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JibberJim
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sat Jul 27, 2019 9:34 pm

XRAYretired wrote:
In the middle of the conversation, an F.A.A. employee, one of the people said, interrupted to ask a question on the minds of several agency engineers: Why hadn’t Boeing updated the safety analysis of a system that had become so dangerous?'


That's an interesting one for the FAA though, did they insist on an immediate proper safety analysis, and if not why not? and if they did, why and how was the conclusion incompatible with the reality given the second crash and the grounding, or if it was appropriate, why were the planes not grounded?
 
Draken21fx
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sat Jul 27, 2019 9:49 pm

MartijnNL wrote:
factsonly wrote:
A B737MAX is flying today!

Today Saturday 27 July, TUI Netherlands is ferrying a stranded B737MAX from Sofia back to base in Amsterdam.

Thank you for the heads up. I saw it gliding through the sky this afternoon. Apparently the entire flight was done at 20,000 feet and 300 knots.


Did they fly with flaps extended by any chance in order for the MCAS not to kick in?
 
Lootess
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sat Jul 27, 2019 9:53 pm

MartijnNL wrote:
snowkarl wrote:
It cannot be cancelled.

Of course it can be cancelled. Just do it. And start building something else.

snowkar wrote:
Not only is there no replacement within at least 5 years (A and B backlogs for same efficiency or similar planes) but Boeing would lose an incredibly large part of the market as well as all brand trust and probably disappear fairly quickly.

Boeing would actually regain trust by ditching this failed aircraft type. Even without a replacement in the next five years the world will continue to revolve just fine. Less aircraft in the sky doesn't equal more problems.

snowkar wrote:
They really have no choice but to fix it, whatever it takes, because they bet it literally everything on this makeshift product.

They should concentrate on something else, the 797 maybe. Or on the development of a higher landing gear that removes the need for the engine to be placed where it is now.

snowkar wrote:
Because they stopped investing in future products, research and development, they are now playing constant catch up to Airbus, which has led to this current issue. It will take them decades to get back to where they used to, and should be at.

If NASA can put men on the Moon in eight years, why should it take decades for Boeing to get back to where they used to be?

I like to fly on the 737, 747, 757, 767 and 777. I stay away from the 787 (because of the crew override option on the dimmable windows) and the 737 Max, also after it will be deemed safe to travel on.

I feel sad that this all happened. Visiting the Boeing factory in Everett in 2017 was one of the greatest moments of my life.


The MAX is going to live on, there is just too much at-stake for the Boeing Renton factory since the NG is out the door, and the amount of orders that haven't cancelled is telling about the trust their customers are placing in the program. But how long the MAX program lasts is another story.
 
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flyingphil
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sat Jul 27, 2019 10:08 pm

Just when I thought there may be light at the end of the tunnel.. an issue with the rudder cables.
https://www.seattletimes.com/nation-wor ... oversight/

“Early on, engineers at the FAA discovered a problem with one of the most important new features of the MAX: its engines. The MAX, the latest version of the 50-year-old 737, featured more fuel-efficient engines, with a larger fan and a high-pressure turbine. But the bigger, more complex engines could do more damage if they broke apart midair.

The FAA engineers were particularly concerned about pieces hitting the cables that control the rudder, according to five people with knowledge of the matter and internal agency documents. A cable severed during takeoff would make it difficult for pilots to regain control, potentially bringing down the jet.... “
 
maverick4002
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sat Jul 27, 2019 10:29 pm

TaromA380 wrote:
I remember that back in March after the ET crash, the FAA was repeating its conviction that the MAX is safe and it won’t ground it, even after the finding that MCAS was again involved and despite being grounded by all the other relevant NAAs. Then, out of nowhere, Trump stepped in and decreed the grounding over the FAA itself.
He could as well tweet that the Max is okay back then. To outsider me, the U.S. president doesn’t look like a weak link in the responsibilities chain in this particular aviation affair. Quite the contrary.


You cannot be serious with this comment
 
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par13del
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sat Jul 27, 2019 10:36 pm

seahawk wrote:
The question is, do those smaller carrier need something with 797 capabilities or something with 737 capabilities. I would think the later.

When you consider a number of them are national carriers with limited resources a one size fits all 797 may be better than a 737.
Example UP, have routes to the USA with MIA as the main gateway, two or three hours to NYC or ORD on a 797 is more comfortable for tourist than a 737, at present, they do not have the resources to have 737 plus wide body. Most of the Caribbean carriers would probably love something in that size, even like the A321 which allows them to serve near east coast and mid-America, I think the Europeans have effectively driven them from Europe so USA and South and Central America is now the primary markets. The 737 is fine throughout the Caribbean, but most carriers cannot survive on that market, they also need to serve the primary tourist market which is the USA, the main gateways are covered by US carriers, they need something to open secondary routes where the 737 may struggle. Range is not always the issue, capacity is also.
 
art
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sat Jul 27, 2019 11:18 pm

Am I mistaken or does the certification of the MAX seem less and less justifiable as more and more defects/shortcomings in the process are revealed?

- MCAS and modification made post FAA assessment (increase in pitch down angle when activated)
- reported identification of processor overload scenario. How come it was not spotted and rectified before certification?
- reported FAA engineer concerns over the risk of uncontained engine failure severing control cables. What action was taken?

What is the likelihood that these would be the only areas of concern to appear if the aircraft were taken through a thorough certification process from scratch? I would guess that it is very likely that several more failings that slipped through the MAX certification process would be discovered, demonstrating it should never have been certified in the first place.
 
frmrCapCadet
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sat Jul 27, 2019 11:47 pm

Art - reality is bad enough without imagining boogie men under the bed
Buffet: the airline business...has eaten up capital...like..no other (business)
 
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par13del
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 1:08 am

art wrote:
- reported identification of processor overload scenario. How come it was not spotted and rectified before certification?

Based on my read of the initial article on the FAA test, the pilots intentionally created a failure mode by crippling the "computer" to create the overload condition.
Not like MCAS, but they obviously had a failure mode they wanted to test, how that came about I don't recall seeing mentioned.
Maybe some whistle blower said something and they decided to put it to the test.
 
