I am one of the most harmless people out there. Fact is, many pilots suck and automation saves lifes. This is why an a320 is inherently safer than a 737.
It is too much plane for many routes. This is why the a310 - exactly what you propose - didn't sell that well. A wide airplane is also an inefficient airplane because of added weight and higher aerodynamic resistance. This is why airbus has killed the a319 neo, selling the narrower 2+3 a220 instead.
At least on this we agree. 737 is a shitty airplane, an ugly mess of hydraulic lines, wiring and pneumatic tubes, looking inside like a real life manifestation of spaghetti code. It is uncomfortable for the pilots, uncomfortable for the passengers and uncomfortable for the maintenance crews.
The only idiot here is you. The stab trim cutout switch has been on the 737 from the very beginning, at exactly the same place as on the 707. If the pilots didn't know about it then they never should have received their 737 type rating in the first place.
They didn't get lucky, they have recognised the situation as a runaway stabiliser and acted accordingly. No side effects whatsoever, this is how Boeing recommends to fix the situation.
This is not what happened. The pilot couldn't handle wake turbulences flipping the rudder so much that the vertical stabiliser couldn't withstand the resulting aerodynamic forces anymore. The stabiliser actually exceeded the specs, only breaking off after twice the load it was designed for (150% is required for certification). Underpowered my arse.
You are. This crash merely shows yet again that a badly trained pilot - and many of them are - will crash the aircraft as soon as something unexpected happens. The cycle repeated for 21 bloody times yet the pilot kept fighting the aircraft instead of executing the correct procedure for a runaway stabiliser (essentily flicking two switches and manually cranking the stabiliser in the correct position).
Bad pilots are a fact of life, hence the only way to protect passengers from pilots is more automation, not less.
The USSR, actually. Went from being a century behind to just about two decades behind the developed countries. Also from 20% literacy to over 99%. Even had their share of firsts. If that isn't success, then what is?
The Airbus simulation indicated that the captain's aft sidestick inputs in the last 50 feet of the flight were attenuated, limiting the ANU response of the airplane even though about 3.5[degrees] of margin existed between the airplane's AOA at touchdown (between 13[degrees] and 14[degrees]) and the maximum AOA for this airplane weight and configuration (17.5[degrees]). Airbus' training curricula does not contain information on the effects of alpha-protection mode features that might affect the airplane's response to pilot sidestick pitch inputs. The flight envelope protections allowed the captain to pull full aft on the sidestick without the risk of stalling the airplane.
That's not how it works. There are really several autopilots and each one of them uses its own ADIRU, hence its own set of sensors. It is not just a software running in two copies, these are actual separate pieces of hardware, the AP1 usually gets its information from the ADIRU1, the AP2 from the ADIRU2, but it can be switched. It wouldn't surprise me if the MCAS (which is just a glorified stick pusher as used in T-tail airplanes) is an additional piece of avionics hardware.
That's not the whole story. 737 was originally designed for unsophisticated airfields, hence Boeing placed the engines low and used a very short landing gear so aircraft mechanics wouldn't need a platform to work on the engines. That decision came back to bite them in the arse two decades later when Boeing tried to fit the CFM56 under the 737 wing. They had to modify the engine and still couldn't fit the larger fan model that fit a 707 just fine.
MCAS has only a limited authority - only up to 2.5 degrees if I remember correctly. And as for the switch, it actually is present on the 737 NG since it doesn't switch off (just) the MCAS, it completely switches off electrical trim assist.
Here: http://www.flaps2approach.com/... See that stab trim panel? That's the one. It is actually already present in the 737 classic. Even the original 737-100 from 1967 have that two switches at the same place, but the stab trim panel looks a bit different and is much narrower because it came directly from the 707 (where it also was at the same place).
I am. But then again I also know that when people say things that aren't true and are corrected, they very often make excuses that they were just joking or that it was sarcasm.
Actually these multifunction probes (Pitot, AOA and TAT) are exactly what Airbus uses on the A380 and the A350 at the very least. The A350 has three multifunctional probes and one each of single function probes.
