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Ethiopian Airlines 737 Max crashes killing 157


Nueces River Rat

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In the news tonight an air industry expert said that the other 737 Max crash in Asia was due to an automation feature on the jet that sensed the plane was stalling and implemented automatic nose down maneuvers. The pilots tried to counteract it, but didn’t know about this anti-stall feature and fought it all the way to the ground. Wondering whether the new anti-stall automated pilot feature has a bug.

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13 hours ago, Onboard 2.0 said:

On reflection, flying out of 3rd world nations is probably safer than staying in some 3rd world nations.

Meh, if you haven't stayed a few days or a week or a month or a year in a third world nation you haven't really lived. Or at the very least haven't appreciated how you have lived.

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13 hours ago, Onboard 2.0 said:

On reflection, flying out of 3rd world nations is probably safer than staying in some 3rd world nations.

Meh, if you haven't stayed a few days or a week or a month or a year in a third world nation you haven't really lived. Or at the very least haven't appreciated how you have lived.

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8 hours ago, Dbeasy said:

In the news tonight an air industry expert said that the other 737 Max crash in Asia was due to an automation feature on the jet that sensed the plane was stalling and implemented automatic nose down maneuvers. The pilots tried to counteract it, but didn’t know about this anti-stall feature and fought it all the way to the ground. Wondering whether the new anti-stall automated pilot feature has a bug.

Wouldn't your first recovery move be turn off auto pilot? /dumbquestionamnesty

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20 hours ago, Pato del Muerto said:

Getting on, or in rather, a couple of planes today. Glad the crash is out of the way, the odds of two crashes in one day seem remote. 

Long awaited update is that we indeed did not crash. 

Post script:  all the toilets stopped functioning while the plane was halfway across the Atlantic.  So the flight was not without incident.  Active measures taken by the crew included keeping the lights off through sunrise to keep as many people asleep for as long as possible, and cancelling breakfast service, as well as calling heathrow to request priority landing and gate service. 

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4 hours ago, NotActuallyALonghorn said:

Meh, if you haven't stayed a few days or a week or a month or a year in a third world nation you haven't really lived. Or at the very least haven't appreciated how you have lived.

Does Louisiana count?

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58 minutes ago, RPM said:

Wouldn't your first recovery move be turn off auto pilot? /dumbquestionamnesty

One thing I learned from the AF447 crash is that planes have different levels (I think they are called “laws”) of automation. So they could have been on a level where the pilot has to do everything, BUT if the avionics detects a stall it will still try to save the plane. Seems to be similar to modern cars where you can easily turn off some nannies, but others such as emergency braking can be almost impossible to turn off.

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Wouldn't your first recovery move be turn off auto pilot? /dumbquestionamnesty

Yes.

Step 1) auto pilot off

2) oppose trim with control column. There's a breaking mechanism built into this movement to stop stabilizer trim movement.

3) if 1 and 2 don't work stab trim switches off.

 

This has been the procedure for 50 years on this airplane for a runaway trim condition. The MCAS didn't fail in the Lion air accident. It just responded to what a bad angle of attack indicator was telling it.

 

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5 hours ago, NotActuallyALonghorn said:

Meh, if you haven't stayed a few days or a week or a month or a year in a third world nation you haven't really lived. Or at the very least haven't appreciated how you have lived.

Been to SA, and while its not a 3rd world nation I have spent quite a bit of time in the informal housing settlements around the country. My post was sarcasm first and foremost.

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1 hour ago, Pato del Muerto said:

Long awaited update is that we indeed did not crash. 

Post script:  all the toilets stopped functioning while the plane was halfway across the Atlantic.  So the flight was not without incident.  Active measures taken by the crew included keeping the lights off through sunrise to keep as many people asleep for as long as possible, and cancelling breakfast service, as well as calling heathrow to request priority landing and gate service. 

Sounds shitty.