Canuck600
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 3:30 am

Would it be correct to assume that the carriers most likely to cancel would be the ones with smaller orders because A) the ones with the smaller orders likely don't have their long term fleet plans wrapped around going with the Max. B) Finding a replacement for a 5 frame order is easier then a 30 frame order? If you looking at a 5 plane order it's easier to life extend what you have & order/lease what you can't life extend?
 
JHwk
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 3:31 am

After the NYT article I am starting to feel like Boeing will have to do a hell of a lot of work to get the Max back in the air. I can picture the program either being cancelled or forced to go full FBW. The screwed up systematically, at many levels, and there is simply no way they can just “fix MCAS” at this point to get back in the air. It is amazing the have gotten this stupid.
 
2175301
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 3:45 am

Folks: If you will recall, for those of you here for a while; EASA, The FAA, and Boeing agreed several weeks ago on a list of issues to be addressed. It was reported at that time that the list under discussion included 5 items - but, not how these 5 items were to be resolved other than the MCAS and just identified computer software issue had to be resolved for re-certification. The above issue with the control cables and a possible failure related to an uncontained engine failure is not a new or unknown issue. I have not heard anyone mention the other 3 items on the list for at least discussion- or what would be required to address them. Just that Boeing feels that they will have everything resolved by some time in September, for submitting to the regulators.

In reality, there are dozens of lessor items that could be problems at times that have been accepted by the regulators. I am quite sure that the same is true of any other aircraft out there. No one builds a perfect aircraft, and no one is required to. They are only to meet a certain estimated rate of severity and failure probability. The current generation of aircraft is much safer than the older generations of aircraft because of the current regulatory system. Go back and look at the failure rates of the 707, 727, and aircraft of similar age from other companies. The entire industry has come a long way in aircraft safety since then.

As discussed long ago, the key failure with MCAS version 1 was an inadequate Failure Mode and Effects Analysis (FMEA). It seems that no one anticipated the overall system failure mode that occurred with the MCAS (although it could have been an inadequate estimation of the effects and their severity/probability).

That is what went wrong with the 738Max and MCAS - not choice of technology, etc. Had the FMEA properly identified the failure mode that happened and the severity/probability then Boeing would have done something different in order to have a FMEA that met the severity/probability requirements, and at least MCAS would not likely be a contributing factor in the Lions Air crash (and I'm not sure where it will fall in the Ethiopian crash: Remember in Lion Air's case that two pilots had successfully controlled the aircraft with the MCAS problem - the aircraft was flyable with the right control actions; and then a 3rd pilot apparently did not perform any of those corrective control actions and the aircraft crashed: I'm not sure if the Ethiopian aircraft was flyable with its problems as the preliminary report released a lot less real information).

If the Bloomberg article (Post 2869 by 'art") is to be believed: The software issue that the FAA identified was listed in the FMEA; but, apparently its effect and severity/probability was underestimated. It seems to me that the FAA apparently had a lead to that issue by the FMEA, and apparently decided to test it. It turned out to be worse the estimated in the FMEA.

FMEAs are not the easiest thing to do. First thing you start with a known checklist based on the history of failures for each kind of component and system. Personal experience puts these checklist at 20-30 pages long for anything except a simple part; and they are twice the length of 15 years ago because of failures that have occurred (and Boeing MCAS will certainly add some new questions to future FMEAs for similar systems). The tough part is that each section of a FMEA then ask if you can think of any failure mode not covered in the section above (Each section of a FMEA will discuss a specific kind/type of failure). What else could go wrong?... Now you have to engage a lot of thinking power - and it's not easy to think up of failure modes that have not yet occurred (sometimes it is done; but the vast majority of the FMEA list is from actual failures in the past).

Once a possible failure mode is established, then an estimation of the severity of the failure on the system or aircraft, and an estimated probably. None of those estimates in an exact science except for the worst obvious failures (wing falls off aircraft - results and severity obvious); and people do their best - and yes at time mis-estimate something (one of the great questions: How do you actually estimate probability and severity?... The industry has established guidelines - but, no one actually knows the real answers in many cases; and you cannot test everything and certainly cannot test things to on the order of a billion cycles to actually get statistically valid failure result statistics).

Personal experience also is that at least 5 different independent people review FMEAs before being submitted to a regulator (at least in the Nuclear industry; and I understand the Aerospace industry uses essentially the same approval process). I have been part of the review team for such FMEAs before (but have never filled out out from scratch). In 1 case I questioned an item that resulted in about a 1 week research and debate with much more clarification on the issue to all parties (I don't remember if it changed the answers on the form or not); and everyone agreed that my question was a good one.

Ultimately, the regulator accepts the FMEA's as they are the document that actually says a part, system, etc. meets the required regulatory requirements for safety appropriate to its function.

I know that the big change in the regulatory process is moving forward for their to be an independent 3rd party to review the FMEA's and report to the FAA, and the manufacture, their conclusions. That should minimize future major misses as occurred on the 738Max MCAS.

I am quite sure that a FMEA was done on the control cable question in relationship to an uncontained engine failure; and even if its one of the other 3 items on the list; no one has indicated any hardware changes will be needed for Boeing to respond to the list of items that EASA, FAA, and Boeing has agreed to.

So relax a bit: Let Boeing finish their process and get it reviewed and approved by the regulators - and at that point I suspect that the 738Max will actually have faced more regulatory scrutiny and potential testing than any Airbus - and will be at least as safe.

You all have a great day,
 
Caryjack
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 4:19 am

maverick4002 wrote:
TaromA380 wrote:
I remember that back in March after the ET crash, the FAA was repeating its conviction that the MAX is safe and it won’t ground it, even after the finding that MCAS was again involved and despite being grounded by all the other relevant NAAs. Then, out of nowhere, Trump stepped in and decreed the grounding over the FAA itself.
He could as well tweet that the Max is okay back then. To outsider me, the U.S. president doesn’t look like a weak link in the responsibilities chain in this particular aviation affair. Quite the contrary.