Sorry, but this is bullshit. In the "good old days" the airplanes crashed far more often because neither the manufacturers nor the airlines gave a shit about safety. DC10 had a flaw with the cargo door the manufacturer knew about from the start. Took two crashes and a lawsuit for them to do something about it. The manufacturers only started to add hydraulic fuses to their aircraft designs after at least a thousand preventable deaths (DC10 and two 747, and that is just from the top of my head). Airlines generally only started hiring hiring better pilots and stopped skimping on the maintenance after a bad crash. Nowadays the aircraft is so expensive and the margins so tight that the airlines themselves started to insist on safety.
Moreover they have ignored proper procedures - once one pilot states that he has control and the other confirms, the other has no business of touching the sidestick and the rudder pedals. But the other pilot kept trying to fly the aircraft nonetheless. And ignored the plane saying out loud "dual input". In a Boeing he would just try to overpower the other pilot wondering the whole time why the controls are so unresponsive.
In the 1988 crash the automation saved lifes preventing the aircraft from stalling and falling down like a stone and killing all of the passengers instead of gliding on the top of the trees cushioning the impact. As for the reverse thrust and autospoiler thing, that is not an unusual problem. Even a a Tupolev once crashed that way. https://m.youtube.com/watch?v=... If I remember correctly, it happened on a barely automated MD-80 once as well, and on a 757 too. Almost all airplanes have to detect that they are on the ground before thrust reversers can be deployed and sometimes this sensor fails.
Well, while averaging the command inputs sounds ridiculous at first, there is no good solution for this. Dual input only made sense in classic aircraft with mechanical controls where it could happen in an emergency that one pilot alone wouldn't have enough strength to steer. In all other situations only one pilot must have control over the aircraft (except maybe when one of the pilots is suicidal). In a FBW aircraft no physical effort is involved so there is never need for dual input. For this reason any dual input is wrong and averaging it might mitigate a wrong input until the pilots resolve the control ownership. After hearing the "dual input" warning the pilot flying should have said something along the lines of "Dude, are you deaf? I said I have control, get your paws off the side stick!" and the situation would be resolved.
There had to be more backup instruments powered by the ram air turbine or the batteries than just two. At the very least a compass, an artificial horizon and a bank and turn indicator.
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I am one of the most harmless people out there.
Fact is, many pilots suck and automation saves lifes. This is why an a320 is inherently safer than a 737.
It is too much plane for many routes. This is why the a310 - exactly what you propose - didn't sell that well. A wide airplane is also an inefficient airplane because of added weight and higher aerodynamic resistance. This is why airbus has killed the a319 neo, selling the narrower 2+3 a220 instead.
At least on this we agree. 737 is a shitty airplane, an ugly mess of hydraulic lines, wiring and pneumatic tubes, looking inside like a real life manifestation of spaghetti code. It is uncomfortable for the pilots, uncomfortable for the passengers and uncomfortable for the maintenance crews.
The only idiot here is you. The stab trim cutout switch has been on the 737 from the very beginning, at exactly the same place as on the 707. If the pilots didn't know about it then they never should have received their 737 type rating in the first place.
They didn't get lucky, they have recognised the situation as a runaway stabiliser and acted accordingly. No side effects whatsoever, this is how Boeing recommends to fix the situation.
This is not what happened.
The pilot couldn't handle wake turbulences flipping the rudder so much that the vertical stabiliser couldn't withstand the resulting aerodynamic forces anymore. The stabiliser actually exceeded the specs, only breaking off after twice the load it was designed for (150% is required for certification). Underpowered my arse.
Is 0.2 degrees per second with a pause every ten seconds or after any trim input forcing the nose down hard?
This is why there are two pilots in the cockpit. One to fly the plane, the other for running the checklists.
You are. This crash merely shows yet again that a badly trained pilot - and many of them are - will crash the aircraft as soon as something unexpected happens. The cycle repeated for 21 bloody times yet the pilot kept fighting the aircraft instead of executing the correct procedure for a runaway stabiliser (essentily flicking two switches and manually cranking the stabiliser in the correct position).
Bad pilots are a fact of life, hence the only way to protect passengers from pilots is more automation, not less.
Show me a country that wouldn't fail in the end after a large part of the world wages an economic war against it.
The USSR, actually.
