What was that about AoA again?

Larry in TN said:
They don't troubleshoot and repair based on personal systems knowledge. They follow the procedures in the aircraft maintenance manual. If those manuals were lacking it will come out in the investigation.
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Or the manuals were not current. The airline got dinged multiple times in the past few years for maintenance issues.

Sent from my SM-J737T using Tapatalk
 
MCAS would not be a “thing” there is no computer or box or switch pack, it’s just a software function. Besides that MCAS was probably functioning exactly as it was designed to, the actual hardware problem was probably causing multiple anomalies. Whithout being there it’s hard to say why they fought this twenty times and apparently never flipped the stab cutout switches. I think the CVR would tell a lot and it’s weird that they haven’t found it, they are both mounted to the same rack.
 
https://leehamnews.com/2018/11/14/b...-the-737-max-was-not-disclosed-to-the-pilots/

This is a two week old article explaining why Boeing considered MCAS to be necessary in the 737 MAX models. MCAS is described as a software loop in the flight control computer designed to counter the MAX's lower stability margins at high angles of attack (compared to the 737NG) for reasons explained in the article related to the larger and more forward engine nacelles required for the higher bypass LEAP-1B engines.
 
Stan Cooper said:
This is a two week old article explaining why Boeing considered MCAS to be necessary in the 737 MAX models.
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Many airplanes have pitch stability augmentation like that. Even the 37MAX has trim runaway and/or uncommanded trim abnormal procedures. Were they followed in this case? Were they followed in the flight that preceded this one? Rhetorical, BTW, but they're answered in the prelim report and partially in the data you posted.

Nauga,
who says, "cut it out"
 
I get all of that. What's missing for me is whether the procedures in the AFM are as clear and unambiguous as those published in AD 2018-23-51 after the accident which addresses the problem directly with specific instructions. It would seem from the AD requiring Figures 1 and 2 be pasted into the AFM that the pre-accident procedures may have been lacking.
AD%202018-23-51%20Figs%201%20and%202_zps0syclbzw.jpg
 
Tarheelpilot said:
Sounds like it to me. I don't know anything about this Rhino you are speaking of but I can tell you it is not that uncommon to meet pilots flying complex aircraft that think they understand something when they might as well be talking about where the Christmas elf was that morning when they woke up.
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Not uncommon for pilots who fly any aircraft to do that
 
Just us little guys flying little airplanes, but - the Bellanca Super Viking has a characteristic issue with the gas gauges that was known (known by all the pilots who didn't run out of fuel).
4 tanks. 4 gauges.
But (and a big one) the reading on any given gauge when that tank was not selected was random.
i.e. when that tank was unselected the electric was disconnected from that gauge. At the instant the switch contacts opened there could be an electrical bounce and the tank could (and would) read anything from empty to full. Only the two (usually) selected tanks were correct.
It bit a full load of preachers one night over the mountains when the outboards that showed full on the ground turned out to show empty when selected. Praying did not help.
 
Dr. O said:
Just us little guys flying little airplanes, but - the Bellanca Super Viking has a characteristic issue with the gas gauges that was known (known by all the pilots who didn't run out of fuel).
4 tanks. 4 gauges.
But (and a big one) the reading on any given gauge when that tank was not selected was random.
i.e. when that tank was unselected the electric was disconnected from that gauge. At the instant the switch contacts opened there could be an electrical bounce and the tank could (and would) read anything from empty to full. Only the two (usually) selected tanks were correct.
It bit a full load of preachers one night over the mountains when the outboards that showed full on the ground turned out to show empty when selected. Praying did not help.
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How stupid is that ? I mean, seriously who designed stuff like that ?
 
Larry in TN said:
No bigger than any other runaway stabilizer trim event and it is handled no different
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I'd argue that a stab runaway caused by software is a bigger problem for Boeing than a runaway caused by a one-off mechanical failure. We have two independent sources for AoA data, and therefore the flight computer has the means to determine if the data is generally reliable. I think it's a problem for MCAS to be capable (either by design or by bug) of activating based on only one set of data.

Yes, I know how to handle a stab trim runaway. I also know how to handle a V1 cut. Doesn't mean I have to be happy to discover that an engine will shut down if the EECs lose a friggin' temperature input. Oh, and that the shut down was ordered by some piece of software that nobody seemed to know even existed. ;)
 
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