So what is Boeing doing about the 737 MAX?

In the wake of two recent major crashes and the subsequent grounding of the entire 737 MAX fleet worldwide, Boeing has been scrambling to get back on its feet.

Yesterday Boeing CEO, Dennis Muilenburg, released a statement. In this release Muilenburg stated...

...

The full details of what happened in the two accidents will be issued by the government authorities in the final reports, but, with the release of the preliminary report of the Ethiopian Airlines Flight 302 accident investigation, it’s apparent that in both flights the Maneuvering Characteristics Augmentation System, known as MCAS, activated in response to erroneous angle of attack information.

...

You can read the full statement here...

Boeing Update

This statement goes on to say...

From the days immediately following the Lion Air accident, we’ve had teams of our top engineers and technical experts working tirelessly in collaboration with the Federal Aviation Administration and our customers to finalize and implement a software update that will ensure accidents like that of Lion Air Flight 610 and Ethiopian Airlines Flight 302 never happen again.

Notice the words here..."From the days immediately following the Lion Air accident, we've had teams...working...with the Federal Aviation Administration and our custmers to finalize and implement a software update..." (just cutting out the fluff for clarity)

So Boeing knew there was a serious problem with their flight control system. The FAA knew there was a problem. And the Airlines (Boeing's 'customers') knew there was a problem. They knew there was a problem serious enough to make the aircraft crash unexpectedly all on its own. And, all of them knew there was a problem 'immediately following' the Lion Air accident (not the Ethiopian incident, but the Lion Air accident). Yet the MAX kept on flying.

The very next paragraph of the statement says...

We’re taking a comprehensive, disciplined approach, and taking the time, to get the software update right. ...

Okay, great. Thanks. But what about all the millions of people who flew on the other (370) 737 MAX aircraft which had been delivered, after the Lion Air crash?

In a separate statement, also issued by Boeing yesterday, Boeing stated...

...
The preliminary report contains flight data recorder information indicating the airplane had an erroneous angle of attack sensor input that activated the Maneuvering Characteristics Augmentation System (MCAS) function during the flight, as it had during the Lion Air 610 flight.

To ensure unintended MCAS activation will not occur again, Boeing has developed and is planning to release a software update to MCAS and an associated comprehensive pilot training and supplementary education program for the 737 MAX. ...

Note - You can read this second statement by Boeing in its entirety at the same link I posted above.

Here again, we have Lion Air 610 mentioned, and this time '...unintended MCAS activation...'

So what exactly is this "software update" anyway?

Well, here's what Boeing has to say about it. It will accomplish 3 basic things...

1. Flight control system will now compare inputs from both AOA sensors. If the sensors disagree by 5.5 degrees or more with the flaps retracted, MCAS will not activate. An indicator on the flight deck display will alert the pilots.

2. If MCAS is activated in non-normal conditions, it will only provide one input for each elevated AOA event. There are no known or envisioned failure conditions where MCAS will provide multiple inputs.

3. MCAS can never command more stabilizer input than can be counteracted by the flight crew pulling back on the column. The pilots will continue to always have the ability to override MCAS and manually control the airplane.

(also at the link above (scroll down)).

Now let's examine these things a little more closely...

1. Shouldn't the sensors have always compared more than one input before making un-commanded flight control inputs? There's two of the best sensors of all sitting right on the flight deck, they're called the pilots. Why not two sensor comparisons before taking control away from those two pilots?

2. The first part doesn't even make sense. The fundamental purpose of MCAS is to activate in a non-normal condition. A stall is a non-normal condition. Okay, so now the MCAS is only going to provide one control input as opposed to numerous and continued control inputs. Shouldn't it always have been this way?

3. This one is the clincher. Boeing has basically acknowledging that MCAS is capable of overpowering flight crew inputs and effectively prohibiting critical flight control input. Wow! Warnings are one thing, but control? From not one, but two pilots?

Yet this plane has still been flying since the Lion Air 610 incident. Not only that, but yours truly flew on one during this time span too...and we had some kind of an anomaly gaining altitude right after takeoff too.

Is Boeing completely to blame? No, they're not. Boeing is not alone in the blame because both the FAA and the greedy Airlines are complicit in this as well.

Seems to me a whole lot of folks have got a whole bunch of explainin' to do.

Shouldn't the sensors have always compared more than one input before making un-commanded flight control inputs?

That was surprising to me. Redundancy is a good thing.

They are trying to blow everything off and shift the blame to the plane hitting a bird or something on takeoff'

If technology can't handle hitting a tweety bird, then maybe technology needs to be scrutinized all together. With all this technology these days, we are having way more air crashes than we ever had, something is seriously wrong in the world, people cannot see that when you make something more complicated it means that a failure of sensors can cause more problems than if things were simple.

If you buy an older car full of technology, you find that they become a money pit because of all the maintence. There is more to go wrong, buy an older car with very little technology and you can afford to keep good tires on the car because you are not broke from buying sensors. Sure the efficiency of cars is good when you buy them, but all those connectors can get corroded, leading to a car that is not energy efficient. Same with Jets. Boeing sells the parts to fix these jets, it is a big part of their income.

Probably going through all documentation and notes they have on that part to see if they missed something.
Then they will redesign the part and fix the problem.
Outside of that what can they do?

Well the gist of what I have heard from various sources is that the crash is down to the software acting repeatedly on the information from the sensor at the front side, or sides. That sensor wrongly interpreted the aircraft was flying in a nose-up angle when it was in fact flying in a normal neutral attitude, thereby forcing the aircraft to actually dive, ultimately without any way of recovery. The crew must have been doing something with the controls that slowed the process down since the plane seems to have dived in a stepped fashion, though it seems it did hit the ground in a nose dive.