Went from being a century behind to just about two decades behind the developed countries. Also from 20% literacy to over 99%. Even had their share of firsts. If that isn't success, then what is?
From the actual NTSB report on this:
Emphasis mine.
Explain this then:
https://en.wikipedia.org/wiki/...
And while they wait they buy Toyota hybrids for the next 20 years or so.
That's not how it works.
There are really several autopilots and each one of them uses its own ADIRU, hence its own set of sensors. It is not just a software running in two copies, these are actual separate pieces of hardware, the AP1 usually gets its information from the ADIRU1, the AP2 from the ADIRU2, but it can be switched. It wouldn't surprise me if the MCAS (which is just a glorified stick pusher as used in T-tail airplanes) is an additional piece of avionics hardware.
That's not the whole story.
737 was originally designed for unsophisticated airfields, hence Boeing placed the engines low and used a very short landing gear so aircraft mechanics wouldn't need a platform to work on the engines. That decision came back to bite them in the arse two decades later when Boeing tried to fit the CFM56 under the 737 wing. They had to modify the engine and still couldn't fit the larger fan model that fit a 707 just fine.
Actually yes. Most airliners have two autopilots - left and right. Some have an additional center autopilot.
MCAS has only a limited authority - only up to 2.5 degrees if I remember correctly. And as for the switch, it actually is present on the 737 NG since it doesn't switch off (just) the MCAS, it completely switches off electrical trim assist.
Here: http://www.flaps2approach.com/...
See that stab trim panel? That's the one. It is actually already present in the 737 classic. Even the original 737-100 from 1967 have that two switches at the same place, but the stab trim panel looks a bit different and is much narrower because it came directly from the 707 (where it also was at the same place).
I am. But then again I also know that when people say things that aren't true and are corrected, they very often make excuses that they were just joking or that it was sarcasm.
Actually these multifunction probes (Pitot, AOA and TAT) are exactly what Airbus uses on the A380 and the A350 at the very least. The A350 has three multifunctional probes and one each of single function probes.
Sorry, but this is bullshit. In the "good old days" the airplanes crashed far more often because neither the manufacturers nor the airlines gave a shit about safety. DC10 had a flaw with the cargo door the manufacturer knew about from the start. Took two crashes and a lawsuit for them to do something about it. The manufacturers only started to add hydraulic fuses to their aircraft designs after at least a thousand preventable deaths (DC10 and two 747, and that is just from the top of my head). Airlines generally only started hiring hiring better pilots and stopped skimping on the maintenance after a bad crash. Nowadays the aircraft is so expensive and the margins so tight that the airlines themselves started to insist on safety.
Moreover they have ignored proper procedures - once one pilot states that he has control and the other confirms, the other has no business of touching the sidestick and the rudder pedals. But the other pilot kept trying to fly the aircraft nonetheless. And ignored the plane saying out loud "dual input". In a Boeing he would just try to overpower the other pilot wondering the whole time why the controls are so unresponsive.
In the 1988 crash the automation saved lifes preventing the aircraft from stalling and falling down like a stone and killing all of the passengers instead of gliding on the top of the trees cushioning the impact.
As for the reverse thrust and autospoiler thing, that is not an unusual problem. Even a a Tupolev once crashed that way.
https://m.youtube.com/watch?v=...
If I remember correctly, it happened on a barely automated MD-80 once as well, and on a 757 too. Almost all airplanes have to detect that they are on the ground before thrust reversers can be deployed and sometimes this sensor fails.
Well, while averaging the command inputs sounds ridiculous at first, there is no good solution for this.
Dual input only made sense in classic aircraft with mechanical controls where it could happen in an emergency that one pilot alone wouldn't have enough strength to steer. In all other situations only one pilot must have control over the aircraft (except maybe when one of the pilots is suicidal). In a FBW aircraft no physical effort is involved so there is never need for dual input. For this reason any dual input is wrong and averaging it might mitigate a wrong input until the pilots resolve the control ownership. After hearing the "dual input" warning the pilot flying should have said something along the lines of "Dude, are you deaf? I said I have control, get your paws off the side stick!" and the situation would be resolved.
There had to be more backup instruments powered by the ram air turbine or the batteries than just two. At the very least a compass, an artificial horizon and a bank and turn indicator.