Boeing 737 MAX

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The latest MAX crash has certainly generated some concern. Friends and relatives who fly and maintain the plane seem uncertain as to whether it is design, training or maintenance related. As details emerge on Ethiopia tragedy there are statements from ground observers as to mid-air plane breakup and strange noises.

Any thoughts from TF flight professionals?
 
Won't really know until they download the recorders. Probably already done due to the pressure to sort this out.

Could be the same MCAS (??) thing that took out the Lion Air Max-8. Anti-stall goes haywire and pilots did not know to turn the system off. Flick a switch then fly the plane. Got to know to flick the switch, though.
 
..Could be the same MCAS (??) thing that took out the Lion Air Max-8. Anti-stall goes haywire and pilots did not know to turn the system off. Flick a switch then fly the plane. Got to know to flick the switch, though.
And where the switch is.
The plane is banned from operating into/out of Australia pending a fix. Many other countries too, though not Canada and USA, according to news this morning. For us, it seems to only affect Fijian Airlines,and Singapore`s Silkair subsidiary,the latter has alternative aircraft, Fijian with a small fleet will be in trouble.
 
And where the switch is.


The switch (switches, actually, it's a redundant system)is right where it's been on every 737 since Lufthansa got the first one in 1968.


In this pic, on the center console just above the big red #2 engine fire handle
 

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BTW:


Ethiopian co-pilot had 200 hours total flight time. I doubt he could even find the "Runaway Trim Checklist", let alone the Memory Items.


Not his fault, I suppose, someone must have told him he was qualified.


'Prof
 
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I have a flight planed in 4 weeks aboard one of these, if I survive I will tell you if it is flying well lol :)

L
 
Perhaps if Boeing had some indicator that there was a system over-riding pilot inputs (didn't exiist in 1968) it would give pilots a fighting chance. Kinda like the traction control light in my car...
 
Perhaps if Boeing had some indicator that there was a system over-riding pilot inputs (didn't exiist in 1968) it would give pilots a fighting chance. Kinda like the traction control light in my car...

Actually, they are writing a patch as we speak to provide an MCAS alarm, but I think an uncommanded pitch down should be alarming enough...Kinda like your car drifting sideways makes the light redundant.
 
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Lion Air had similar uncommanded pitchdown events on six consecutive flights, almost certainly initiated by a failed AOA sensor In the preceding five, the crews responded, in accord with the required procedure. What kind of company would continue to dispatch this flawed aircraft until it found a crew not up to the challenge?
 
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Whoa....probably still more to the story.
But so far from what I have read is the least trained are the issue...no aircraft is perfect even years after hard use.


Uncontrolled flight and the crew doesn't secure the autopilot? Wouldn't let them row my dingy to shore.
 
Lion Air had similar uncommanded pitchdown events on six consecutive flights, almost certainly initiated by a failed AOA sensor In the preceding five, the crews responded, in accord with the required procedure. What kind of company would continue to dispatch this flawed aircraft until it found a crew not up to the challenge?


This is the first question that one has to answer. The second question is how did the pilots loose situational control of an autopilot? Poor training? The max is not a new aircraft, its an upgrade to an existing certificate of air worthiness and even if the latest incident is related it comes back to training.
 
When we go to and from AZ we fly Allegiant Air out of our local airport. Allegiant has gotten rid of it's aging 737 fleet and has moved to an all new fleet of jets from those "other guys" over in Europe who make Airbus planes.
 
When we go to and from AZ we fly Allegiant Air out of our local airport. Allegiant has gotten rid of it's aging 737 fleet and has moved to an all new fleet of jets from those "other guys" over in Europe who make Airbus planes.

Allegiant had md80’s
 
Whoa....probably still more to the story.
But so far from what I have read is the least trained are the issue...no aircraft is perfect even years after hard use.


Uncontrolled flight and the crew doesn't secure the autopilot? Wouldn't let them row my dingy to shore.