You cannot be serious with this comment

That's the way I remember it.
https://www.usatoday.com/story/news/pol ... 152157002/
 
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bgm
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 5:31 am

flyingphil wrote:
Just when I thought there may be light at the end of the tunnel.. an issue with the rudder cables.
https://www.seattletimes.com/nation-wor ... oversight/

“Early on, engineers at the FAA discovered a problem with one of the most important new features of the MAX: its engines. The MAX, the latest version of the 50-year-old 737, featured more fuel-efficient engines, with a larger fan and a high-pressure turbine. But the bigger, more complex engines could do more damage if they broke apart midair.

The FAA engineers were particularly concerned about pieces hitting the cables that control the rudder, according to five people with knowledge of the matter and internal agency documents. A cable severed during takeoff would make it difficult for pilots to regain control, potentially bringing down the jet.... “


Good luck trying to fix that with a software update. :sarcastic:
If you hate wearing a mask, you’re really going to hate using a ventilator.
 
marcelh
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 5:44 am

XRAYretired wrote:
. But we are talking extremely remote probabilities here.

Ray

True. The problem is that when it happens, it’s with the 737 used to be called “MAX” and “making a safe plane even safer”.
 
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BoeingVista
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 6:06 am

bgm wrote:
flyingphil wrote:
Just when I thought there may be light at the end of the tunnel.. an issue with the rudder cables.
https://www.seattletimes.com/nation-wor ... oversight/

“Early on, engineers at the FAA discovered a problem with one of the most important new features of the MAX: its engines. The MAX, the latest version of the 50-year-old 737, featured more fuel-efficient engines, with a larger fan and a high-pressure turbine. But the bigger, more complex engines could do more damage if they broke apart midair.

The FAA engineers were particularly concerned about pieces hitting the cables that control the rudder, according to five people with knowledge of the matter and internal agency documents. A cable severed during takeoff would make it difficult for pilots to regain control, potentially bringing down the jet.... “


Good luck trying to fix that with a software update. :sarcastic:


How long would this fix take, a year? And this is something that FAA or EASA can insist is fixed at any time (but the first uncontained engine failure will make this a certainty) so Boeing have made themselves hostages to fortune, the MAX program can be brought to an effective end by regulators at any point.
BV
 
MartijnNL
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 7:25 am

Draken21fx wrote:
Did they fly with flaps extended by any chance in order for the MCAS not to kick in?

I don't know. A Dutch news report stated the plane was flown relatively low and slow to avoid any MCAS related problems. No word on using the flaps. Maybe someone else has the answer to your question.
 
uta999
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 7:53 am

I wonder if plan B, the nuclear option would be to cancel the MAX, and then swap the FAL at Renton to build the Airbus A320/321 NEO.

I am not joking either. Boeing would have to merge with Airbus, things are that bad.
Your computer just got better
 
NDiesel
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 8:25 am

I've been a frequent flyer for years like most of you, having flown the 737 Classic/NG hundreds of times and always enjoyed it. But I sincerely hope (knowing this probably won't be the case) the MAX never flies again. Reading all these posts, learning about issue upon issue, all I can think about is the 346 people who had their lives stolen from them, scared beyond belief while being stuck on a faulty machine nosediving into the ground because Boeing intentionally cut corners. It's unacceptable. For that reason alone, this program deserves to fail and BCA should suffer the consequences. Those guys were regular passengers and crew, just like us when we're flying. No different.

Knowing what the folks on this forum now know - would you really fly on a MAX in the future? Would you feel absolutely certain that ALL potentially lethal faults have been identified and fixed? I wouldn't. And this is coming from a lifelong Boeing fanboy.
Delta MD-11 JFK-CDG - Upon sunrise I fell in love with aviation
 
oschkosch
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 8:26 am

It just keeps getting worse!

https://www.businessinsider.de/boeing-7 ... ?r=US&IR=T

The Federal Aviation Administration didn't understand the risks of the flight-control system in Boeing's 737 Max before the first of its fatal accidents last October, according to a new report in The New York Times.
The engineers charged with overseeing the safety of the automated software had little experience with such systems, according to the report.
The FAA allowed Boeing to assess the safety of the system itself, The Times reported.
Boeing largely kept the agency in the dark about the importance and risks of the system and didn't give the FAA an updated safety assessment after making a significant change to the software late in the plane's development, the report said.


As the plane got closer to production, Boeing made a big change to the MCAS system, allowing it to turn on at low speeds and to move the tail stabilizer by as much as 2.5 degrees each time it turned on, according to the report. Previously, the system could only activate at high speeds and could only move the stabilizer by 0.6 degrees a time.

Boeing didn't provide the FAA with an updated safety assessment of the flight-control system after making the changes and the two new agency engineers were unaware that the software could move the tail by 2.5 degrees, according to the report.

After the first crash of the 737 Max last October, FAA officials found they didn't understand and had little documentation about the workings of the MCAS system, The Times reported.

:stirthepot: :airplane: "This airplane is designed by clowns, who in turn are supervised by monkeys" :airplane: :stirthepot:
 
giblets
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 9:19 am

oschkosch wrote:
It just keeps getting worse!

https://www.businessinsider.de/boeing-7 ... ?r=US&IR=T


As the plane got closer to production, Boeing made a big change to the MCAS system, allowing it to turn on at low speeds and to move the tail stabilizer by as much as 2.5 degrees each time it turned on, according to the report. Previously, the system could only activate at high speeds and could only move the stabilizer by 0.6 degrees a time.

Boeing didn't provide the FAA with an updated safety assessment of the flight-control system after making the changes and the two new agency engineers were unaware that the software could move the tail by 2.5 degrees, according to the report.

After the first crash of the 737 Max last October, FAA officials found they didn't understand and had little documentation about the workings of the MCAS system, The Times reported.



This has been known for some time,



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flyingphil
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 9:21 am

This is the first time I have seen the issue of protection for the rudder cables raised (yes, it's 2019 and Boeing are still using cables like in a Cessna 150)

In turboprops the fuselage normally has extra protection around the propeller arc. Maybe that's what they are suggesting?

