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U.S grounds ALL 737 Max

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U.S grounds ALL 737 Max

Old 18th Mar 2019, 14:43
  #81 (permalink)  
 
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Originally Posted by infrequentflyer789 View Post
That is my understanding too, I am just starting to think that I have reached that understanding by just assuming MCAS works the way the rest of the 737 FCC stuff does and not from actual released information.

MCAS clearly used same AOA source on consecutive LionAir flights, the reason for that has not yet been confirmed.
If one segment used AoA1/FCC1, the arcraft landed, power to the FCC was cycled, then upon power up the AoA1/FCC1 would be active, as this FCC is always the active one after a power cycling regarding computing MCAS.
So one sees that there is a 50 percent chance that two consecutive flights will use the same FCC/AoA if the power to the FCC was cycled when on the ground.
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Old 18th Mar 2019, 20:14
  #82 (permalink)  
 
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Originally Posted by SteinarN View Post
If one segment used AoA1/FCC1, the arcraft landed, power to the FCC was cycled, then upon power up the AoA1/FCC1 would be active, as this FCC is always the active one after a power cycling regarding computing MCAS.
So one sees that there is a 50 percent chance that two consecutive flights will use the same FCC/AoA if the power to the FCC was cycled when on the ground.
I fully concur. A further observation is that if power is cycled after every flight, then AoA1/FCC1 would be selected for MCAS and STS every flight.
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Old 18th Mar 2019, 22:55
  #83 (permalink)  
 
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Originally Posted by SteinarN View Post
If one segment used AoA1/FCC1, the arcraft landed, power to the FCC was cycled, then upon power up the AoA1/FCC1 would be active, as this FCC is always the active one after a power cycling regarding computing MCAS.
So one sees that there is a 50 percent chance that two consecutive flights will use the same FCC/AoA if the power to the FCC was cycled when on the ground.
SLF.
Two questions:
1: How often is FCC power cycled?
2: If it is important to alternate AoA/FCC, why is this alternation interrupted by power cycling?

It seems to me, if power cycling can interrupt the alternation of sources/computers, then the alternation is not important at all.
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Old 19th Mar 2019, 01:28
  #84 (permalink)  
 
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would a certain European plane maker be lobbying for the 737 Max to be re-certified in Europe?
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Old 19th Mar 2019, 02:29
  #85 (permalink)  
 
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Does the convening of a grand jury in D.C. and the broad supoena issued by a federal criminal prosecutor to obtain Boeing corporate communications potentially slow down the safety process of finding out what happened and the best way to fix the issues? It cannot be helpful, IMO.

While Boeing and the FAA may eventually be found to have been negligent, the threat of criminal negligence cannot be helpful in the accident investigation process.
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Old 19th Mar 2019, 12:51
  #86 (permalink)  
 
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For as long as the 737 MAX are grounded, and assuming other models are not affected by the same issue, the slowing down of the safety process actually seems more helpful than not, especially if the planes would otherwise be sent up soon with another quick software hack.
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Old 19th Mar 2019, 13:43
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Originally Posted by cooperplace View Post
would a certain European plane maker be lobbying for the 737 Max to be re-certified in Europe?
With the current trade issues being perused across the globe, it could be more than Europe that requires recertification. With Huawei in the crosshairs, I would expect China to be playing a hard line on recertification
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Old 19th Mar 2019, 15:18
  #88 (permalink)  
 
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Originally Posted by Euclideanplane View Post
For as long as the 737 MAX are grounded, and assuming other models are not affected by the same issue, the slowing down of the safety process actually seems more helpful than not, especially if the planes would otherwise be sent up soon with another quick software hack.
Normally, I think, the grounding reduces immediate risk, but the pressure to approve a fix and get the airplanes flying is stronger than ever. Not sure, but I feel encouraged that the third party scrutiny by DOJ and DoT investigations might make things a bit more transparent. We’ll see.