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3 hours ago, RPM said:

Wouldn't your first recovery move be turn off auto pilot? /dumbquestionamnesty

There’s a lot of automation separate from the autopilot. That nose down auto trim happens whether the autopilot is on or off. 

But yeah, the problem sounds like it presents like a standard runaway trim. Running the most basic of memory items should have stopped it. 

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3 hours ago, XYZ said:

One thing I learned from the AF447 crash is that planes have different levels (I think they are called “laws”) of automation. So they could have been on a level where the pilot has to do everything, BUT if the avionics detects a stall it will still try to save the plane. Seems to be similar to modern cars where you can easily turn off some nannies, but others such as emergency braking can be almost impossible to turn off.

The Airbus has laws since it is a fly by wire airplane with a computer in between the pilot inputs and the controls surface. 7 actually. The laws determine what level of protections are provided, and one can get into a lesser law level by turning things off to overcome erroneous contour inputs. Once in a lower law you cannot get back into a higher law. You’re technically not supposed to be able  to stall an Airbus in the highest law known as normal law. 

One if the pilots in AF447 held full nose up input nearly until impact. In normal law the low speed/high angle of attack protections should have prevented the plane from stalling. But the plane also had frozen air data sensors and was likley in abnormal law (no protections and used for unusual attitude recovery) once control was lost so the pilot pulling nose up was only exacerbating the problem. The other pilot has no physical indication of the opposite stick inputs, and both stick inputs are summed and sent to the flight controls. There’s is a visual and aural warning in that case however. 

Theres is also a procedure for erroneous sensors in the Airbus, and knowing pitch attitude and power settings might have saved the day. For example, 2-3 degrees of nose up and 74% N2 would yield 245 knots and level flight in the 330 family. 

The 737 does not operate on those principles. 

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3 minutes ago, Bobby_Batronic said:

The Airbus has laws since it is a fly by wire airplane with a computer in between the pilot inputs and the controls surface. 7 actually. The laws determine what level of protections are provided, and one can get into a lesser law level by turning things off to overcome erroneous contour inputs. Once in a lower law you cannot get back into a higher law. You’re technically not supposed to be able  to stall an Airbus in the highest law known as normal law. 

One if the pilots in AF447 held full nose up input nearly until impact. In normal law the low speed/high angle of attack protections should have prevented the plane from stalling. But the plane also had frozen air data sensors and was likley in abnormal law (no protections and used for unusual attitude recovery) once control was lost so the pilot pulling nose up was only exacerbating the problem. The other pilot has no physical indication of the opposite stick inputs, and both stick inputs are summed and sent to the flight controls. There’s is a visual and aural warning in that case however. 

Theres is also a procedure for erroneous sensors in the Airbus, and knowing pitch attitude and power settings might have saved the day. For example, 2-3 degrees of nose up and 74% N2 would yield 245 knots and level flight in the 330 family. 

The 737 does not operate on those principles. 

Thanks for the explanation. Does the 737 have “nannies” that try to take over for example if a stall is detected?

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4 hours ago, Pato del Muerto said:

Long awaited update is that we indeed did not crash. 

Post script:  all the toilets stopped functioning while the plane was halfway across the Atlantic.  So the flight was not without incident.  Active measures taken by the crew included keeping the lights off through sunrise to keep as many people asleep for as long as possible, and cancelling breakfast service, as well as calling heathrow to request priority landing and gate service. 

What the hell did everyone do? Surely a handful of people ended up shitting in vomit bags, right?

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30 minutes ago, XYZ said:

Thanks for the explanation. Does the 737 have “nannies” that try to take over for example if a stall is detected?

The Max apparently has one, but as  suggested above, there’s a long standing procedure to override erroneous pitch inputs in that plane as well. 

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43 minutes ago, Parliament said:

Looks like they fixed the problem and all the planes are back in the air.