There was that Southwest incident last year when engine debris penetrated the fuselage.. but it's very rare.

I'll give it until October when you will see airlines and lessors starting to cancel orders.. How much for a COMAC C-919 or an IRKUT MC-21? Trump would love that ;)

"The FAA engineers were particularly concerned about pieces hitting the cables that control the rudder, according to five people with knowledge of the matter and internal agency documents. A cable severed during takeoff would make it difficult for pilots to regain control, potentially bringing down the jet.... “
 
giblets
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 10:00 am

BoeingVista wrote:
bgm wrote:
flyingphil wrote:
Just when I thought there may be light at the end of the tunnel.. an issue with the rudder cables.
https://www.seattletimes.com/nation-wor ... oversight/

“Early on, engineers at the FAA discovered a problem with one of the most important new features of the MAX: its engines. The MAX, the latest version of the 50-year-old 737, featured more fuel-efficient engines, with a larger fan and a high-pressure turbine. But the bigger, more complex engines could do more damage if they broke apart midair.

The FAA engineers were particularly concerned about pieces hitting the cables that control the rudder, according to five people with knowledge of the matter and internal agency documents. A cable severed during takeoff would make it difficult for pilots to regain control, potentially bringing down the jet.... “


Good luck trying to fix that with a software update. :sarcastic:



Also new to me, other than being a bit bigger, what else is increasing the risk so much?! Does moving the engines forward put the danger area somewhere the cables are not protected?



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enzo011
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 10:34 am

2175301 wrote:
That is what went wrong with the 738Max and MCAS - not choice of technology, etc. Had the FMEA properly identified the failure mode that happened and the severity/probability then Boeing would have done something different in order to have a FMEA that met the severity/probability requirements, and at least MCAS would not likely be a contributing factor in the Lions Air crash (and I'm not sure where it will fall in the Ethiopian crash: Remember in Lion Air's case that two pilots had successfully controlled the aircraft with the MCAS problem - the aircraft was flyable with the right control actions; and then a 3rd pilot apparently did not perform any of those corrective control actions and the aircraft crashed: I'm not sure if the Ethiopian aircraft was flyable with its problems as the preliminary report released a lot less real information).


I don't recall two pilots successfully controlling the Lion Air aircraft, how do you get to that?


2175301 wrote:
So relax a bit: Let Boeing finish their process and get it reviewed and approved by the regulators - and at that point I suspect that the 738Max will actually have faced more regulatory scrutiny and potential testing than any Airbus - and will be at least as safe.


Do you think the scrutiny that Boeing has had with the MAX will me more than the 787 and A350 as new designs?
 
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LTU330
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 10:40 am

MartijnNL wrote:
Draken21fx wrote:
Did they fly with flaps extended by any chance in order for the MCAS not to kick in?

I don't know. A Dutch news report stated the plane was flown relatively low and slow to avoid any MCAS related problems. No word on using the flaps. Maybe someone else has the answer to your question.


....and if you look at the Flight track on FR24 it was not permitted to transit German Airspace. It flew right around the border (more or less).
 
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par13del
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 11:38 am

BoeingVista wrote:
but the first uncontained engine failure will make this a certainty).

The quote in the article said concerned, you have now made it a certainty.
 
Draken21fx
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 11:39 am

LTU330 wrote:
MartijnNL wrote:
Draken21fx wrote:
Did they fly with flaps extended by any chance in order for the MCAS not to kick in?

I don't know. A Dutch news report stated the plane was flown relatively low and slow to avoid any MCAS related problems. No word on using the flaps. Maybe someone else has the answer to your question.


....and if you look at the Flight track on FR24 it was not permitted to transit German Airspace. It flew right around the border (more or less).


Yes Germans do not allow 737 Max ferry flights over their territory.
 
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par13del
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 11:41 am

enzo011 wrote:
I don't recall two pilots successfully controlling the Lion Air aircraft, how do you get to that?

The Lion Air flight that successfully dealt with MCAS had 3 pilots in the cockpit, I do not recall reading that at any time he took over the controls, what I did read was that he provided advise which was followed, so are we into semantics...
 
JHwk
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 12:59 pm

NDiesel wrote:
Knowing what the folks on this forum now know - would you really fly on a MAX in the future?

Having driven over countless bridges before over the years, would you drive over one that was built by the lowest bidder?

For me, the issue is that the regulatory agencies need to rebuild trust; another crash would have a huge impact on trust in civil aviation for a long time; nobody can afford that.
 
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seahawk
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 12:59 pm

giblets wrote:
oschkosch wrote:
It just keeps getting worse!

https://www.businessinsider.de/boeing-7 ... ?r=US&IR=T


As the plane got closer to production, Boeing made a big change to the MCAS system, allowing it to turn on at low speeds and to move the tail stabilizer by as much as 2.5 degrees each time it turned on, according to the report. Previously, the system could only activate at high speeds and could only move the stabilizer by 0.6 degrees a time.

Boeing didn't provide the FAA with an updated safety assessment of the flight-control system after making the changes and the two new agency engineers were unaware that the software could move the tail by 2.5 degrees, according to the report.

After the first crash of the 737 Max last October, FAA officials found they didn't understand and had little documentation about the workings of the MCAS system, The Times reported.



This has been known for some time,



Sent from my iPhone using Tapatalk


The tone changed though. The blame game has started and it looks like the FAA is now looking at either admitting incompetence or blaming Boeing top have tricked them.
 
2175301
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 2:46 pm

par13del wrote:
enzo011 wrote:
I don't recall two pilots successfully controlling the Lion Air aircraft, how do you get to that?

The Lion Air flight that successfully dealt with MCAS had 3 pilots in the cockpit, I do not recall reading that at any time he took over the controls, what I did read was that he provided advise which was followed, so are we into semantics...


That's not what I meant: Without looking up the exact details my memory of the Lion Air crash is that:

1) The flight on the day before; the pilot of the aircraft successfully dealt with the issue by stabilizing the aircraft and turning off the MCAS system. Yes, there was a 3rd pilot in the cockpit at the time that helped.

