the regulations in that regard. Companies use all the sensors that are available to them rather than mitigate failures with a complex FMEA analysis (unless adding sensors to antiquated hardware isn't feasible). Add just one more sensor to the Max and I'll take your worst pilots, worst maintenance crew, worst repair shop, and the plane still lands every time.
Just one sensor,
Oh just one se-en-sor,
Just one sensor,
Ooh ooh oo-ooh
Oo-oo-ooh.
 
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ADent
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Tue Jun 16, 2020 9:54 am

I thought EASA always wanted a third sensor, but was willing to accept a synthetic sensor.

Without a 3rd senior how do you handle a AOA mis-compare?

One answer was to turn off MCAS with a miscompare. Boeing says that is generally safe.

Which leads the Canadians to ask can we test fly it w/o MCAS, and if it so safe can we just eliminate the killer MCAS completely?
 
planecane
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Tue Jun 16, 2020 11:19 am

sgrow787 wrote:
aerolimani wrote:
Whether it wants a 3rd AOA probe, or doesn’t, is not a question of safe or unsafe. Safe or unsafe is not an on/off switch. The question is whether the regulators feel that the plane is sufficiently safe with only two AOA probes, or not. That is a question of opinion.

Generally, if you ask people whether they prefer more or less safe, they will choose more. Of course, there will come a point, sometimes shockingly rapidly, where their willingness to forego safety over cost will cause them to forego the extra safety. Generally, with corporations, they prefer to meet the regulations and no more. Thus, it falls to the politicians/regulators to make this choice for us.


The probability of failure goes down exponentially when you add a sensor to the redundancy. So you don't usually get to barely meet the regulations in that regard. Companies use all the sensors that are available to them rather than mitigate failures with a complex FMEA analysis (unless adding sensors to antiquated hardware isn't feasible). Add just one more sensor to the Max and I'll take your worst pilots, worst maintenance crew, worst repair shop, and the plane still lands every time.


Actually, the probability of a failure goes UP with an added sensor. If the logic is well designed, the probability of a catastrophic RESULT of a failure goes down.
 
planecane
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Tue Jun 16, 2020 11:23 am

ADent wrote:
I thought EASA always wanted a third sensor, but was willing to accept a synthetic sensor.

Without a 3rd senior how do you handle a AOA mis-compare?

One answer was to turn off MCAS with a miscompare. Boeing says that is generally safe.

Which leads the Canadians to ask can we test fly it w/o MCAS, and if it so safe can we just eliminate the killer MCAS completely?

How do you handle an engine failure? There is a procedure to follow.

How do you handle an AoA mismatch? There will be a procedure to follow.

The real issue with only 2 sensors is both failing in the same direction within 5° of each other. Then the FCC won't know there is a failure. I imagine the probability of that is incredibly low and within regulations.
 
planecane
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Tue Jun 16, 2020 11:26 am

sgrow787 wrote:
par13del wrote:
aerolimani wrote:
Whether it wants a 3rd AOA probe, or doesn’t, is not a question of safe or unsafe. Safe or unsafe is not an on/off switch. The question is whether the regulators feel that the plane is sufficiently safe with only two AOA probes, or not. That is a question of opinion.

I would expect the experts to say that since the MAX is attempting to have more automation directly related to air speed it should follow the A320 example and use 3 sensors, so not an opinion, but if we want to call it an opinion, it is based on 30+ years of their 737 competitor.
In my opinion, Boeing should implement the 3 sensors versus their software alternative approach, right now there may be 800 a/c to modify, they may even be given time to do so, versus the potential of 3,000+ a/c yet to be built. The computers on the MAX have already been found wanting for the additional processing needs, why increase that for what is still a non-FBW a/c, take the hit on additional cost which would mostly be hardware - sensor and wires - versus all software.


More sensors with the current FCC hardware is the problem. It's likely not feasible, hence the synthetic airspeed.


Agreed. I can't imagine there is a spare input on the FCC to accept a 3rd AoA sensor. It would require replacing the FCC or adding some kind of AoA processor that takes 3 sensor inputs and outputs 2 signals compatible with the FCC.
 
kalvado
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Tue Jun 16, 2020 11:51 am

planecane wrote:
How do you handle an engine failure? There is a procedure to follow.

How do you handle an AoA mismatch? There will be a procedure to follow.

The real issue with only 2 sensors is both failing in the same direction within 5° of each other. Then the FCC won't know there is a failure. I imagine the probability of that is incredibly low and within regulations.

Question is about the procedure to be used. It may turn out that MCAS out procedure ends up more invasive than engine-out procedure, and estimated risk is still higher.
 
morrisond
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Tue Jun 16, 2020 12:08 pm

sgrow787 wrote:
aerolimani wrote:
Whether it wants a 3rd AOA probe, or doesn’t, is not a question of safe or unsafe. Safe or unsafe is not an on/off switch. The question is whether the regulators feel that the plane is sufficiently safe with only two AOA probes, or not. That is a question of opinion.