Lion air pilots were completely innocent in my opinion. Boeing added this feature to the aircraft, wasn’t included in training nor in the acft documentation. The aircraft doesn’t tell the pilots it’s over riding their commands and it happens with autopilot OFF. Since then, a circular has been put out to all operators.
 
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A fundamental difference between design philosophies for Airbus and Boeing is that Boeing has always defaulted to pilot control in crisis situations, where Airbus prefers automatic systems. From what I have read, when Boeing decided to upgrade the 737 rather than white sheet a new design, they selected engines whose weight and size required changing the placement of the wings on the fuselage. That changed how the aircraft would respond and made it slightly more likely to pitch up during climb out, although I have no clue why that would be. Hence, the need for a system that corrects what amounts to an artifact of a bit of a kludge to accommodate new engines. The black box data should provide lots of insights, so until then, no one knows for sure what happened. However, it is possible we will never get a definitive answer that is made public. I say that based on a conversation I had with a fairly drunk Boeing technician in first class (free drinks) who was put in charge of replacing all the pylons on 747s worldwide. I asked him if he worked for Boeing because he had a whopper 3 ring binder with Boeing on the cover, and the flight we were on was returning to Seattle.

He said he did, and about 5 drinks later we got to talking about the crash of TWA 800 off New York. Many witnesses said that they observed a rocket hitting the aircraft and bringing it down, but the official explanation was an explosion in the fuel tanks. The tech confided to me - and you can take this or leave it as truth - that it was that crash that had occupied his time for the last two years. I asked why, and after pausing, he said it was because the design of the engine pylons was the actual cause. According to him, these were originally designed to break away from the wing if a bird strike or other catastrophic event damaged the turbine, which causes the engine to vibrate so much the concern was wing damage. He said that what happened to TWA 800 was a bird strike on the port outer engine. The engine broke loose as it was designed to do, but had sufficient fuel in the lines to keep burning for a few more seconds. The result was that the engine became a missile, and looped back and impacted the fuselage just forward of the wings, bringing the plane down and explaining why so many were convinced a land fired missile caused the crash.

I have no way of knowing whether this was fact or fiction, but I did verify after I got home that Boeing had, in fact, replaced all pylons on all 747s after this crash so it has the ring of truth. I mention this in context to this most recent crash because grounding the entire fleet would be almost as disruptive to air travel, world commerce, etc. as grounding all 747s would have been, which never happened. So, if I had to guess, these crashes will be put down to pilot error, but Boeing will fix whatever caused the issue and we will never get a comprehensive explanation.
 
Lion air pilots were completely innocent in my opinion. Boeing added this feature to the aircraft, wasn’t included in training nor in the acft documentation. Since then, a circular has been put out to all operators.

I believe that is incorrect. The system was not called an MCAS in the training manual, but its existence is explained, as well as the fix, which is simply flipping a switch to turn off auto trim. All modern aircraft have automatic trim capability, and all pilots should understand how to turn it off. What is new with this aircraft is the need for a response from the auto trim system when it is detected that the nose is pitching up, but not the auto trim.
 
BTW:


Ethiopian co-pilot had 200 hours total flight time. I doubt he could even find the "Runaway Trim Checklist", let alone the Memory Items.


Not his fault, I suppose, someone must have told him he was qualified.


'Prof
What were the Captain`s accrued hours to date of death?
 
I believe that is incorrect. The system was not called an MCAS in the training manual, but its existence is explained, as well as the fix, which is simply flipping a switch to turn off auto trim. All modern aircraft have automatic trim capability, and all pilots should understand how to turn it off. What is new with this aircraft is the need for a response from the auto trim system when it is detected that the nose is pitching up, but not the auto trim.

https://en.m.wikipedia.org/wiki/Lion_Air_Flight_610

Read the aftermath section about “difference training” and the changes to the flight manual.
 
What were the Captain`s accrued hours to date of death?

I think I read 8000 hours, but given that he most likely has hands on the yoke (autopilot inhibits the MCAS by design), he's relying on the hapless "passenger" in the right seat to run the memory items and the runaway trim list at a very low altitude.
 
