Civil Aviation Development & Discussion

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Austin
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Re: Civil Aviation Development & Discussion

Postby Austin » 12 Mar 2019 23:22

The problem per say is not with Airbus but with P&W GTF engine .....The LEAP Engine on NEO has not issue and thats a CFM engine

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Re: Civil Aviation Development & Discussion

Postby Austin » 12 Mar 2019 23:26

Raveen wrote:How is it uncomfortable to fly? the seats on the MAX are wider than the Neo which as you pointed out had a LONG list of significant issues prior to this to the point where people on this forum were asking for a grounding


737 has little room to move and is clusterphobic , I dont have exp with Max but on 737-800 and 320NEO and NEO approaches near to wide body class in comfort.

Boeing should have designed a new Narrow Body in late 90's to compete with AB instead of just tinkering with a 60 design aircraft ....With MAX they tinkered with the CG and the resulting MCAS software fix so called enhanced safety to an already safe aircraft has made it worse.

They seem to have focussed too much on WIde body and left the Narrow body open to Airbus now.

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Re: Civil Aviation Development & Discussion

Postby Raveen » 12 Mar 2019 23:37

arvin wrote:Atleast Airbus GTF problem were partly remedied by shorter inspection time and stopping long overflights over water. It was in the hands of operator to do something about it. But how to they rectify a piece of code that apparently gets confused between take off nose up and stall nose up.



Speaking of software, remember the crash caused by Airbus's software overriding the pilot because a pilot's son caused it to glitch moving the stick a certain way 3 times

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Re: Civil Aviation Development & Discussion

Postby Raveen » 12 Mar 2019 23:39

Austin wrote:
Raveen wrote:How is it uncomfortable to fly? the seats on the MAX are wider than the Neo which as you pointed out had a LONG list of significant issues prior to this to the point where people on this forum were asking for a grounding


737 has little room to move and is clusterphobic , I dont have exp with Max but on 737-800 and 320NEO and NEO approaches near to wide body class in comfort.

Boeing should have designed a new Narrow Body in late 90's to compete with AB instead of just tinkering with a 60 design aircraft ....With MAX they tinkered with the CG and the resulting MCAS software fix so called enhanced safety to an already safe aircraft has made it worse.

They seem to have focussed too much on WIde body and left the Narrow body open to Airbus now.


Aah there's a ton of politics there - they wanted a clean sheet design but Southwest threatened to leave Boeing...and so we have MAX, which STILL has the widest seats in a narrow body

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Re: Civil Aviation Development & Discussion

Postby Singha » 12 Mar 2019 23:59

ANI
@ANI
Directorate General of Civil Aviation (DGCA) has taken the decision to ground the Boeing 737-MAX planes immediately.

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Re: Civil Aviation Development & Discussion

Postby Singha » 12 Mar 2019 23:59

Very reactive
No new data
Just following herd in uk

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Re: Civil Aviation Development & Discussion

Postby Singha » 13 Mar 2019 00:05

ANI
@ANI
AFP news agency: Germany and France ban Boeing 737 MAX 8 planes from their airspace.

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Re: Civil Aviation Development & Discussion

Postby Singha » 13 Mar 2019 00:05

Norway too meetoo

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Re: Civil Aviation Development & Discussion

Postby Singha » 13 Mar 2019 00:08

Turkey amd holland meetoo

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Re: Civil Aviation Development & Discussion

Postby Ashokk » 13 Mar 2019 03:25

Russia's only operator flying 737 Max, S7, grounds it's two planes.

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Re: Civil Aviation Development & Discussion

Postby ldev » 13 Mar 2019 04:16

Singha wrote:Very reactive
No new data
Just following herd in uk


In contrast to meto:

A growing number of airlines and countries around the world have temporarily grounded Boeing 737 MAX 8 planes as a precaution. Canada is not one of them.

Federal Transport Minister Marc Garneau said on Tuesday Canada will not ban the planes, despite the decision from the European nations.

“It’s important for us not to jump to conclusions, but to evaluate in a very objective and logical way what happened,” he said. “At the moment we have no information whatsoever to lead us to any hypothesis, and yet there are many possible causes of this tragic accident.”

“It was a sunny day, an experienced pilot, the plane was brand new. But we know little else,” he said
. “Flying in this country is one of the safest ways to travel. The statistics very, very clearly prove that.”