2) The day of the flight that crashed; the pilot in command was successfully dealing with the issue by manually inputting corrections every time the MACS auto trimmed the aircraft down. The pilot in command was successfully flying the aircraft - even though he clearly knew he had a problem; and a big enough problem to decide to return to land the aircraft.

The pilot in command then turned the controls over to the co-pilot for that return and landing; and my memory is that the copilot did not perform any corrective control inputs to counteract the malfunctioning MCAS/Flight Computer system - and the flight crashed.

My memory is that the Lion Air Crash thread had a huge discussion about why apparently did the copilot not do the same kind of flight control corrections as the pilot had been doing once the preliminary report was issued and the released data showed both the MCAS initiated changes and the manual initiated changes.

There was also a discussion in that thread about why the pilots of the flight the day of the crash apparently was not told of the problems the day before and the corrective actions taken to safely fly the aircraft.

Thus my statement that 2 pilots had successfully dealt with the MCAS issue and flown the aircraft. Those 2 pilots were flying a plane with an issue; but, they were successfully retaining overall control of the flight. Obviously the 3rd pilot in this sequence above did not successfully deal with the MCAS issues and the flight crashed.

Have a great day,
 
2175301
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 3:05 pm

enzo011 wrote:
2175301 wrote:
So relax a bit: Let Boeing finish their process and get it reviewed and approved by the regulators - and at that point I suspect that the 738Max will actually have faced more regulatory scrutiny and potential testing than any Airbus - and will be at least as safe.


Do you think the scrutiny that Boeing has had with the MAX will me more than the 787 and A350 as new designs?


Yes. I think that after the MCAS/Flight Computer issues are fixed to the satisfaction of the Regulators, that it (flight control time/stabilizer control and management) will have been scrutinized in more detail than the 787 and A350. Every one has been called to task on the failures to catch this issue both within Boeing and within the FAA; and all parties are now applying a lot more efforts in this area than before. EASA was involved in the investigation why this happened (failure to properly identify/classify in the system FMEA); and the recommended change the EASA asked for (3rd party independent review of the FMEA's) is not something that has been previously normally done by EASA either; and will now be standard for both EASA and FAA.

I've lived this type of scenario in the Nuclear world; where the plant I worked at had the most scrutinized Auxiliary Feed water System in the US nuclear fleet; not to mention that my plant developed the best "corrective action" and "modification package review" programs in the industry due to the issues at our plant with that system. The entire rest of the industry and the NRC learned from us and the issues that occurred (again a failure at the FMEA level). That period when we were under constant regulatory scrutiny were very intense...

I've got some contacts in the Aerospace world - and know that essentially the process and regulatory processes are essentially the same between aerospace and nuclear, even if the standards and the technical details of what is being regulated is a bit different (there are different acceptable failure rates and factors of safety). Interestingly, the commercial software program we used in our plant for component/part and system probability of failure is also sold to a number of aerospace companies.

Have a great day,
 
XRAYretired
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 3:14 pm

2175301 wrote:
par13del wrote:
enzo011 wrote:
I don't recall two pilots successfully controlling the Lion Air aircraft, how do you get to that?

The Lion Air flight that successfully dealt with MCAS had 3 pilots in the cockpit, I do not recall reading that at any time he took over the controls, what I did read was that he provided advise which was followed, so are we into semantics...


That's not what I meant: Without looking up the exact details my memory of the Lion Air crash is that:

1) The flight on the day before; the pilot of the aircraft successfully dealt with the issue by stabilizing the aircraft and turning off the MCAS system. Yes, there was a 3rd pilot in the cockpit at the time that helped.

2) The day of the flight that crashed; the pilot in command was successfully dealing with the issue by manually inputting corrections every time the MACS auto trimmed the aircraft down. The pilot in command was successfully flying the aircraft - even though he clearly knew he had a problem; and a big enough problem to decide to return to land the aircraft.

The pilot in command then turned the controls over to the co-pilot for that return and landing; and my memory is that the copilot did not perform any corrective control inputs to counteract the malfunctioning MCAS/Flight Computer system - and the flight crashed.

My memory is that the Lion Air Crash thread had a huge discussion about why apparently did the copilot not do the same kind of flight control corrections as the pilot had been doing once the preliminary report was issued and the released data showed both the MCAS initiated changes and the manual initiated changes.

There was also a discussion in that thread about why the pilots of the flight the day of the crash apparently was not told of the problems the day before and the corrective actions taken to safely fly the aircraft.

Thus my statement that 2 pilots had successfully dealt with the MCAS issue and flown the aircraft. Those 2 pilots were flying a plane with an issue; but, they were successfully retaining overall control of the flight. Obviously the 3rd pilot in this sequence above did not successfully deal with the MCAS issues and the flight crashed.

Have a great day,

Suggest you go back and read the reports and the thread rather than relying on a partial memory to make points that are not quite correctly based. Otherwise its re-writing history to suit an argument that we have all been through before.
https://reports.aviation-safety.net/201 ... MINARY.pdf
https://reports.aviation-safety.net/201 ... PRELIM.pdf

Ray
 
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flyingphil
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 3:58 pm

XRAYretIred is right.

I thought we had moved on from trying to blame the dead pilots months ago. Even Sully has doubts he could have saved the plane. MCAS was unheard of until the Lion Air crash. If they had been flying NG's they would still be alive.

I am more interested in why the FAA is so interested in protecting the rudder cables all of a sudden. No doubt this information was leaked for a reason. Draw your own conclusions.. is the FAA preparing to announce more bad news for Boeing? This saga shows no signs of ending.
 
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 4:15 pm

seahawk wrote:
The tone changed though. The blame game has started and it looks like the FAA is now looking at either admitting incompetence or blaming Boeing top have tricked them.

I think the media's tone is changing, in that the NYT article named a lot of names of FAA officials.

