Boeing 737 MAX - software wouldn't fix faulty airframe

nsaspook

Joined Aug 27, 2009
16,369
A lot more smoke than fire for Boeing. The FAA is in the hot seat.
The FAA said in a statement that its review board "determined the issue to be 'low risk' and would be required to be a part of Boeing's overall enhancement announced after the Lion Air [crash]. However, Boeing's timely or earlier communication with the operators would have helped to reduce or eliminate possible confusion."
 

justtrying

Joined Mar 9, 2011
439
A lot more smoke than fire for Boeing. The FAA is in the hot seat.
FAA can get out of this by pulling the plug on thw plane and forcing recertification. That is the only way for FAA to "restore trust" in their process. What can boeing do except continue their mantra "we have followed the process" and "we are the champions of safety"?

Also, they keep saying that it was a different condition that caused the crash (the AOA sensor and runaway trim), which exist on all other planes. That actually makes it worse in a way for a lay person... Look up AOA sensor failure rate on previous planes and you really have to wonder what went through their head.
 

justtrying

Joined Mar 9, 2011
439
Well, the Russians don't have problems with software but they do have problems with airplanes.
https://www.usatoday.com/story/news...oscow-jet-landing-caught-on-video/1112076001/
https://www.flightradar24.com/data/flights/su1492#20671283

Yes, I'd fly in one, as the last flight outta hot war zone.
You conviniently left out the Boeing that went into the river in Florida just a few days prior. I did not write about it as I dont know what happened.

Now, the plane that crashed in Moscow was struck by lightning.
 

nsaspook

Joined Aug 27, 2009
16,369
I am sorry, i skipped that post. Couldnt handle the satire below. The 300 lives lost dont deserve it...

From 2016, interesting read.

https://www.telegraph.co.uk/travel/...iest-airline-to-one-of-the-safest-in-the-sky/
Those Soviet aircraft have been replaced by Western-built jets. The Tupolev Tu-154 was retired in 2009, and its fleet now consists almost exclusively of Airbus and Boeing aircraft, including 777s and A330s

Looks like the plane that crashed was a Russian built bird so I still not flying one of those.
https://en.wikipedia.org/wiki/Sukhoi_Superjet_100#Accidents_and_incidents
 

justtrying

Joined Mar 9, 2011
439
Those Soviet aircraft have been replaced by Western-built jets. The Tupolev Tu-154 was retired in 2009, and its fleet now consists almost exclusively of Airbus and Boeing aircraft, including 777s and A330s

Looks like the plane that crashed was a Russian built bird so I still not flying one of those.
https://en.wikipedia.org/wiki/Sukhoi_Superjet_100#Accidents_and_incidents
Well, you are safe unless you go to russia, asia or africa...

I only go to states if my work forces me... The World Divided... No need for walls :(
 

nsaspook

Joined Aug 27, 2009
16,369
Well, you are safe unless you go to russia, asia or africa...

I only go to states if my work forces me... The World Divided... No need for walls :(
I tempted fate far too many times riding in the back of USMC helicopters patched up with beer cans. No need to push my luck with Russian aircraft designs.
 

WBahn

Joined Mar 31, 2012
32,974
Working in healthcare, i see these chains of events all the time. Often obvious things are present that no one corrects because they are still following the approved process. That is until a disaster strikes. Question - why does it take a catastrofic failure to overhaul systems? Human nature? Lazyness? Greed?
Priorities more than anything, in most cases.

When you are dealing with complex systems -- and a modern jetliner is an extremely complex system -- you simply don't have the luxury of treating everything like a top priority item. You have to prioritize what you do and when you do it according to the best assessment you can make at the time within the resources and data available. You also don't have the luxury of reassessing every item as new information comes available. Then you work down the list -- a list which probably has thousands of items on it at any given time.

If we refused to fly a plane until all of the bugs were investigated and resolved, the Wright's great-great grandkids would still be trying to get the Flyer finished and they would probably still be the first to get a plane in the air.
 

Glenn Holland

Joined Dec 26, 2014
703
Priorities more than anything, in most cases.

When you are dealing with complex systems -- and a modern jetliner is an extremely complex system -- you simply don't have the luxury of treating everything like a top priority item. You have to prioritize what you do and when you do it according to the best assessment you can make at the time within the resources and data available. You also don't have the luxury of reassessing every item as new information comes available. Then you work down the list -- a list which probably has thousands of items on it at any given time.

