Page 2 of 3

Re: Boeing 737

PostPosted: Wed Mar 13, 2019 5:45 pm
by klonk
grzegorz wrote:Is it just me or do you smell a rat too?

It seems odd that the most countries are calling off flights with the Boeing 737 and the US won't.

I think it's just another blatant example of the coorperate takeover of the US government.

I am not an aviation engineer but doesn't seem like putting all flights of the 737 on hold for a few weeks is asking for much.


The US FAA is a big ponderous bureaucracy that follows its internal rules scrupulously. When they said Monday they didn't have enough evidence to ground the planes, I don't doubt that they meant it. On Wednesday, citing fresh evidence, they issued the grounding directive.

I have my own ideas about the crashes, but not enough info to be sure I know what I am talking about. I do not think a stick pusher is a good idea in the first place, and if it malfunctions you should certainly turn it off, but it's too soon to tell whether that was the scenario or not.

Re: Boeing 737

PostPosted: Wed Mar 13, 2019 6:08 pm
by windwalker
Don't agree with the grounding by the US but understand the rational.
The black box will tell the story.

Regarding training

Flight 235 was the second fatal accident involving a TransAsia Airways ATR aircraft within seven months: Flight 222 had crashed on 23 July 2014, killing 48 of the 58 on board.


Shortly after take-off, a fault in the auto-feather unit of the number 2 engine caused the automatic take-off power control system to auto-feather that engine.[4][a] The flight crew misdiagnosed the problem, and shut down the still-functioning number 1 engine.[4] The aircraft reached an altitude of 1,630 feet (500 m) and then began descending until it crashed.[6][7] The last pilot communication to air traffic control was: "Mayday, mayday, engine flameout."[8][9] At 10:55,[10] the aircraft crashed into the Keelung River, on the border of Nangang District of Taipei and Xizhi District of New Taipei.


Image

It was later found that the pilot did the right procedure but to the wrong engine.


The ASC issued an interim report on 2 July. Without assigning responsibility for the crash, the report confirmed that a still-functional engine number one was incorrectly shut down by the pilot following the failure of engine number two.[1][2] The report also stated that the pilot in command had failed to pass a simulator test in May 2014,


The loss of power from both engines was not detected and corrected by the crew in time and the aircraft stalled during the attempted restart at an altitude from which they could not recover. Ineffective flight crew coordination, communication, and threat and error management compromised the safety of the flight. The crew failed to obtain relevant data from each other regarding the status of both engines. The pilot flying did not appropriately respond to input from the pilot monitoring

https://en.wikipedia.org/wiki/TransAsia ... Flight_235

Re: Boeing 737

PostPosted: Wed Mar 13, 2019 6:35 pm
by windwalker
The FAA and Boeing say the software upgrade that's due in April will give pilots greater control in case problems emerge with the planes' safety systems.
Boeing said the company plans to include an update to the Maneuvering Characteristics Augmentation System (MCAS) flight control law.
"The enhanced flight control law incorporates angle of attack (AOA) inputs, limits stabilizer trim commands in response to an erroneous angle of attack reading, and provides a limit to the stabilizer command in order to retain elevator authority," Boeing said.
The software fix will also include updates to pilot displays, operation manuals and crew training.


The pilots on the Lion Air flight had repeatedly fought to override the MCAS, which pulled the plane's nose down more than two dozen times, according to a preliminary report released in November by Indonesia's National Transportation Safety Committee.
The report said the system was responding to incorrect data transmitted by an AOA sensor, which had proved faulty on earlier flights and had been replaced.
Lion Air's operational director claimed Boeing's operational manual for the Max 8 didn't contain adequate information about the new MCAS system. Boeing Chief Executive Dennis Muilenburg told Fox Business Network at the time that the information was available as part of the training manual.

A week after the Lion Air crash, Boeing warned airlines about how to address erroneous readings related to the plane's external sensors.

https://www.cnn.com/2019/03/13/politics ... index.html

Have worked with engineers who worked for Boeing befor.
The company can be quite arrogant according to them...

In light of the new information the grounding was the only real choice


condolences for the lost souls .