Garneau added that Canada has a very high safety recording with the Boeing 737 MAX 8, but the government is prepared to ground the jets if need be. He tweeted Tuesday afternoon that he was meeting with a “Civil Aviation Expert Panel” and that “all evidence is being evaluated in real time.”


Canada not grounding Boeing 737 MAX planes despite EU airspace ban

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Re: Civil Aviation Development & Discussion

Postby Austin » 13 Mar 2019 07:38

Ministry of Civil Aviation
@MoCA_GoI
DGCA has taken the decision to ground the Boeing 737-MAX planes immediately. These planes will be grounded till appropriate modifications and safety measures are undertaken to ensure their safe operations. (1/2)

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Re: Civil Aviation Development & Discussion

Postby Vikas » 13 Mar 2019 11:07

Singha wrote:Very reactive
No new data
Just following herd in uk


Better follow the herd than to wander off and get killed. Usually the herd is right.

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Re: Civil Aviation Development & Discussion

Postby Austin » 13 Mar 2019 11:47

EASA Suspends Boeing 737 Max Operations In and To Europe

https://www.ainonline.com/aviation-news ... and-europe

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Re: Civil Aviation Development & Discussion

Postby Sicanta » 13 Mar 2019 20:45

https://seekingalpha.com/instablog/1006 ... ng-737-max

What might be wrong with boeing 737 max 8

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Re: Civil Aviation Development & Discussion

Postby Zynda » 13 Mar 2019 21:05

I am assuming that Boeing will have to compensate airline operators for loss of revenue due to grounding of MAX fleets? Is this how it works?

I think Boeing should scrap NMA program & perhaps should refocus on developing NG Narrow Body. I am not sure how keenly airline operators are looking forward to a NMA product...

Airbus is bringing out A321XLR to compete with Boeing's proposed NMA. Boeing can do something similar i.e. design a ultra long-ranged variant of NG narrow body family for around 10,000 Km ranges which would be in the domain of NMA family.

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Re: Civil Aviation Development & Discussion

Postby Singha » 13 Mar 2019 21:21

comfort levels will be very poor with a 10,000km range narrowbody, with limited toilets and galleys.

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Re: Civil Aviation Development & Discussion

Postby Singha » 13 Mar 2019 22:01

CNN
New York (CNN Business)European discount carrier Norwegian Air is seeking compensation from Boeing for its grounded fleet of 737 Max 8 jets.

Norwegian is the first airline to say publicly it will demand that Boeing pay for lost flight time. It is expected other airlines will follow suit.
......

"It is quite obvious we will not take the cost related to the new aircraft that we have to park temporarily," said Norwegian CEO Bjørn Kjos in a recorded message to customers. "We will send this bill to those who produce this aircraft."

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Re: Civil Aviation Development & Discussion

Postby Raveen » 13 Mar 2019 22:24

Singha wrote:CNN
New York (CNN Business)European discount carrier Norwegian Air is seeking compensation from Boeing for its grounded fleet of 737 Max 8 jets.

Norwegian is the first airline to say publicly it will demand that Boeing pay for lost flight time. It is expected other airlines will follow suit.
......

"It is quite obvious we will not take the cost related to the new aircraft that we have to park temporarily," said Norwegian CEO Bjørn Kjos in a recorded message to customers. "We will send this bill to those who produce this aircraft."



They'll take a discount on future orders and move on after all this bluster

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Re: Civil Aviation Development & Discussion

Postby Austin » 13 Mar 2019 23:55

Pilots complained about the 737 Max in a federal database

https://edition.cnn.com/2019/03/13/us/p ... index.html

Pilot: Flight manual is 'inadequate and almost criminally insufficient'

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Re: Civil Aviation Development & Discussion

Postby gpurewal » 14 Mar 2019 00:02

ldev wrote:
Singha wrote:Very reactive
No new data
Just following herd in uk


In contrast to meto:

A growing number of airlines and countries around the world have temporarily grounded Boeing 737 MAX 8 planes as a precaution. Canada is not one of them.

Federal Transport Minister Marc Garneau said on Tuesday Canada will not ban the planes, despite the decision from the European nations.

“It’s important for us not to jump to conclusions, but to evaluate in a very objective and logical way what happened,” he said. “At the moment we have no information whatsoever to lead us to any hypothesis, and yet there are many possible causes of this tragic accident.”

“It was a sunny day, an experienced pilot, the plane was brand new. But we know little else,” he said
. “Flying in this country is one of the safest ways to travel. The statistics very, very clearly prove that.”

