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Chinese Carriers, Ethiopian Airlines Halt Use of Boeing 737 MAX 8 Aircraft After Crash (reuters.com)
China's aviation regulator today grounded nearly 100 Boeing Co 737 MAX 8 aircraft operated by its airlines, more than a quarter of the global fleet of the jets, after a deadly crash of one of the planes in Ethiopia. From a report: However, a U.S. official said it was unclear what information the Chinese regulator was acting on because the investigation of Sunday's crash, the second involving the latest version of the narrowbody jet, was in the early stages. Speaking on condition of anonymity as the topic is sensitive, the U.S. official said there were no plans to follow suit, as the jet had a stellar safety record in the United States and there was a lack of information on what caused the Ethiopian crash.
I'm going out in a limb here but maybe they were acting on the information that another one had crashed.
Without any accident investigation (and they are usually though) an analysys two crashes in six months are just a coincidence.
Your speculations are worthless.
Normally, I'm pretty happy to fly on any well maintained airplane, but a second crash within 5 months, where the early indications are that the plane crashed itself despite the best efforts of the pilots to prevent that, would make me cautious of flying on a 737 MAX 8.
How does that quote go: "To lose one parent may be regarded as a misfortune; to lose both looks like carelessness."
Unless Boeing get this sorted out very fast then folks will reinterpret "MAX 8" to be the maximum amount of time in minutes that the plane will stay in the air ...
when last I checked, a "lack of information" is a great reason to avoid something dangerous. Actually, it might be the one and only and best reason to avoid anything dangerous -- from bicycles to bungee jumping. Get informed first. And if you thought you were informed, and suddenly you discover that you aren't informed because you can't explain something that happened, well then, avoid again until you become informed again.
In other words, let someone else run the tests. That's exactly what test-pilots are for.
Ethiopia is predominantly Christian.
Except we do have information. One has gone through accident investigation that hasn't been published yet, but has been completed and was serious enough that 2 advisories have been issued. It would appear as though there actually is a problem in these aircraft. Both crashed during takeoff. Both had problems with vertical ascension. One had a specific advisory on instruments used during ascending.
You're right it'll remain somewhat speculative until both incidents have gone through a complete review, but there are already indications pointing to systemic issues rather than just pure coincidence.
The ground search (well, digging into the ground) has located both FDR (Flight Data Recorder) and CVR (Cockpit Voice Recorder) for the crashed aircraft, which should help greatly in determining what the problem was/ is.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
YouTube: Mentour Pilot
The last ten years we had like 4 or 5 airplane crashes.
Now we have 2 in a row just during a 5 month period, same type of _new_ airplane. Most likely not a coincident but a systematic fault in the plane.
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
To be fair: All crash landings* involve problems with vertical ascension, and takeoff is by far the riskiest portion of the flight. The lack of altitude results in little time to recover from any issue. Thus, it is unsurprising to see two accidents on takeoff in a row, often with completely different causes.
* - It is possible to crash a plane on the ground. However, those crashes aren't usually described as crash landings. It's also possible to land a plane and go off the end or side of a runway, etc.
Of course it may be a coincidence. But it is an extremely low probability coincidence.
Let's be clear. The 737-NG and A320 family both have total fatal hull loss rates of less than 1 in 10,000 aircraft years in operation. This is generous and includes all accidents: terrorists, captain suicide, mechanical issue, and pilot error.
The DC-10 - recognized as having a fatal design flaw with its cargo door and widely recognized as a "dangerous" airliner at the time - took 1,600 aircraft flight years before suffering two fatal accidents.
The 737 MAX 8 has had 2 hull losses in less than 300 flight years of operation. That is nearly 70 times higher than the 737-NG and A320 family.
The likelihood of the 737 MAX having the same ultimate failure probability as the 737NG and A320 and having two fatal hull loss accidents in only 300 flight years is something on the order of 1 in a 1000.
Even if the ET302 flight is boiled down to "pilot error" (like the Lion Air flight), that is just an excuse. If the ET302 had the same failure mode as the Lion Air flight, then the fact that you have two separate incidents with a loss of control (shortly after takeoff, meaning less room for root cause analysis, checklists, etc) is a design flaw. Full stop. Whether or not a pilot could recover is not relevant; an airframe should not be constantly testing pilots with unexpected loss of control.