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Whoa....probably still more to the story.
But so far from what I have read is the least trained are the issue...no aircraft is perfect even years after hard use.


Uncontrolled flight and the crew doesn't secure the autopilot? Wouldn't let them row my dingy to shore.


Actually, the aircraft were being hand-flown. The autopilot inhibits the MCAS.


The Boeing checklist for an uncommanded pitch change:

Firmly grasp the yoke
Disengage the A/T and A/P
If runaway does not stop...
Stab trim cutout switches to cutout



Pretty much the same for any airplane with electric trim, even my Piper Arrow, as I think about it.


While I have 30 years with the FAA and 10 years as a Professor of Aviation Technology, I don't claim any special knowledge of this airplane, but I have a good network, including someone who is currently flying this airplane with a US Part 121 carrier who provided this insight:


The Lion Air crew had 26 MCAS events. 25 times they did what you'd naturally do--they trimmed in the opposite direction with the yoke trim thumb switches. This stops the MCAS for five seconds. If the conditions which triggered the MCAS are still present (in this case, the bad AoA data) another 10 second MCAS activation will occur. After two or three of these cycles it should become obvious that there is a trim problem and the cutout switches should be used (the A/P must already be off as the A/P suppresses MCAS) For some reason, they never did this.
 
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The 737 stab trim cutout switches are not redundant. One switch cuts out the pilot activated trim system, the other cuts out the automatic trim system (mostly from the autopilot). The MCAS system is cut out if the stab trim cutout switches are activated (don't recall which one). The drill mentioned for runway trim (or any uncommanded trim actuation) is to cutout both systems using the switches. If the pilot's have the opportunity, the switches can be reengaged individually to see which system is causing the runway. Once the faulty system is determined, the aircraft can be flown normally using the other one.

In the event that the cutout switches do not stop the trim movement, the pilot can override the system by grabbing the manual trim wheel and holding it. Grabbing the spinning wheel can seem a little tricky, but there is a technique to doing it.

Runway trim events are part of initial and recurrent training.

Unfortunately these days, pilot training is more of rote practice of the aircraft manufacturer's procedures. If it's not on the manufacturer manual most airlines are reluctant to expand or enhance what they get in the aircraft manuals. A big part of this is liability. But it results in pilots that do not have the ability to improvise if things get out of hand and it wasn't in the manual. You'd think that if something happened 26 times in a few minutes, the pilots would have started to catch on to how to handle the problem.
 
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"A big part of this is liability. But it results in pilots that do not have the ability to improvise if things get out of hand and it wasn't in the manual."

In the past pilot training was in depth , and after transition most pilots could "build the plane", draw the basic engine, electrical, hydraulic, APU, and air pressure systems from memory.

Today its "switch position" , if moving a switch can not solve the problem ,carry on, as there is nothing you can do about it.

For decades Boeing did not install an AoA , perhaps that was a good idea?

Personally I would choose any Boeing over an Air Bust , as the flight control on Boeings is for pilots , not an automated system.
 
I know zip about flying and planes, but this is sounding like the Korean Air problem - basically inadequately trained pilots who can operate the controls, but who are challenged to actually fly the plane themselves.
 
A lot of aircraft have uncommanded inputs or unusual emergencies during their growth.


The second type USCG helo I flew would sometimes reduce lift to zero while descending under 100 feet while making a approaches to the water at night. Talk about eye openers....but we didn't crash any.


Pilots that fly new aircraft or modded should understand more than the minimum training requirements.
 
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... For decades Boeing did not install an AoA , perhaps that was a good idea?... .

At least on the 737NGs, AOA is an option. The system has it anyway and it can be displayed to the pilot on the PFD. However, it is the airlines not Boeing who choose not to enable it (it is a simple aircraft display option selection). Only a few use it, I believe AA is one.

It would be the same for any Boeing aircraft that uses the Boeing CDS system for the cockpit displays.

FWIW, most business jets have AOA displays and have had them for a long time.
 
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