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Could be worse - I remember a flight I took in the early 1980's, and we had boarded when they announce a delay due to mechanical issues. Truck drives up, couple of guys get out and look at the flaps; one of them takes out a hammer (like a 3lb hand held sledge) and hits the wing/flap/??? about 8-10 times. They look it over, the flaps are moved up & down, they pack up their shit and 20 minutes later we are on our way.
I have never been so excited to land in New Jersey in my entire life.

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13 minutes ago, Wally Fairway said:

Could be worse - I remember a flight I took in the early 1980's, and we had boarded when they announce a delay due to mechanical issues. Truck drives up, couple of guys get out and look at the flaps; one of them takes out a hammer (like a 3lb hand held sledge) and hits the wing/flap/??? about 8-10 times. They look it over, the flaps are moved up & down, they pack up their shit and 20 minutes later we are on our way.
I have never been so excited to land in New Jersey in my entire life.

And you're the only person to have said it.

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20 hours ago, RPM said:

Saw this earlier.

JAMAICA, Queens (WABC) -- 30 people were injured after heavy turbulence on board a Turkish Airlines flight from Istanbul that landed at JFK Airport on Saturday evening, officials say. 

28 passengers and two crew members were being evaluated on the scene for non-life threatening injuries just before 6 p.m. Ten people were taken to the hospital. Some passengers hit their heads on the ceiling of the plane. 

Passengers say the heart-pounding turbulence lasted for about six minutes. When it was over, every other row had someone either injured or bleeding. Officials say severe turbulence caused bruises, cuts, a broken leg and gashes on some passengers' heads. 

An apparent airline crew member was seen limping out of the terminal with a bandage around his leg. 

Several small children were also in need of medical attention. 

The plane with 326 passengers on board was over Maine when it happened. 
 

This is why you keep your seat belt on when seated, at least loose, and only get up when really necessary. Fucking stupid people. Jesus.

Edited by wood
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Interesting comments from the obvious pilots on here. I had heard that the plane rides we take these days are so automated that if the laymen knew how little a pilot does they would psychologically not be able to handle it and it would hurt the industry. Is that true? You can almost have a plane fly itself end to end?

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14 minutes ago, Rougarou said:

Interesting comments from the obvious pilots on here. I had heard that the plane rides we take these days are so automated that if the laymen knew how little a pilot does they would psychologically not be able to handle it and it would hurt the industry. Is that true? You can almost have a plane fly itself end to end?

It don't make a shit to me... just fucking get there.

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18 minutes ago, Rougarou said:

Interesting comments from the obvious pilots on here. I had heard that the plane rides we take these days are so automated that if the laymen knew how little a pilot does they would psychologically not be able to handle it and it would hurt the industry. Is that true? You can almost have a plane fly itself end to end?

For the pilots here, what is the advantage of the aircraft taking over as opposed to having instruments keep track of stall speed and letting the pilots monitor that?

I'm sure there were reasons, but I wonder if you have an opinion on it.

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1 hour ago, retread said:

For the pilots here, what is the advantage of the aircraft taking over as opposed to having instruments keep track of stall speed and letting the pilots monitor that?

I'm sure there were reasons, but I wonder if you have an opinion on it.

The short answer is that they are trying to idiot proof the plane. There are graphic descriptions on the airspeed indicator that the pilots do monitor stall speed with (which varies quite a bit based on a lot of factors l), and crews are trained at every recurrent event to recover from the stall. The FAA has mandated enhanced envelope training whereby more in depth training is had in more dynamic scenarios as well. That’s going into effect this year. 

Another nice thing about the automation would be a terrain avoidance maneuver. Under normal law protections the pilot can pull full aft of on the control stick and the plane will climb rapidly before reaching a maximum angle of attack, and will not exceed that angle so there is no worryof stalling the plane in the escape profile.  