NYT pointed out that the current head of safety at FAA was pushing for high amounts of delegation to Boeing, installed personnel in their "Boeing" office that were deferential with respect to that policy, then left the FAA to join an industry lobbying group supported by Boeing, and now has returned to FAA as head of safety ( ref: https://www.faa.gov/about/key_officials/ ).

They also chose to name the FAA manager who decided to delegate MCAS approval to Boeing and the manager who chose to take Boeing's side on the rudder cable issue.

Seems NYT is making things a lot more personal than they had in the past.

Maybe they have more confidence in their sources, or maybe they have decided they want to generate more heat/buzz?
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IADFCO
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 4:38 pm

When I read of the "new" rudder issue, I thought United 232.

Imagine that you are FAA, it's 1975 (or whenever), you are certifying the DC-10, and one of your safety engineers notices that the three hydraulic systems converge in one place, and could all be severed by the failure of a fan disk. Would: "Nah, it won't ever happen, and it would be too expensive for MD to fix it anyway" be an acceptable answer?
 
2175301
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 4:38 pm

XRAYretired wrote:
2175301 wrote:
par13del wrote:
The Lion Air flight that successfully dealt with MCAS had 3 pilots in the cockpit, I do not recall reading that at any time he took over the controls, what I did read was that he provided advise which was followed, so are we into semantics...


That's not what I meant: Without looking up the exact details my memory of the Lion Air crash is that:

1) The flight on the day before; the pilot of the aircraft successfully dealt with the issue by stabilizing the aircraft and turning off the MCAS system. Yes, there was a 3rd pilot in the cockpit at the time that helped.

2) The day of the flight that crashed; the pilot in command was successfully dealing with the issue by manually inputting corrections every time the MACS auto trimmed the aircraft down. The pilot in command was successfully flying the aircraft - even though he clearly knew he had a problem; and a big enough problem to decide to return to land the aircraft.

The pilot in command then turned the controls over to the co-pilot for that return and landing; and my memory is that the copilot did not perform any corrective control inputs to counteract the malfunctioning MCAS/Flight Computer system - and the flight crashed.

My memory is that the Lion Air Crash thread had a huge discussion about why apparently did the copilot not do the same kind of flight control corrections as the pilot had been doing once the preliminary report was issued and the released data showed both the MCAS initiated changes and the manual initiated changes.

There was also a discussion in that thread about why the pilots of the flight the day of the crash apparently was not told of the problems the day before and the corrective actions taken to safely fly the aircraft.

Thus my statement that 2 pilots had successfully dealt with the MCAS issue and flown the aircraft. Those 2 pilots were flying a plane with an issue; but, they were successfully retaining overall control of the flight. Obviously the 3rd pilot in this sequence above did not successfully deal with the MCAS issues and the flight crashed.

Have a great day,

Suggest you go back and read the reports and the thread rather than relying on a partial memory to make points that are not quite correctly based. Otherwise its re-writing history to suit an argument that we have all been through before.
https://reports.aviation-safety.net/201 ... MINARY.pdf
https://reports.aviation-safety.net/201 ... PRELIM.pdf

Ray


This specific discussion is about the Lion Air Crash - and does not involve the Ethiopian crash. In a post above the previous one under discussion here I state essentially that I have not formed any opinions on the Ethiopian crash.

The preliminary report for the 2018 crash in my opinion validates my point number 1) The pilots of the previous day's flight appropriately handled the situation with the failure of the MCAS/flight control computer system.

I admit that the 2nd point is at best only possibly partially validated by the preliminary report. It does show that for much of the flight once the MCAS system started to automatically trim down, that there were essentially matching manual trip ups to maintain basic flight stability, including pitch trim levels. Then after 22:30:53 in the last about 1.5 minutes hat there were very few (and clearly not matching) manual inputs to offset the automatic trim down commands. Pitch trim went low, altitude was lost with an increas in airspeed (dramatically) and the crash occurred.

Up to in the range of 22:30:53 the pilot flying the aircraft was maintaining essential control, even though they knew they had problems (clearly communicated by the control tower transcripts). After that time they were not.

The preliminary report was issued before the CVR recorders were located. It does not indicate who was at the controls of the aircraft (or at least I did not see that indicated). So, there is no proof one way or another about my belief that there was a switch of the pilot flying during this time (that one adequately controlled the aircraft, and the next one did not).

The Lion Air Crash thread included a lot of information (some factual and very useful, much speculation - of various degrees of plausibility) that was not in the preliminary report, and includes information from after the CVR was located. It will take time to dig through that thread and find why I believe what I currently believe (or identify that my belief was incorrect). That will take some time to do. I will work on it in my free time. If others know if any information in the Lion Air Crash threa, or related thread, about a change of pilots flying the Lion Air flight - and any changes: That would speed things up.

Have a great day,
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 5:41 pm

Before we go crazy on the rudder cable issue, it would help to find out if Boeing added any protection. The article says they didn't want to add redundant cables or make the rudder FBW due to commonality (although it was fine to go to FBW spoilers). The article doesn't say if they added protection to what should be a very small area of concern.
 
XRAYretired
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 5:43 pm

2175301 wrote:
XRAYretired wrote:
2175301 wrote:

That's not what I meant: Without looking up the exact details my memory of the Lion Air crash is that:

1) The flight on the day before; the pilot of the aircraft successfully dealt with the issue by stabilizing the aircraft and turning off the MCAS system. Yes, there was a 3rd pilot in the cockpit at the time that helped.

2) The day of the flight that crashed; the pilot in command was successfully dealing with the issue by manually inputting corrections every time the MACS auto trimmed the aircraft down. The pilot in command was successfully flying the aircraft - even though he clearly knew he had a problem; and a big enough problem to decide to return to land the aircraft.

The pilot in command then turned the controls over to the co-pilot for that return and landing; and my memory is that the copilot did not perform any corrective control inputs to counteract the malfunctioning MCAS/Flight Computer system - and the flight crashed.

My memory is that the Lion Air Crash thread had a huge discussion about why apparently did the copilot not do the same kind of flight control corrections as the pilot had been doing once the preliminary report was issued and the released data showed both the MCAS initiated changes and the manual initiated changes.