It is still "safe" to fly a 737 MAX 8 relative to most other daily activities. You probably won't die if you fly on one. That said, relative to aviation standards and safety records that we have achieved in the past 50 years, the 737 MAX 8 - today, at least - appears like a veritable statistical death trap.
The Chinese response is the most appropriate, especially since they are not blinded by the fear of damaging profit margins for Boeing. The fact that at least 2 incidents with "unknown" cause involve the same aircraft means its continued use while the cause is unknown is a risk. China recognizes it as an avoidable risk, which it is in reality.
Could be muslim terrorists. Both crashed from heavily predominant Muslim countries.
Time for a Goodwin's Law 2.0: "As an online discussion grows longer, the probability of somebody blaming Islamic terrorists or Muslims in general approaches 1."
If I recall, the previous crash has been linked to a bad angle of attack sensor. This sensor is only used by a new stall protection feature in the 737 Max. When it fails, the stall protection algorithm thinks the plane is stuck in a nose up orientation, and tries to force the nose down... into the ground.
There are several things that should happen:
1. Interim corrective action. Disable stall protection on all 737 Max aircraft.
2. Quality control investigation into the angle of attack sensor reliability.
3. Implement diagnostic algorithms into the control strategy to detect failed angle of attack sensors automatically. A failed sensor should disable the stall protection feature automatically, and alert the pilot.
One of our competitors trademarked the term "hypothesis". From now on, we will call them "boneheaded ideas".
If it was a new Chinese plane the US would ground all of them until we knew the reason. Yes, we do not know the reason so it is sensible to ground them until we do know rather than let people keep dying.
I love stacking my barbecues in the shed at the end of summer - you can't beat a bit of grill on grill action.
Computers should never have the last say in flying an airliner.
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
This is really bad for Boeing.
Well, in the short term, sure. But the issue here just doesn't seem to be a huge problem to me.
Speculation here is that the new stall prevention system on the aircraft is likely the issue. This new system does some unexpected things when there is a sensor failure and if the pilots don't know about the system and how to override it, they can lose control of the aircraft's pitch. Boeing's issue was in not providing proper documentation of this system for the pilots until late last year, AFTER the Indonesian crash. In the Indonesian incident there where indications of the problem in the aircraft's maintenance logs. Where the system was doing strange things, the pilots where complaining about it but maintenance wasn't actually fixing the problem. So there may be a maintenance training and fault tree documentation issue too.
What this is likely to end up being is a pilot and maintenance manual training issue and possibly a design change based on human factors. If this speculation is true, Boeing may be financially liable for the two accidents, but the aircraft is indeed safe to operate, once the pilots and maintenance crews are properly trained.
IF the speculation is right, Boeing isn't in grave danger. The 737 MAX may find a different name and come without the new system, but Boeing's insurers will pay out, Boeing will pay higher rates in the future, but not much else will change.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
Not so fast there AC..
The speculation is that this is a human factors problem too, where some automated system is messing with the pitch controls in weird ways when presented with sensor failures. Where you can mitigate this problem with pilot training (Hey, when this happens, turn of the stall prevention system) there may also be a pilot manual omission issue too. If that's true, the pilots are properly trained per the documentation provided, so the base cause is really the pilot manual omits some important information, so they didn't have a chance to get trained.
So, I'd not be so fast to blame the pilots, or their training. It could be that it's not their fault.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
Regardless how good or bad this particular model may be, one has to remember that neither of the companies involved in the recent crashes is a paradigm to follow when it comes to aircraft maintenance.
Ethiopian's MRO is FAA and EASA certified for B757, B767, B777; FAA only for 737, 787, Q400 and MD11, and EASA only for 73NG, and is Boeing and Bombardier accredited. It is also Africa's largest airline. It has a good reputation.
The only thing necessary for evil to triumph is for it to be pitted against a slightly greater evil
www.nytimes.com/2019/02/03/world/asia/lion-air-plane-crash-pilots.html
to summarise: we added a few lines of code that the pilots don't know about to make the plane do something the pilots have no idea the plane might decide to try and do: ie, depending on input from one little sensor, the computer might try and shove the nose into the ground.
And the "you couldn't make this bit up" bit in the article:: on previous planes without this new software, if you felt the nose was being shoved into the ground for some unknown reason, you could (wait for it, wait for it) "pull back on the stick", and that would do what pulling back on the stick has done in aeroplanes like forever, i.e. bring the nose up (in this case, by disabling any mad sensors/sensor readings).