Lastly, while many could turn the AP on at 50 feet on takeoff and let the plane auto land at a properly equipped airport it just doesn’t happen that way. I find that most people hand fly the plane from anywhere between 7,000-24,000 feet on climb out, and virtually everyone has the AP turned off by at least 1000 feet above the ground in landing with many turning it and the auto thrust off well before then. 

The automation weakens your hand flying skills, so it’s up to you to stay sharp, but it also allows you to step back and monitor the situation with greater situational awareness while not being task saturated by manually flying the plane. 

Edited by Bobby_Batronic
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1 hour ago, Rougarou said:

Interesting comments from the obvious pilots on here. I had heard that the plane rides we take these days are so automated that if the laymen knew how little a pilot does they would psychologically not be able to handle it and it would hurt the industry. Is that true? You can almost have a plane fly itself end to end?

There is a lot of automation but it doesn't always make things easier, it just gives you a different set of tasks.  There are nearly 20 buttons and knobs on the autopilot panel and they all get manipulated in different orders and ways for different scenarios.  You don't just flip it on and sit back.  There are dozens of different modes and ways to climb, descend, join a course, control the speed, rates of climb/descent, etc... and a different choice is appropriate each different scenarios.  The descent on one flight might be managed completely different from the descent on the prior flight depending on lots of different factors.  It's lot harder to learn to how to manage all that automation than it is to learn to pitch and roll with stick and rudder skills.  The automation ultimately makes it safer, when used correctly, but it doesn't make it necessarily easier.   Pilots screwing up the automation is a much more  common cause of accidents than poor hand-flying skills.  The pilot is being paid for the experience he uses to make decisions, not for the stick and rudder stuff.   

My truck has cruise control, lane-assist, and auto braking.  I'm sure my 11 year old could keep it straight going down a highway if I let him, probably could even negotiate a few turns and stops.  But that doesn't mean I'd let him take it through Chicago during rush-hour in bad weather.  

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Autopilot is great cross country. I like to fly with flight director during climb out and approach into airport, weather permitting

Its pretty badass what automation is available in GA now. LPV takes you within 200 ft AGL in airports that are outfitted; completely Sat based. Pretty awesome and it costs ~$100k to install today. 

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2 hours ago, Your Mom said:

There is a lot of automation but it doesn't always make things easier, it just gives you a different set of tasks.  There are nearly 20 buttons and knobs on the autopilot panel and they all get manipulated in different orders and ways for different scenarios.  You don't just flip it on and sit back.  There are dozens of different modes and ways to climb, descend, join a course, control the speed, rates of climb/descent, etc... and a different choice is appropriate each different scenarios.  The descent on one flight might be managed completely different from the descent on the prior flight depending on lots of different factors.  It's lot harder to learn to how to manage all that automation than it is to learn to pitch and roll with stick and rudder skills.  The automation ultimately makes it safer, when used correctly, but it doesn't make it necessarily easier.   Pilots screwing up the automation is a much more  common cause of accidents than poor hand-flying skills.  The pilot is being paid for the experience he uses to make decisions, not for the stick and rudder stuff.   

Image result for office space people person

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8 hours ago, Rougarou said:

 I had heard that the plane rides we take these days are so automated that if the laymen knew how little a pilot does they would psychologically not be able to handle it and it would hurt the industry. Is that true?

Buddy of mine was training United pilots on how to fly the 787 when it was brand new. He got me in the simulator at IAH. With zero flying experience, I was able to taxi to the runway, take off, fly to downtown Houston, then land. Over course he was standing right behind me telling me what to do. It seemed awfully easy though. Of course I wasn’t dealing with any abnormal circumstances. 

I shot this video of my other buddy landing the same simulator:

My landing was smoother than this one. Once on the runway though, I forgot (until reminded) that I needed to steer with my feet. Made things a bit interesting careening down the runway swaying left and right.

Captain Obvious: flying the sim was awesome, unbelievably realistic.

Random Fact: the steering wheel used to steer the plane out to the runway was this tiny little thing about the size of a door knob. 

Bernard

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