Re: Boeing 737

PostPosted: Wed Mar 13, 2019 7:49 pm
by Steve James
Years ago, there were cases where --for some mechanical reason-- depressing the right rudder pedal (that makes the plane turn right) was actually making the plane veer left. So both pilots continued to push right rudder and dove the plane into the ground.

In this case, the black boxes and voice recorders should determine whether it was computer or pilot input error. Usually, if the computer (or autopilot) is struggling to push the plane nose down, it's because it senses a stall is coming. If this is a computer issue, imho, it has to be more widespread than just this model. It should affect any plane that uses the MCAS.

It's also surprising that this would happen when visibility was clear. It's scary.

Re: Boeing 737

PostPosted: Thu Mar 14, 2019 1:21 am
by grzegorz
Will be interesting to know why Canada and then the US decided to not to fly the 737.

It seems that certain information led them to that decision. I am glad they did because it would be irresponsible to keep flying them if there is a problem just to save Boeing's reputation.

Re: Boeing 737

PostPosted: Thu Mar 14, 2019 11:11 am
by roger hao
They said - because your post -


blatant example of the coorperate takeover of the US government

Re: Boeing 737

PostPosted: Thu Mar 14, 2019 11:41 am
by Steve James
Fwiw, I took a chance and watched this video. It covers several of the issues we've been addressing, but it comes down to a "corporate" decision.


https://www.youtube.com/watch?v=eekdPXOPn8g

Re: Boeing 737

PostPosted: Thu Mar 14, 2019 1:34 pm
by windwalker
It is interesting.
For those interested this clip goes into some detail
explaining what happened and is happening.


https://www.youtube.com/watch?v=XJwUk5HH4KI


explains some of the automation systems


https://www.youtube.com/watch?v=zfQW0upkVus

Re: Boeing 737

PostPosted: Thu Mar 14, 2019 1:47 pm
by Steve James
In the first, video he says clearly (around 7 minutes) that no one knows what happened. He's not explaining the accidents, per se.

The second video is really on point, and problems with aoav sensors have happened before.

Re: Boeing 737

PostPosted: Thu Mar 14, 2019 7:43 pm
by Steve James

https://www.youtube.com/watch?v=6GV0W-rj3VE

They find similarities between the crashes, but the question is really why it hadn't happened more often. I.e., what was the specific situation that caused these two crashes? It doesn't happen all the time.

It seems more and more likely that there'll be some suits. The commercial pilots associations are sure to complain, since they have complained earlier. However, Congress seems set to investigate any possible connection between Boeing and the FAA that allowed the plane to be certified despite known issues.

Re: Boeing 737

PostPosted: Fri Mar 15, 2019 5:18 pm
by klonk
On the evidence that spurred the US to ground the MAX:

https://www.youtube.com/watch?v=AgkmJ1U2M_Q

Re: Boeing 737

PostPosted: Tue Mar 19, 2019 2:56 pm
by grzegorz
The Secretary of Defense is a Boeing Executive.

Explains everything!

Re: Boeing 737

PostPosted: Tue Mar 19, 2019 3:13 pm
by windwalker
grzegorz wrote:The Secretary of Defense is a Boeing Executive.

Explains everything!



Is he still working for Boeing?
What does it explain?

The planes go through a very extensive review process prior
to being certified. That process is now being examined to determine
if there was anything that should have flagged the plane from being certified.

The Seattle Times has the most detailed analysis on this, diving into the certification process and internal affairs at the time. To compete with Airbus, who was nine months ahead with the A320neo family, Boeing and the FAA worked hard to minimize the test and certification process whilst meeting all requirements.

https://samchui.com/2019/03/18/ethiopia ... JFoHihKhnI

Re: Boeing 737

PostPosted: Tue Mar 19, 2019 3:35 pm
by Steve James
I agree about the certification and review process for aircraft. But, fwiw, many people are concerned about Shanahan's position.
https://www.military.com/daily-news/201 ... oeing.html

I wouldn't be surprised if people at Lockheed are also concerned. But, I don't think it's about product safety. It's more about the "military industrial complex" where businessmen (not military personnel) decide on procurement and what should be developed. How do we know they are not promoting their business interests, even sub-consciously. If Boeing gets more contracts now than it did before, eyebrows raise.

Re: Boeing 737

PostPosted: Tue Mar 19, 2019 8:57 pm
by Michael