Garneau added that Canada has a very high safety recording with the Boeing 737 MAX 8, but the government is prepared to ground the jets if need be. He tweeted Tuesday afternoon that he was meeting with a “Civil Aviation Expert Panel” and that “all evidence is being evaluated in real time.”


Canada not grounding Boeing 737 MAX planes despite EU airspace ban




The Max 8 has been banned in Canada as well now, with flights of Max 8 being prohibited in Canadian Airspace.

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Re: Civil Aviation Development & Discussion

Postby saip » 14 Mar 2019 00:13

US too is grounding 737-8 and also 737-9 -- POTUS

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Re: Civil Aviation Development & Discussion

Postby saip » 14 Mar 2019 00:20

POTUS came on the air to make the announcement. He held off as long as he could. For him it is just business and cost to an US company is too much. MAGA.

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Re: Civil Aviation Development & Discussion

Postby saip » 14 Mar 2019 00:29

We do NOT have to make it, but it is the right decision -- Trump speak.

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Re: Civil Aviation Development & Discussion

Postby saip » 14 Mar 2019 01:46

I hope the black boxes are not being sent to Boeing. Where else can they be decoded?

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Re: Civil Aviation Development & Discussion

Postby nachiket » 14 Mar 2019 02:13

saip wrote:I hope the black boxes are not being sent to Boeing. Where else can they be decoded?

If the Ethiopian civil aviation agency (I do not know what it is called) does not have the capability to read them, they can be sent to the US NTSB. The NTSB is a far more independent and professional organization compared to the FAA, which as DIleep saar said is an old-boy's club with close relationships to Boeing (and other US manufacturers, when they existed). That old-boy's club mentality had already caused loss of life decades ago with the DC-10 and they haven't learned their lesson as the MCAS situation shows us.

However, as far as the Ethiopian airlines accident goes, we don't yet know that the MCAS was responsible, unlike the Lion Air crash where the cause is more clear.

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Re: Civil Aviation Development & Discussion

Postby Rishi_Tri » 14 Mar 2019 02:35

saip wrote:I hope the black boxes are not being sent to Boeing. Where else can they be decoded?


European Union Aviation Safety Agency - Cologne.

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Re: Civil Aviation Development & Discussion

Postby vasu raya » 14 Mar 2019 04:08

With the AoA sensor as a single point of failure, what does a software patch promised by April 2019 help? turn off MCAS as well if the autopilot disengages. And I thought these critical software always go through model checking.

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Re: Civil Aviation Development & Discussion

Postby nachiket » 14 Mar 2019 04:37

Even having the system use redundant AoA sensors is not a foolproof solution. The A320 has 3 AoA sensors and their logic is (or atleast was) that if one of the sensor's does not agree with the other two, it is broken and should be ignored. In the XL Airways 888T crash, 2 of the sensors failed due to water ingress while washing the aircraft (which then froze at altitude). The system incorrectly determined that the one sensor which had a different value should be ignored, when in reality it was the only one providing the right value.

Of course the 888T crash occurred due to the crew performing flight tests (it was an airline acceptance flight) at a low and unsafe altitude along with other mistakes like allowing the speed to drop too low during the low-speed flight test. But the failure of the AoA sensors was a contributing cause and having the system rely on 3 different sensors did not help.

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Re: Civil Aviation Development & Discussion

Postby vasu raya » 14 Mar 2019 05:27

With other aircraft safely flying, I don't think that was an unsolved problem. Redundancy is very basic, isn't. MCAS was introduced to solve the stall problem should the pilots become disoriented and not realize it, a learning from the Air France crash flying in bad weather from Brazil. if autopilot is disengaged which somehow figures that the sensors are not working, why would they want MCAS going on?

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Re: Civil Aviation Development & Discussion

Postby arshyam » 14 Mar 2019 06:27

Is autopilot engaged when taking off? Maybe that's a workaround while Boeing fixes the issue - keep autopilot disengaged till reaching 10000 ft or something. Going by reports (and they could be pure speculation for all I know), MCAS seems to get confused between a genuine stall scenario and the pitch up position during take off. After 10000 feet, the aircraft's AoA is not that high as it goes up to cruise altitude, so maybe MCAS does not kick in then.

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Re: Civil Aviation Development & Discussion

Postby arshyam » 14 Mar 2019 06:30

OpIndia has a detailed article about this issue. The author does not draw conclusions, but goes into details of what is AoA, stall, MCAS, etc. A good primer for those who are not familiar with these terms.