Considering how blame tends to be assigned, I wouldn’t want to be an FAA or Boeing certification engineer right now. When the delegation and oversight processes are scrutinized, management (current and retired) will skillfully deflect responsibility.
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Old 19th Mar 2019, 15:48
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Originally Posted by GlobalNav View Post


Normally, I think, the grounding reduces immediate risk, but the pressure to approve a fix and get the airplanes flying is stronger than ever. Not sure, but I feel encouraged that the third party scrutiny by DOJ and DoT investigations might make things a bit more transparent. We’ll see.

Considering how blame tends to be assigned, I wouldn’t want to be an FAA or Boeing certification engineer right now. When the delegation and oversight processes are scrutinized, management (current and retired) will skillfully deflect responsibility.
The aviation world might be better served in terms of transparency if the involved players were not under threat of criminal prosecution which will cause them to lawyer up more than they already have, allow them to clam up for fear of self-incrimination, and overall delay discovery that would enable a safer future. There may well have been profound negligence on the part of BA and the FAA, but short of a smoking gun email, I would doubt criminal intent.

Three hundred counts of manslaughter, conspiracy to commit murder, ....do we really want to go there?
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Old 19th Mar 2019, 15:52
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Originally Posted by Lake1952 View Post
The aviation world might be better served in terms of transparency if the involved players were not under threat of criminal prosecution which will cause them to lawyer up more than they already have, allow them to clam up for fear of self-incrimination, and overall delay discovery that would enable a safer future. There may well have been profound negligence on the part of BA and the FAA, but short of a smoking gun email, I would doubt criminal intent.

Three hundred counts of manslaughter, conspiracy to commit murder, ....do we really want to go there?
I think it would be VERY strange if this option were taken away in a circumstance which, superficially at the very least, bears the traits of corporate manslaughter.
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Old 19th Mar 2019, 15:59
  #91 (permalink)  
 
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Originally Posted by cooperplace View Post
would a certain European plane maker be lobbying for the 737 Max to be re-certified in Europe?
https://www.forbes.com/sites/marisag.../#a6a5fcd74f4d

Interesting article about the topic
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Old 22nd Mar 2019, 06:41
  #92 (permalink)  
 
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One reads/hears the mantra “Safety is our no. 1 concern”. from airlines and aircraft manufacturers so it is with some head scratching as to why why the AoA disagree light is just an option.
I treat this mantra with a touch of disbelief.



Originally Posted by FCeng84 View Post


This gets into the whole topic of presenting the crew with data they need to do their job but no more that might be distracting. I’m in the camp that AOA is a key to flight and should be displayed. There are other opinions.
I read that Boeing say they will now provide these items free of charge. Shameful they weren’t included as a basic safety feature Boeing say is their number 1 concern. I think my cynicism on that mantra used by anyone is justified.
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Old 22nd Mar 2019, 07:20
  #93 (permalink)  
 
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Originally Posted by Gove N.T. View Post
One reads/hears the mantra “Safety is our no. 1 concern”. from airlines and aircraft manufacturers so it is with some head scratching as to why why the AoA disagree light is just an option.
I treat this mantra with a touch of disbelief.





I read that Boeing say they will now provide these items free of charge. Shameful they weren’t included as a basic safety feature Boeing say is their number 1 concern. I think my cynicism on that mantra used by anyone is justified.
It would be interesting to know the history of these options. I would imagine that this story looks something like one of the two following flavors;

1. Did Boeing originally offered these options with some customers choosing them and others declining?

2. Or did Boeing design the 737MAX flight deck without them only to have some customers request them to which Boeing agreed provided those to customers who were willing to pay enough to cover the development costs?

In all the talk about airlines having to pay extra for these AOA displays and AOA disagree message I have not heard how much they cost. Without understanding the full history (which I don't) it seems unfair after seeing these displays only on some 737MAXs to jump to the conclusion that Boeing was using them as a way to get more out of customers willing to pay for them.
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Old 22nd Mar 2019, 07:55
  #94 (permalink)  
 
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Originally Posted by FCeng84 View Post
It would be interesting to know the history of these options. I would imagine that this story looks something like one of the two following flavors;

1. Did Boeing originally offered these options with some customers choosing them and others declining?

2. Or did Boeing design the 737MAX flight deck without them only to have some customers request them to which Boeing agreed provided those to customers who were willing to pay enough to cover the development costs?

