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Boeing To Make Key Change in 737 MAX Cockpit Software (wsj.com)
Boeing is making an extensive change to the flight-control system in the 737 MAX aircraft implicated in October's Lion Air crash in Indonesia, going beyond what many industry officials familiar with the discussions had anticipated. From a report: The change was in the works before a second plane of the same make crashed in Africa last weekend -- and comes as world-wide unease about the 737 MAX's safety grows. The change would mark a major shift from how Boeing originally designed a stall-prevention feature in the aircraft, which were first delivered to airlines in 2017. U.S. aviation regulators are expected to mandate the change by the end of April.
Boeing publicly released details about the planned 737 MAX software update late Monday [Editor's note: the link may be paywalled; alternative source]. A company spokesman confirmed the update would use multiple sensors, or data feeds, in MAX's stall-prevention system -- instead of the current reliance on a single sensor. The change was prompted by preliminary results from the Indonesian crash investigation indicating that erroneous data from a single sensor, which measures the angle of the plane's nose, caused the stall-prevention system to misfire. Then, a series of events put the aircraft into a dangerous dive.
Boeing publicly released details about the planned 737 MAX software update late Monday [Editor's note: the link may be paywalled; alternative source]. A company spokesman confirmed the update would use multiple sensors, or data feeds, in MAX's stall-prevention system -- instead of the current reliance on a single sensor. The change was prompted by preliminary results from the Indonesian crash investigation indicating that erroneous data from a single sensor, which measures the angle of the plane's nose, caused the stall-prevention system to misfire. Then, a series of events put the aircraft into a dangerous dive.
Why the hell wasn't this the case before?
Aren't flight control systems supposed to be triple-redundant anyway? Everything I've read about them says they are; three systems and if there is incorrect data it uses the two that agree.
if ( goingToCrash ) {
dontCrash();
}
You think that's bad, how about the aircraft brought down by a burned out light bulb?
https://en.wikipedia.org/wiki/...
Flying is routine until it isn't. Planes are essentially balancing in the air. It doesn't take much to make one stop flying, and one momentary loss of attention at the wrong time or improper control input can end very badly. All of this x10 if the Pilots haven't been informed of or trained on the failure scenario they're encountering.
-=Lothsahn=-
That would have been prevented by the current system.
It's funny how they point to aviation as nearly infallible when they talk about self-driving cars.
Well, it's a little less than one failure in four million flight hours, that's a pretty amazing safety record. If Tesla self-driving was one failure in four million driving hours, I'd call that very near infallible, compared to human drivers, anyway.
But when they do fail, it's spectacular, and makes news.
Source: http://planecrashinfo.com/caus...
http://www.geoffreylandis.com
It's funny how they point to aviation as nearly infallible when they talk about self-driving cars.
Self-driving cars don't have to be infallible. They just have to be safer than the average person, which is a really low bar.
million dollar aircraft brought down by a cheap sensor failure
Well that's better than the aircraft accident I helped to investigate... The pilot died because of a power switch position he specifically set in order to turn off the system that prevented his aircraft from departing it's "flying" envelope by applying back pressure to his control inputs. When he went to "break" during some ACM training looking over his shoulder at his opponent, he applied too much rudder input, the aircraft snap rolled as it stopped flying and started to tumble, his head was caught between the ejection seat and the canopy and he died of a broken neck before his aircraft hit the water.
That guy died because he wanted the competitive edge and specifically tried to cheat by putting the aircraft in a forbidden configuration....
I'd rather die from a sensor failure than by some stupid mistake I made to get an unfair advantge because I want to win some competition..
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
Let us know when one gets there. All current claims are thoroughly debunked.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
There is an option to disable the system. It's a new system and there was not a lot of training about it though.
Since the alternative source link in the summary appears to link to an article about stock prices, here's some alternative alternative links that actually contain more relevant information:
- Boeing press release
- Gizmodo
- Washington Post
Okay lets suppose that some or all of the stall sensors are malfunctioning. There's another sensor that the computer can look at and that's the altitude. If the ALTITUDE is rapidly falling of course the plane might think, see I was right about this stall! But there's one more thing. Namely if the pilots pulled the stick back and the altitude stops falling the plane should now have enough information to figure out that pushing the stick forward is not the right thing to do.
So it seems like the plane should be able to figure out that it's sensors can't be right even if it doesn't know what's exaxtly wrong.
That is, it's job is to overide the pilots if it's convinced they are ignoring a serious problem or doing something to make it worse. But if they do take action and it improves the situation then the logic should be, trust the pilot. Not, continue assuming the pilot is doing the wrong thing.
Some drink at the fountain of knowledge. Others just gargle.
The pilot has always been able to turn off the system.
Except up until recently 737MAX pilots didn't even know "the system" (MCAS) existed, which IMO is Boeing's biggest mistake in this matter.
They knew it existed but thought it had its old name. The same two switches turn both off.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
A description of alternate law as it applies to aviation can be found here although this focuses on Airbus.
Why is there an "insightful" mod and why isn't it "-1"? If I wanted insight, I wouldn't be reading
Back in your day, plane crashes were a regular occurrence, even though there were far fewer aircraft flying.
Something struck me regarding latitudes: the Air Lion crash was 6 degrees South (Djakarta), the Ethiopian crash was 9 degrees North (Addis Ababa) ; both flights were close to the Equator (symmetrically). Could have something to do with sensors reliability.
Slashdot, fix the reply notifications... You won't get away with it...
It does, but as soon as they let go, the MCAS kicks in again, because it's still active, so if the pilot doesn't catch what's going on, they wind up fighting the aircraft all the way into the ground.
...si hoc legere nimium eruditionis habes...
It's a button in the aft toilet under a locked flap with "beware of the leopard" written on it.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."