Ethiopian Airlines Crash: A close look at Boeing 737 MAX 8 systems - Sambit Nayak, OpIndia

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Re: Civil Aviation Development & Discussion

Postby vasu raya » 14 Mar 2019 07:08

Have a slightly different take from the above article, so far no official version is released,

In the Lion Air crash, the autopilot was disengaged but the MCAS is an independent module (fits in with the new design requiring it regardless of whether autopilot is engaged or not) and pilots were not even aware that its causing the pitch down, the MCAS maybe doing that due to a faulty AoA sensor. The pilots leveled off at low altitude to avoid the uncommanded pitch down movement, still they crashed. Boeing released a statement on how to disable the MCAS (as its not part of the autopilot) and updated the manuals after the incident.

Autopilot is working with multiple sensors so has info to decide if faulty sensor readings are coming in and can disengage while MCAS maybe receiving feed from only one AoA sensor

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Re: Civil Aviation Development & Discussion

Postby Singha » 14 Mar 2019 07:31

from what i read Ethiopia wants the decoding to be done by the UK agency.

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Re: Civil Aviation Development & Discussion

Postby Singha » 14 Mar 2019 08:52

image from NYT that shows the comparable vertical speed graph of ehiopian and lion air flights

https://static01.nyt.com/images/2019/03 ... width=1620

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Re: Civil Aviation Development & Discussion

Postby Austin » 14 Mar 2019 09:13

U.S. Grounds Boeing 737 After Latest Crash Linked to Earlier One

https://www.bloomberg.com/news/articles ... emium-asia

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Re: Civil Aviation Development & Discussion

Postby Austin » 14 Mar 2019 09:15

Singha wrote:image from NYT that shows the comparable vertical speed graph of ehiopian and lion air flights

https://static01.nyt.com/images/2019/03 ... width=1620


Looks like the MCAS issue might go beyond AOA sensors

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Re: Civil Aviation Development & Discussion

Postby chetak » 14 Mar 2019 09:49

Austin wrote:U.S. Grounds Boeing 737 After Latest Crash Linked to Earlier One

https://www.bloomberg.com/news/articles ... emium-asia


Gratuitously lost moral and technical authority by a formerly well reputed organization.

Going forward, many organizations may resort to unilateral decisions in the future, without waiting for the FAA to take a leadership position in crises situations

Undoubtedly, fear of legal ramifications and liability issues have played a very large part in this shameful affair.

The statement below is pure BS, made rather helplessly after many other countries /operators have taken it upon themselves to ground the Max8s and the conspicuous nonaction, both by Boeing and the FAA became untenable.

After several days of little or no hard information -- and delays by Ethiopian authorities in sending the plane’s two black boxes to a lab where the damaged devices could be analyzed -- the FAA had as recently as Tuesday said there was no evidence to justify an action against the Max.

“We were resolute in our position that we would not take action until we had data to support taking action,” Elwell said. “That data coalesced today and we made the call.”

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Re: Civil Aviation Development & Discussion

Postby Singha » 14 Mar 2019 10:57

why would AoA sensors fail in indonesia or ethiopia which are not icy conditions and low height of max 8000feet per logs.
these are supposed to rugged devices capable of years of defect free operation with proper care.

while MCAS will deservedly get the blame for wrong intervention, the tip of the spear is erroneous readings from the 2 aoa sensors.

do aoa sensors fail often on other a/c ? are these aoa sensors some now "value engineered" ones of lesser cost?

do any other airliners have less than 3 aoa sensors ?

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Re: Civil Aviation Development & Discussion

Postby chetak » 14 Mar 2019 11:05

Singha wrote:why would AoA sensors fail in indonesia or ethiopia which are not icy conditions and low height of max 8000feet per logs.
these are supposed to rugged devices capable of years of defect free operation with proper care.

while MCAS will deservedly get the blame for wrong intervention, the tip of the spear is erroneous readings from the 2 aoa sensors.

do aoa sensors fail often on other a/c ? are these aoa sensors some now "value engineered" ones of lesser cost?

do any other airliners have less than 3 aoa sensors ?


One possibility of insect infestations??

some types of insects, especially certain wasps build mud encrusted shelters in crevices of pitot tubes and such like places and maybe the AOA sensors have some sort of crevices where these insects may find it advantageous to seek shelter??

these insects are generally present in warmer climes as opposed to the much more cooler environs of europe or the US.


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