B737 Max : CAA bans from UK airspace; Comair aircraft grounded
Mar 12, 2019, 8:04 pm
#166
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Ethiopian doesn't have an unblemished reputation. But that's not the point, an airliner should be flyable by the worst case qualified pilot. If this is MCAS on both accidents - not established yet - Then evidently that bar was not reached.
Plenty of commentators lamenting excess of automation, but this really isn't a case of that. It appears to be an ill-thought through software fix to a 60 year old design (they grafted on more efficient engines, thereby radically changing the CoG, and the system cuts in only during manual flight. Autopilot would be OK.
Plenty of commentators lamenting excess of automation, but this really isn't a case of that. It appears to be an ill-thought through software fix to a 60 year old design (they grafted on more efficient engines, thereby radically changing the CoG, and the system cuts in only during manual flight. Autopilot would be OK.
Mar 13, 2019, 4:52 am
#167
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Mar 13, 2019, 5:38 am
#168
Join Date: Feb 2011
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A spokesman for Boeing confirmed the conversation and said [Boeing CEO] Muilenburg "made clear to the president that the MAX aircraft is safe."
Quite disturbing really.
Mar 13, 2019, 6:26 am
#169
Join Date: Aug 2011
Location: Hong Kong
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Oh, hang on...
Umm....
Mar 13, 2019, 8:30 am
#171
Join Date: Oct 2018
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Software update is only part of the issue.
737Max has left and right Angle of attack sensors (I have read that A320 has three AOA sensors). If one gives and erroneous reading, the MCAS defaults to it where with A320, with one erroneous reading it checks with the other two and goes with the two that agree. By the way two sensors is inherently STUPID! How do you know which one is giving the "erroneous" reading? This is clearly a design flaw leading to a single point failure mode with MCAS software.
To completely solve the issue (erroneous AOA input), Boeing needs to go to three AOA sensors and modify the software to demand elimination of the outlier seniors input.
737Max has left and right Angle of attack sensors (I have read that A320 has three AOA sensors). If one gives and erroneous reading, the MCAS defaults to it where with A320, with one erroneous reading it checks with the other two and goes with the two that agree. By the way two sensors is inherently STUPID! How do you know which one is giving the "erroneous" reading? This is clearly a design flaw leading to a single point failure mode with MCAS software.
To completely solve the issue (erroneous AOA input), Boeing needs to go to three AOA sensors and modify the software to demand elimination of the outlier seniors input.
Mar 13, 2019, 8:34 am
#172
Join Date: Apr 2005
Location: Windsor
Programs: BAEC Gold
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Software update is only part of the issue.
737Max has left and right Angle of attack sensors (I have read that A320 has three AOA sensors). If one gives and erroneous reading, the MCAS defaults to it where with A320, with one erroneous reading it checks with the other two and goes with the two that agree. By the way two sensors is inherently STUPID! How do you know which one is giving the "erroneous" reading? This is clearly a design flaw leading to a single point failure mode with MCAS software.
To completely solve the issue (erroneous AOA input), Boeing needs to go to three AOA sensors and modify the software to demand elimination of the outlier seniors input.
737Max has left and right Angle of attack sensors (I have read that A320 has three AOA sensors). If one gives and erroneous reading, the MCAS defaults to it where with A320, with one erroneous reading it checks with the other two and goes with the two that agree. By the way two sensors is inherently STUPID! How do you know which one is giving the "erroneous" reading? This is clearly a design flaw leading to a single point failure mode with MCAS software.
To completely solve the issue (erroneous AOA input), Boeing needs to go to three AOA sensors and modify the software to demand elimination of the outlier seniors input.
Mar 13, 2019, 8:42 am
#173
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737Max has left and right Angle of attack sensors (I have read that A320 has three AOA sensors). If one gives and erroneous reading, the MCAS defaults to it where with A320, with one erroneous reading it checks with the other two and goes with the two that agree. By the way two sensors is inherently STUPID! How do you know which one is giving the "erroneous" reading? This is clearly a design flaw leading to a single point failure mode with MCAS software.
To completely solve the issue (erroneous AOA input), Boeing needs to go to three AOA sensors and modify the software to demand elimination of the outlier seniors input.
To completely solve the issue (erroneous AOA input), Boeing needs to go to three AOA sensors and modify the software to demand elimination of the outlier seniors input.
Mar 13, 2019, 8:56 am
#174
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What makes me uncomfortable is the issue that made MCAS necessary in the first place (i.e. CofG issue). That element makes me uncomfortable regardless of the outcome of this investigation.
Mar 13, 2019, 9:34 am
#175
Join Date: Jun 2016
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Correct me if I am wrong, but isn’t the reason MCAS is there in the first place is to get the Max to handle the same as the previous generation 737. In doing this, they can achieve a single type rating for pilots. Whilst it may inconvenience the airlines, and impact sales, wouldn’t the safest outcome be to ditch the MCAS and have two type ratings?
Mar 13, 2019, 9:56 am
#176
Join Date: Feb 2011
Posts: 5,797
Correct me if I am wrong, but isn’t the reason MCAS is there in the first place is to get the Max to handle the same as the previous generation 737. In doing this, they can achieve a single type rating for pilots. Whilst it may inconvenience the airlines, and impact sales, wouldn’t the safest outcome be to ditch the MCAS and have two type ratings?
I'm also not sure if the MCAS software is there just to make it handle like the old one, or if it's actually unstable without it.
Mar 13, 2019, 9:59 am
#177
Join Date: Jun 2015
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Correct me if I’m wrong but as I understand it MCAS is there to correct the aircraft from titling and therefore possibly stalling due to the engines. The engines are much bigger and placed further forward than previous design (smaller engines) and at full thrust the nose can drop so the MCAS steps in to prevent this through the stabilisers also(?).
Separately, as with most large corporate the constant obsession with saving costs, driving profit and shareholder value with sometimes the disregard of customer experience, as we’ve seen with BA in recent years, doesn’t always bode well in the end.
Separately, as with most large corporate the constant obsession with saving costs, driving profit and shareholder value with sometimes the disregard of customer experience, as we’ve seen with BA in recent years, doesn’t always bode well in the end.
Mar 13, 2019, 12:45 pm
#180
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It seems the US have finally caught up...
https://www.bbc.co.uk/news/business-47562727
BBC reporting that Trump has announced that the FAA are grounding the 73M...
https://www.bbc.co.uk/news/business-47562727
BBC reporting that Trump has announced that the FAA are grounding the 73M...
US President Donald Trump has said the US Federal Aviation Administration will ground the Boeing 737 Max 8 - the aircraft in Sunday's crash in Ethiopia.
The FAA had previously held out while many countries banned the Max 8 from flying over their airspace.
All 157 people on board the Ethiopian Airlines flight were killed when it crashed just minutes after take-off.
It was the second fatal Max 8 disaster in six months, after one crashed over Indonesia in October, killing 189.
The FAA had previously held out while many countries banned the Max 8 from flying over their airspace.
All 157 people on board the Ethiopian Airlines flight were killed when it crashed just minutes after take-off.
It was the second fatal Max 8 disaster in six months, after one crashed over Indonesia in October, killing 189.