There was also a discussion in that thread about why the pilots of the flight the day of the crash apparently was not told of the problems the day before and the corrective actions taken to safely fly the aircraft.

Thus my statement that 2 pilots had successfully dealt with the MCAS issue and flown the aircraft. Those 2 pilots were flying a plane with an issue; but, they were successfully retaining overall control of the flight. Obviously the 3rd pilot in this sequence above did not successfully deal with the MCAS issues and the flight crashed.

Have a great day,

Suggest you go back and read the reports and the thread rather than relying on a partial memory to make points that are not quite correctly based. Otherwise its re-writing history to suit an argument that we have all been through before.
https://reports.aviation-safety.net/201 ... MINARY.pdf
https://reports.aviation-safety.net/201 ... PRELIM.pdf

Ray


This specific discussion is about the Lion Air Crash - and does not involve the Ethiopian crash. In a post above the previous one under discussion here I state essentially that I have not formed any opinions on the Ethiopian crash.

The preliminary report for the 2018 crash in my opinion validates my point number 1) The pilots of the previous day's flight appropriately handled the situation with the failure of the MCAS/flight control computer system.

I admit that the 2nd point is at best only possibly partially validated by the preliminary report. It does show that for much of the flight once the MCAS system started to automatically trim down, that there were essentially matching manual trip ups to maintain basic flight stability, including pitch trim levels. Then after 22:30:53 in the last about 1.5 minutes hat there were very few (and clearly not matching) manual inputs to offset the automatic trim down commands. Pitch trim went low, altitude was lost with an increas in airspeed (dramatically) and the crash occurred.

Up to in the range of 22:30:53 the pilot flying the aircraft was maintaining essential control, even though they knew they had problems (clearly communicated by the control tower transcripts). After that time they were not.

The preliminary report was issued before the CVR recorders were located. It does not indicate who was at the controls of the aircraft (or at least I did not see that indicated). So, there is no proof one way or another about my belief that there was a switch of the pilot flying during this time (that one adequately controlled the aircraft, and the next one did not).

The Lion Air Crash thread included a lot of information (some factual and very useful, much speculation - of various degrees of plausibility) that was not in the preliminary report, and includes information from after the CVR was located. It will take time to dig through that thread and find why I believe what I currently believe (or identify that my belief was incorrect). That will take some time to do. I will work on it in my free time. If others know if any information in the Lion Air Crash threa, or related thread, about a change of pilots flying the Lion Air flight - and any changes: That would speed things up.

Have a great day,

So apart from repeating the analyses that we been through before, what is the point you wish to make?


Ray
 
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sassiciai
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 7:28 pm

Xray,

He just wants to hope that you have a great day!

It is a tad irritating those posters who have a "signature" on a.net. This one often fails to fall into line with his posts, this "have a great day" is a very American greeting even if the topic preceding it is much more solemn

But then there are others who drone on in their signature with all the aircraft they ever saw, flew on, liked, took a photo of, or every origin:destination they ever flew! I only hope that they enjoy their posts themselves!

I am taken aback and even amused at the outcry that the 737 still has cables from the cockpit to the flight control surfaces! Yes, it is that old, and in order for it to be a great grandchild of the first one, it must keep its cables!

With that said, the concept of an uncontrolled engine failure on a Max all of a sudden takes on a whole new level of horror! I am short of historical detail of where and when, but it reminds me of the DC-10 with severed cables trying to land in Sioux City. I don't want to be there with Max, thanks! I'll wait for the next non-Max flight, I think! If things pan out as planned and the Max gets recertified, then I am done with Ryanair for good in Europe for me and my family!
 
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 7:34 pm

XRAYretired wrote:
So apart from repeating the analyses that we been through before, what is the point you wish to make?

Before we went down the tangent of quibbling over the repeated analyses, the main point was:

2175301 wrote:
So relax a bit: Let Boeing finish their process and get it reviewed and approved by the regulators - and at that point I suspect that the 738Max will actually have faced more regulatory scrutiny and potential testing than any Airbus - and will be at least as safe.
Wake up to find out that you are the eyes of the world
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IADFCO
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 7:54 pm

planecane wrote:
Before we go crazy on the rudder cable issue, it would help to find out if Boeing added any protection. The article says they didn't want to add redundant cables or make the rudder FBW due to commonality (although it was fine to go to FBW spoilers). The article doesn't say if they added protection to what should be a very small area of concern.


"F.A.A. managers conceded that the Max “does not meet” agency guidelines “for protecting flight controls,” according to an agency document." (from the NYT/Seattle Times article)

So, whatever this "protection" might consist of, it would appear that the issue remains.
 
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bgm
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 7:58 pm

sassiciai wrote:
With that said, the concept of an uncontrolled engine failure on a Max all of a sudden takes on a whole new level of horror! I am short of historical detail of where and when, but it reminds me of the DC-10 with severed cables trying to land in Sioux City. I don't want to be there with Max, thanks! I'll wait for the next non-Max flight, I think! If things pan out as planned and the Max gets recertified, then I am done with Ryanair for good in Europe for me and my family!


You can watch the documentary here: https://www.youtube.com/watch?v=r3jRfXo7uck

They lost all 3 hydraulic lines (which ran next to the #2 engine).
If you hate wearing a mask, you’re really going to hate using a ventilator.
 
sphealey
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 8:10 pm

This is the first time I have seen the issue of protection for the rudder cables raised (yes, it's 2019 and Boeing are still using cables like in a Cessna 150)
Electrical control cables can be cut by debris from an engine failure just as easily as wire rope cables - perhaps more easily - as was seen in the Qantas 32 incident.

In general however: is withstanding uncontained engine failure now a design basis requirement? Because if so there are a lot of designs currently flying that are in trouble. The debris from the rotor failure on Qantas 32 came within about 5cm of severing the main wing spar for example. It has always been my understanding that while mitigation of uncontained failure should be included where possible such an incident is not expected to be survivable (though fortunately in practice it almost always has been, thanks to mitigation and redundancy).
 