If we refused to fly a plane until all of the bugs were investigated and resolved, the Wright's great-great grandkids would still be trying to get the Flyer finished and they would probably still be the first to get a plane in the air.
From my experience with mass transit vehicles and wayside control systems, the debugging is done at the vendor level for each subsystem and the general contractor (the complete vehicle builder) debugs the "integrated" system.

It's an example of the "stochastic" approach where the failure modes for each subsystem are analyzed independently. The checked redundant principle is also used so a single point failure can't propagate to other subsystems and compromise the entire system as a whole. It's an exercise in quality assurance.
 

justtrying

Joined Mar 9, 2011
439
From my experience with mass transit vehicles and wayside control systems, the debugging is done at the vendor level for each subsystem and the general contractor (the complete vehicle builder) debugs the "integrated" system.

It's an example of the "stochastic" approach where the failure modes for each subsystem are analyzed independently. The checked redundant principle is also used so a single point failure can't propagate to other subsystems and compromise the entire system as a whole. It's an exercise in quality assurance.
Note the statements coming from Boeing about the fact that fault was never with MCAS, but with runaway trim (as was reiterated many times by NSAspook). Boeing also keeps saying that in this case all you need to do is shut the MCAS off and fly the plane without it. So then why is the software on the plane in the first place? If it is apparently not necessary for safe flying? To confuse the pilots?
 

nsaspook

Joined Aug 27, 2009
16,369
Note the statements coming from Boeing about the fact that fault was never with MCAS, but with runaway trim (as was reiterated many times by NSAspook). Boeing also keeps saying that in this case all you need to do is shut the MCAS off and fly the plane without it. So then why is the software on the plane in the first place? If it is apparently not necessary for safe flying? To confuse the pilots?
The 737 Max without MCAS meets the requirements: https://www.ecfr.gov/cgi-bin/text-idx?node=14:1.0.1.3.11#se14.1.25_1173


Review this video please at about 11:45. They did it to sell planes just like airbus does with type certification and pilot type rating.
https://forum.allaboutcircuits.com/...x-faulty-airframe.158329/page-10#post-1389259

Is it really that hard to understand why?
 
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justtrying

Joined Mar 9, 2011
439
The 737 Max without MCAS meets the requirements: https://www.ecfr.gov/cgi-bin/text-idx?node=14:1.0.1.3.11#se14.1.25_1173


Review this video please at about 11:45. They did it to sell planes just like airbus does with type certification.
https://forum.allaboutcircuits.com/...x-faulty-airframe.158329/page-10#post-1389259

Is it really that hard to understand why?
They created a plane that tends to pitch more than those of previous generations and added software to automatically correct for the pitch problem. Software was hidden and fed by one sensor. The AOA sensors were preexisting.

Aerobus planes are far more automated at this point from what I read with pilots having to do very little. So, if this was Boeings attempt to introduce some more automation without recertificatio , they clearly failed. Champions of safety as they are.
 

nsaspook

Joined Aug 27, 2009
16,369
They created a plane that tends to pitch more than those of previous generations and added software to automatically correct for the pitch problem. Software was hidden and fed by one sensor. The AOA sensors were preexisting.

Aerobus planes are far more automated at this point from what I read with pilots having to do very little. So, if this was Boeings attempt to introduce some more automation without recertificatio , they clearly failed. Champions of safety as they are.
Yes, they failed in implementing what should have been a safe and effective solution to type certification. For this failure they should and are being held accountable. I just don't like to see personal fantasies and biases being substituted for easy to verify facts.
Boeing still lets the pilot fly the plane with computer assist. For someone who has railed about software deficiencies this would seem to be better than airbus where the computer only takes suggestions from the pilots on how to fly the plane.
 

justtrying

Joined Mar 9, 2011
439
Yes, they failed in implementing what should have been a safe and effective solution to type certification. For this failure they should and are being held accountable. I just don't like to see personal fantasies and biases being substituted for easy to verify facts.
Boeing still lets the pilot fly the plane with computer assist. For someone who has railed about software deficiencies this would seem to be better than airbus where the computer only takes suggestions from the pilots on how to fly the plane.
I am not a pilot, neither am I an aviation expert. I only started to look at what Aerobus does in their design out of curiosity. I do know a lot avout software deficiencies and how difficult it is to fix them in my field of expertise.
 

Glenn Holland

Joined Dec 26, 2014
703
If Boeing can't come up with a fix that gets the 737 Max back in the air, the airlines will sue the company for "breach or merchantability" and orders for future deliveries will be canceled. Then it's a sure bet that Boeing will file for bankruptcy (or most likely reorganization) to get all the creditors off its back. What ever the strategy, the company has got one big dark cloud over it's head.
 
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