(If I were the one conscious person on a plane, having to fly it, that is the single thing I would know to try to do.)
But not any more - with this new feature, *that method of escape has been removed*.
- We're going to crash!
- Pull back on the stick!
- Computer says no!
To be fair: All crash landings* involve problems with vertical ascension
If you're going to be pedantic crash landings involve problems with vertical descension ;-)
Thus, it is unsurprising to see two accidents on takeoff in a row, often with completely different causes.
The problem was more specific than just "during takeoff". Both aircraft showed similar irregularities with their rate of ascent during takeoff. You are of course still right and this is still speculation, but these issues seem to have a lot in common.
No. A crashing plane is having no trouble descending.
Right, you can be sure of that.
We should continue to blame China for everything wrong on this planet, that will for sure Make America Great Again.
Over 150 people just died, which is 3 Chernobyls. This means that aviation is a dead-end technology that cannot possibly be made safe at reasonable levels of cost. Germany takes the lead, mothballing all civilian aircraft now in use. From now on, Germans will use their rail network to carry domestic traffic. For international travel, Germany will build a new fleet of ships, wind powered and made of sustainable tree derived materials.
The US will take a more measured approach. No new planes will be ordered, but airlines will continue to operate with existing craft until they age out, whereupon they will be replaced by buses. The UK will do the same, but will order one more aircraft from China, specially designed with 12 engines and parachutes for each passenger, to cost GBP 10 billion and be delivered in 2025.
My point was that this was NOT in the fine manuals, so reading them wouldn't help... It was added in August of last year, which was AFTER the crash in Indonesia.
So I'm not blaming the pilots at all, I'm saying they didn't receive the necessary information for the safe operation of the aircraft with the new system installed, likely never experienced the problem in the simulator during their training. It may be that the aircraft was airworthy and controllable, but if you don't know what to do, haven't been trained to do it, It's hard to blame the pilots for not being able to deal with the problem.
I'm also pointing towards the maintenance staff's training and the aircraft's maintenance procedure documentation. This new feature wasn't well documented there either and the Indonesian aircraft experienced multiple issues with this system, which in hindsight where likely indicators of a failing sensor, but the maintenance crews never fixed the problem, their diagnosis procedures didn't find the pending fault, so they put the aircraft back into service..
So, RTFM wouldn't have produced a different result. The information just wasn't in there.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
2 events is never enough information for you to say something math-challenged like "Most likely not a coincident."
That's just world class stupidity right there.
I say "stupidity" and not "ignorance" because I know darn well you've had basic statistics explained to you before.
Right but multiple people nearby are giving detailed descriptions of the way the plane was making a really loud shuddering sound, trailing smoke and luggage, and then the nose tipped down and it crashed.
Apparently because of the sounds, every nearby villager and cow was aware of the situation and watched the crash.
I'd take it wish a pinch of salt, but I wouldn't credit internet assumptions that the cause must be the same as something else that happened 1 time.
The problem here is how the system is designed to work and how pilots fly airplanes.
The Stall prevention system is designed to make it harder to stall the aircraft by increasing the back pressure the pilot feels as they approach the stall. So as the angle of attack increases, so does the back pressure required to maintain the pitch angle. This actually makes perfect sense as part of of the flying skill is the feel of the aircraft, the forces on your butt, the forces your hands feel all play a roll.
The problem with this system is that it messes with the pitch trim. Pilots are trained to trim the aircraft for the pitch, power and attitude settings so the yoke pressure is nearly zero. The stall avoidance system effectively messes with this trim setting and if a pilot isn't aware of what the system is doing, it's easy to get into a situation where the aircraft is badly out of trim (or at least feels that way) should the system be reacting to an error from a sensor. Where it's *possible* to fly out of trim aircraft (within acceptable pitch trim range which is based on your speed, weight and power) it is a mentally and physically demanding. Then add to the fray the confusion about why the aircraft isn't flying as it should and you are going though the fault isolation check lists, it's easy to see how a pilot might be overwhelmed. Further, it's likely that in this case the fault isolation check list didn't actually include this system failure, so the two guys up front where on their own, trying to figure out something they had no information about.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
Two early crashes in a new plane with somewhat similar circumstances is mighty suspicious and certainly warrants waiting for solid details from the investigation.