Generally, if you ask people whether they prefer more or less safe, they will choose more. Of course, there will come a point, sometimes shockingly rapidly, where their willingness to forego safety over cost will cause them to forego the extra safety. Generally, with corporations, they prefer to meet the regulations and no more. Thus, it falls to the politicians/regulators to make this choice for us.


The probability of failure goes down exponentially when you add a sensor to the redundancy. So you don't usually get to barely meet the regulations in that regard. Companies use all the sensors that are available to them rather than mitigate failures with a complex FMEA analysis (unless adding sensors to antiquated hardware isn't feasible). Add just one more sensor to the Max and I'll take your worst pilots, worst maintenance crew, worst repair shop, and the plane still lands every time.


Yes of course - no airplane with 3 sensors has ever crashed due to control or handling issues.....

It is not a panacea.
 
kalvado
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Tue Jun 16, 2020 12:17 pm

morrisond wrote:
sgrow787 wrote:
aerolimani wrote:
Whether it wants a 3rd AOA probe, or doesn’t, is not a question of safe or unsafe. Safe or unsafe is not an on/off switch. The question is whether the regulators feel that the plane is sufficiently safe with only two AOA probes, or not. That is a question of opinion.

Generally, if you ask people whether they prefer more or less safe, they will choose more. Of course, there will come a point, sometimes shockingly rapidly, where their willingness to forego safety over cost will cause them to forego the extra safety. Generally, with corporations, they prefer to meet the regulations and no more. Thus, it falls to the politicians/regulators to make this choice for us.


The probability of failure goes down exponentially when you add a sensor to the redundancy. So you don't usually get to barely meet the regulations in that regard. Companies use all the sensors that are available to them rather than mitigate failures with a complex FMEA analysis (unless adding sensors to antiquated hardware isn't feasible). Add just one more sensor to the Max and I'll take your worst pilots, worst maintenance crew, worst repair shop, and the plane still lands every time.


Yes of course - no airplane with 3 sensors has ever crashed due to control or handling issues.....

It is not a panacea.

Yet education helps. Make schools great gain! It would help Boeing to get somewhat decent engineers. It would help the general public to get an idea of probability and risk analysis. As a fringe benefit, it may help to reduce inequality in society and maybe reduce number of pilot's errors. Win-win-win!
 
brindabella
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Tue Jun 16, 2020 12:59 pm

ADent wrote:
I thought EASA always wanted a third sensor, but was willing to accept a synthetic sensor.

Without a 3rd senior how do you handle a AOA mis-compare?

One answer was to turn off MCAS with a miscompare. Boeing says that is generally safe.

Which leads the Canadians to ask can we test fly it w/o MCAS, and if it so safe can we just eliminate the killer MCAS completely?



Hmmm.

:scratchchin:

5,000 command A320, technical software background.

I was always leary about the "2 versus1" voting system which is clearly what EASA has always wanted for the non-digital, non-FBW MAX.

And on cue I have noted references to situations where a healthy FMC (for instance) has been voted into silence by the other "healthy" one and aided by ... :shock: :shock: :shock:

cheers
Billy
 
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Revelation
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Tue Jun 16, 2020 1:52 pm

aerolimani wrote:
Whether it wants a 3rd AOA probe, or doesn’t, is not a question of safe or unsafe. Safe or unsafe is not an on/off switch. The question is whether the regulators feel that the plane is sufficiently safe with only two AOA probes, or not. That is a question of opinion.

Generally, if you ask people whether they prefer more or less safe, they will choose more. Of course, there will come a point, sometimes shockingly rapidly, where their willingness to forego safety over cost will cause them to forego the extra safety. Generally, with corporations, they prefer to meet the regulations and no more. Thus, it falls to the politicians/regulators to make this choice for us.

Where you say opinion, I'd say judgment. The role of the regulators is to judge whether a solution meets the requirements or not. By hedging this way they are shirking their responsibility, and saying it's good enough to fly without but needs a 3rd AOA source soon-ish is IMO shirking their responsibility.

The ugly scenario would be if we have an accident with fatalities involving loss of control before the 3rd source is in place, the finger pointing would be unreal.

par13del wrote:
My read is they will accept the synthetic which will take time for Boeing to implement, but once they agree, EASA will sign off on RTS.

To be clear, the article says resolution of the 3rd data source issue will happen after RTS, which is IMO troubling.
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Wake now, discover that you are the song that the morning brings
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kalvado
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Tue Jun 16, 2020 2:59 pm

Revelation wrote:
aerolimani wrote:
Whether it wants a 3rd AOA probe, or doesn’t, is not a question of safe or unsafe. Safe or unsafe is not an on/off switch. The question is whether the regulators feel that the plane is sufficiently safe with only two AOA probes, or not. That is a question of opinion.