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 8:23 pm

Wake up to find out that you are the eyes of the world
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Wake now, discover that you are the song that the morning brings
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IADFCO
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 8:33 pm

Interesting link (it includes additional links to pertinent certification requirements)

https://www.skybrary.aero/index.php/Unc ... ne_Failure
 
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flyingphil
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 9:18 pm

Revelation wrote:


At the risk of reading too much into this... how come only Germany has banned 737MAX overflights?
Are we seeing the supposed 'lockstep' of regulators breaking down and the 737MAX being judged as airworthy on a country by country basis?
Germany's neighbouring countries are all members of EASA (European Aviation Safety Agency)

Oh well... I wonder what snippets of information will leak out this week?
 
OEMInsider
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 9:20 pm

sphealey wrote:
This is the first time I have seen the issue of protection for the rudder cables raised (yes, it's 2019 and Boeing are still using cables like in a Cessna 150)
Electrical control cables can be cut by debris from an engine failure just as easily as wire rope cables - perhaps more easily - as was seen in the Qantas 32 incident.

In general however: is withstanding uncontained engine failure now a design basis requirement? Because if so there are a lot of designs currently flying that are in trouble. The debris from the rotor failure on Qantas 32 came within about 5cm of severing the main wing spar for example. It has always been my understanding that while mitigation of uncontained failure should be included where possible such an incident is not expected to be survivable (though fortunately in practice it almost always has been, thanks to mitigation and redundancy).


Yes, Uncontained Engine Rotor Failure is a key requirement for all large aircraft (CS25/FAR25). In fact its one of the most important considerations when designing an aircraft, particularly the wings. The general rule is that 95% of UERF events must not be Catastrophic (i.e. loss of aircraft). Therefore, only 5% of the possible trajectories of rotors (which are assumed to be 1/3 disc fragments) can cause damage which would cause a crash. Any system (electrical wire, control cable, structural attachment) must either be located outside the zone of possible impacts, have a redundant backup such that only one can be hit at a time or by able to continue to do its job after being hit.

The most dangerous debris (1/3 disc fragment) can leave the engine in any direction (when viewed from the front), but only within a 5degree cone when viewed from the top (due to the axis they were spinning on). Shielding or armour is possible but not used - these fragments have huge energy and are normally considered to destroy everything in their path. It would take several inches of steel to protect against them (think tank armour - literally). Not good for weight optimisation.

Electrical wires, hydraulic and fuel lines are duplicated in the wing - one on the leading edge, one on the trailing edge, to ensure we have redundancy. Anything really close to the engine (where you can't separate them) will be part of the 5% allowed to be catastrophic. One fragment hitting the other engine would also be considered catastrophic.

For the rudder control cables - none of this is new (UERF events used to be much more common). If you look at a front view of an aircraft, to take out the rudder control cables (assuming they are in the bilge area), the same fragment would probably hit the other engine anyway - so already catastrophic. IMO I don't think the cables issue is a big one. It might be catastrophic, but allowed as part of the 5% chance.
https://imgur.com/a/Wrs5lis

Meeting the 95% rule is hard, but that's why not many companies build planes like this. The A380 event revealed a mistake - a few wires in the fuselage were inside the impact zone when thee routes were not segregated (I am told). This has been corrected. These rules have evolved over the years, and new designs have to do things old ones don't (grandfathering again).
 
strfyr51
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 9:32 pm

flyingphil wrote:
capshandler wrote:
If I were Boeing I’d ask Airbus to jump in and help solve the problem. The’ve got experience with FBW and software based flying models. And If I were Airbus I’d jump in immediately. It’s in interest of both for so many reasons. They should work closely and secretly and make the 737Max fly again asap.


Boeing has lots of experience of FBW on its other planes.. but stuck with the old cables and pulleys for the 737MAX.
Maybe Embraer could pitch in, but there is not much you can do with such an old design.

I hope someone at Boeing is looking at doomsday scenarios .. and ‘what if’s’
What if the FAA want a new trim wheel that does not require a bodybuilder to operate it
What if they want a third AoA vane
What if they want aerodynamic changes, vortex generators, etc, etc
Changes that will cost more than the value of the frames..

How far away are Boeing from a 737 replacement?
Here is an idea.. Boeing does a lot of business with China, the Comac C919 is already flying, it has western engines and avionics... why not partner up with them?

Anyway .. will get back in my box now :)[/quo


The VERY last thing Boeing needs to do is share data with Comac on "Anything! Boeing could transfer and scale data from the 787 to any other new model they choose! They have the aerodynamic test data and they're always down at NASA Ames in Mountain View CA. Working on More in their wind Tunnels.
What they'll need is a scaled up GTF ready for heavy weight airplanes in the 500K-650K Lbs. Max Gross arena something to change the Game Plan for Airbus and any Other Airline Airplane Builder.
 
planecane
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Re: Boeing 737MAX Grounded Worldwide Q3 2019

Sun Jul 28, 2019 10:32 pm

IADFCO wrote:
planecane wrote:
Before we go crazy on the rudder cable issue, it would help to find out if Boeing added any protection. The article says they didn't want to add redundant cables or make the rudder FBW due to commonality (although it was fine to go to FBW spoilers). The article doesn't say if they added protection to what should be a very small area of concern.


"F.A.A. managers conceded that the Max “does not meet” agency guidelines “for protecting flight controls,” according to an agency document." (from the NYT/Seattle Times article)

So, whatever this "protection" might consist of, it would appear that the issue remains.


The time context of that quote was still before certification.

MCAS is one thing but if the FAA identified something that doesn't meet their guidelines and let Boeing do nothing to mitigate the risk that is unacceptable and 100% the fault of the FAA (and this seems to have taken place under the Obama administration so let's not bring Trump into it as a distraction).

Being a highly unlikely event I'd be OK with an AD that has a solution rolled out over time but to allow the MAX to fly for 30 years with a known potential issue like that would be unacceptable. They should experiment to see if possibly adding a Kevlar shield in the most vulnerable area would mitigate the risk.

Even if the risk is 1 in 100 million flights, a simple solution could make it 1 in a billion or more.

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