In all the talk about airlines having to pay extra for these AOA displays and AOA disagree message I have not heard how much they cost. Without understanding the full history (which I don't) it seems unfair after seeing these displays only on some 737MAXs to jump to the conclusion that Boeing was using them as a way to get more out of customers willing to pay for them.
I did read somewhere, dont remeber where, that the price asked by Boeing was 60,000 US$ for the AoA indicator/display. I dont know if that could be correct, if it is, then it is not cheap at all.
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Old 22nd Mar 2019, 08:11
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Originally Posted by SteinarN View Post
I did read somewhere, dont remeber where, that the price asked by Boeing was 60,000 US$ for the AoA indicator/display. I dont know if that could be correct, if it is, then it is not cheap at all.
How many orders do you have to spread the development costs across? $60K doesn’t seem that high if the non-recurring costa are spread over 30 to 50 planes
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Old 22nd Mar 2019, 08:25
  #96 (permalink)  
 
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Originally Posted by FCeng84 View Post


How many orders do you have to spread the development costs across? $60K doesn’t seem that high if the non-recurring costa are spread over 30 to 50 planes
That is true.
But first you have to decide how many aircraft you can sell with this option. Say you think you only can sell one aircraft. Then you must charge say 1 million for that option. Ofc you wont get any sales at that asking price.
Let say you think you can sell 50 airplanes, than the 1 million non-recurring is down to $20K per aircraft. How many will you now sell, might be hard to tell, you think you will get some sales.
What if you think you can sell 6,000 aircraft with that option? Then the non-recurring cost would be only $166 for each aircraft. I think everyone would take that option for such a low cost and you would sell it on the full production run of the aircraft family. You could just as well make it standard.
I suppose the actual recurring cost for this option would be close to zero, isnt that correct?
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Old 22nd Mar 2019, 08:34
  #97 (permalink)  
 
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While the cost you use and the logic you use may be correct, (or not), I would hazard a guess and say you aren't an airline beancounter............ "Cost of everything, value of nothing", as the saying goes.
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Old 22nd Mar 2019, 08:34
  #98 (permalink)  
 
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AoA

FCeng #95
Reading between the lines and industry articles, the demand appears to originate from misguided ‘solutions’ for LoC recovery (little consideration of how the situation should have been avoided in the first instance).
Also, perhaps more influential, proposals from eminent safety gurus, Unions, and individual Airlines.
Unfortunately this appears to be the current state of industry knowledge, or the perception of aspects which might previously be taken as known; less so today.

Boeing 737 Max Software Fixes Due to Lion Air Crash Delayed
https://theaircurrent.com/aviation-s...737-max-fleet/
https://thepointsguy.com/news/southw...ion-air-crash/

Related, and relevant:-
A US author, for US audience, about US education; however, if the aspects of IT / web and their effect on thinking - social change, then the world-wide aviation industry might face a greater threat than one errant system design.
https://www.foreignaffairs.com/artic...aith-expertise





Last edited by PEI_3721; 22nd Mar 2019 at 08:45. Reason: Link Software fixes
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Old 25th Mar 2019, 12:19
  #99 (permalink)  
 
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Originally Posted by Big Pistons Forever View Post
I find conspiracy theories about the MAX pretty hard to believe. What is easy to believe is a Boeing management engineering culture that prioritized the absolute minimum changes to the 737 so that Boeing could advertise upgrading to the Max would not incur any training cost to airlines.
That's a crowbar separation. If you mean that Boeing did NOT have a meeting on a basement floor where Muilenberg said, "Let's put passengers in grieve danger to line our pockets with gold", no, that probably never happened... I hope. So the differential you pose is strictly linguistic. It wasn't a "conspiracy" but I seriously doubt nobody questioned the new system and its implementation. One of the whistleblowers is suing Boeing and Boeing's defence of "he was a bad enginner because he expenced alcoholic beverages on business dinners" is not indicative of a strong "discussion culture" in the company.
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