Generally, if you ask people whether they prefer more or less safe, they will choose more. Of course, there will come a point, sometimes shockingly rapidly, where their willingness to forego safety over cost will cause them to forego the extra safety. Generally, with corporations, they prefer to meet the regulations and no more. Thus, it falls to the politicians/regulators to make this choice for us.

Where you say opinion, I'd say judgment. The role of the regulators is to judge whether a solution meets the requirements or not. By hedging this way they are shirking their responsibility, and saying it's good enough to fly without but needs a 3rd AOA source soon-ish is IMO shirking their responsibility.

The ugly scenario would be if we have an accident with fatalities involving loss of control before the 3rd source is in place, the finger pointing would be unreal.

par13del wrote:
My read is they will accept the synthetic which will take time for Boeing to implement, but once they agree, EASA will sign off on RTS.

To be clear, the article says resolution of the 3rd data source issue will happen after RTS, which is IMO troubling.

Everything is about risk analysis. If you don't want any risk at all, don't fly: there is always a chance that both - or even all four - engines would fail, or there was an undetected defect in one of the structural castings, or... Also don't go outside (meteorite, cancer from UV, vehicle hits), don't stay indoors (fire or CO poisoning, risk of COVID spreading) and so on.
How much longer planes were allowed to fly without tank inerting after TWA880?
Similar situation - shutdown of major companies (airlines, Boeing), lack of means to move around - vs some increased risk. I am sure there are some numbers at EASA and Boeing showing the scale of the problem, and it is probably lower than the current crash rate of NG fleet. Lets try to improve - but there is no need to panic.
 
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Stitch
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Tue Jun 16, 2020 3:06 pm

Revelation wrote:
To be clear, the article says resolution of the 3rd data source issue will happen after RTS, which is IMO troubling.


But at least this time around the pilots will:

a) Know MCAS exists;
b) Have been trained on how it works and understand how it can affect the handling of their airframe;
c) Have been trained on procedures on how to engage with it and, if necessary, turn it off;
 
889091
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Tue Jun 16, 2020 3:25 pm

Stitch wrote:
Revelation wrote:
To be clear, the article says resolution of the 3rd data source issue will happen after RTS, which is IMO troubling.


But at least this time around the pilots will:

a) Know MCAS exists;
b) Have been trained on how it works and understand how it can affect the handling of their airframe;
c) Have been trained on procedures on how to engage with it and, if necessary, turn it off;


Prior to the 2 fatal crashes that caused the grounding of the entire fleet, do we have any statistical data that shows how many times MCAS was actually activated across the whole fleet of MAXs that were flying globally?

I am just trying to get an idea of how long we have to wait post RTS, where MCAS is triggered in real-life, to validate that the fixes really work.
 
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Revelation
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Re: Boeing 737MAX Grounding, General Discussion Thread, Q2 2020

Tue Jun 16, 2020 3:31 pm

kalvado wrote:
Revelation wrote:
To be clear, the article says resolution of the 3rd data source issue will happen after RTS, which is IMO troubling.

Everything is about risk analysis. If you don't want any risk at all, don't fly: there is always a chance that both - or even all four - engines would fail, or there was an undetected defect in one of the structural castings, or... Also don't go outside (meteorite, cancer from UV, vehicle hits), don't stay indoors (fire or CO poisoning, risk of COVID spreading) and so on.
How much longer planes were allowed to fly without tank inerting after TWA880?
Similar situation - shutdown of major companies (airlines, Boeing), lack of means to move around - vs some increased risk. I am sure there are some numbers at EASA and Boeing showing the scale of the problem, and it is probably lower than the current crash rate of NG fleet. Lets try to improve - but there is no need to panic.

Let's not personalize this. If this is about me, I'd have flown in a MAX after the first fixes around a year ago, before the bit flip changes, and with a bunch of iPad training to explain MCAS and its updated fix.

I'm just saying it's troubling that the regulators seem to be hedging their bets by saying a change is needed (when it probably is not) yet we'll fly without it (opening up Pandora's box and leading to a 2nd grounding if there is an accident/incident before it is implemented).

Stitch wrote:
Revelation wrote:
To be clear, the article says resolution of the 3rd data source issue will happen after RTS, which is IMO troubling.

But at least this time around the pilots will:

a) Know MCAS exists;
b) Have been trained on how it works and understand how it can affect the handling of their airframe;
c) Have been trained on procedures on how to engage with it and, if necessary, turn it off;

Also suggests to me the 3rd AOA input probably isn't needed.

One thing we did learn from MCAS 1.0 was that adding more features to old tech can lead to unintended consequences, poorly understood failure modes, etc. It might be better to focus on making sure the pilots understand what the current tech can/cannot do rather than to try to get to full envelope protection one bug fix at a time.
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