What they do about the 'oversize' engines I have no idea, while I'm sure they need to do a big rethink on the wisdom of fitting them in the first place since they are the reason the plane wants to assume a nose-up possible stall attitude, requiring that bit of software to activate....

Software,
Sensor/s
Engines....too much to depend on without human input.

a reply to: rickymouse

Actually, they aren't. They said the FDR didn't show sign of a bird strike, but they haven't explained the sensor malfunction yet. It could be the sensor, or it could be the data unit itself.

a reply to: Flyingclaydisk

Please note that they will say little about possible pilot error if there was any because that would be blaming their customer for the crash and they do not want to offend the customer.
Their findings if it includes any errors will be very carefully worded.

a reply to: smurfy

According to a report yesterday, the 737 Classic had a condition where the electric trim would stop working under similar conditions that both Lion Air and Ethiopian saw. Both the NG and Max flight manuals make no mention of that condition.

Turning off the stabilizer trim stopped MCAS, but if the electric trim stopped working, which reading the preliminary report it did, the crew may have turned the power back on to try to get the stabilizer moving again, and reactivated MCAS.

a reply to: Flyingclaydisk

Ever read Michael Crichton's "Airframe"
It could have been written about this very thing.
Right down to an uncommanded flaps deployment.

In the novel it turned out to be both a software problem and pilot error.

The manufacturer emphasized the software issue.
Don't want to unduly upset a paying customer.

In reality the wide body goes for between 100 and 400 million each.
and Boeing had them lined up for the 737 MAX 10 and MAX 8 in the hundreds in 2017.

Where are all of those planes today and are they being recalled so to speak. I think the manufacturer recommends upgrades and its up to the airlines whether they install them but I dont know if they get a choice in an instance like this.
Right now the fleet is grounded.
Boeing stock is falling.

From a pal of mine:

Boeing has announced its vindication over the pesky software problem that has caused its planes to occasionally fall out of the sky. Dennis Muilenberg, CEO of Boeing: "We've updated the flight crew handbooks. White knuckled pilots can now directly contact our call center in Mumbai, India. We've been assured that wait times will not exceed five minutes, and if necessary, the pilots may ask to speak to a supervisor."

Transcript of recent call made by a pilot of a 737 Max 8:

"This is Joe, how may I be of help to you today?"

Pilot: "The plane is out of control! It keeps making uncommanded dives no matter how hard I pull back on the controls! The nose won't stop dipping!"

Joe: "I am pleased to be helping you with your problem. I am hearing you say that you have a dripping nose?"

Pilot: ".... losing altitude .... speed increasing ..... stick shaker active....."

Joe: "Okay, I see that your airplane is having the newest MCAS software. Is this what you are calling about today, sir?"

Pilot: "..... now below 5,000 feet....." controls unresponsive...."

Joe: "Have you tried rebooting the computer, sir? If you like I will now talk you through the procedure. Hello? Hello?"

a reply to: Flyingclaydisk

To ensure unintended MCAS activation will not occur again, Boeing has developed and is planning to release a software update to MCAS and an associated comprehensive pilot training and supplementary education program for the 737 MAX. ...

See the part about comprehensive pilot training?
(bold mine)
Is it possible that the system was disabled?

a reply to: Sillyolme

Well, they will have to clearly identify the problem and correct it. No, at this point there really isn't any other choice, well at least not a viable one for Boeing.

To me though, the larger issue is how the traveling public was hoodwinked for nearly a year by not only Boeing, but the FAA and the Airlines who were all aware of the issue. They may not have been aware it was as serious as it is, but there were aware of it, and the airlines in particular absolutely knew about the optional equipment (which they didn't purchase).

a reply to: Sillyolme

Actually, quite the opposite. Boeing would much rather be able to pin this on pilot error as opposed to the problem being one of their own making and design.

a reply to: TheTruthRocks

The automated system that makes you want to smash your phone.
LOL
Very funny.

a reply to: Sillyolme

Technically I would say, yes. Legally, I would say no.

The MCAS system was required for the FAA to grant the Part 25 Certification. Without this certification the plane is not 'certified' to fly.

a reply to: Sillyolme

I'm not sure if I understand your question.

Are you asking if MCAS was disabled during the Ethiopian crash? If so, yes and no, it was apparently disabled and enabled several times, according to some of the recent information.

a reply to: Zaphod58

Which sounds increasingly like what happened.

a reply to: Flyingclaydisk

Thats what I am talking about. Systems that are options for the customer.
Its often up to them to purchase upgrades or not.
The manufacturer can only recommend. They have no say in whether a plane is allowed to fly or not and believe it or not the FAA isnt the last word either because europe has their own version of an FAA and so does India and China. They would all have to agree on whether an aircraft gets certification or not. And they do not.

a reply to: Sillyolme

Where are all of those planes today and are they being recalled so to speak. I think the manufacturer recommends upgrades and its up to the airlines whether they install them but I dont know if they get a choice in an instance like this. Right now the fleet is grounded

Those are some key questions right now.

I believe the grounding allowed for one additional flight (with no PAX) to get the equipment to another location. Some airlines flew them back to their heavy maintenance facilities. Other airlines like SWA flew them to the desert for holding.

originally posted by: Flyingclaydisk
1. Shouldn't the sensors have always compared more than one input before making un-commanded flight control inputs? There's two of the best sensors of all sitting right on the flight deck, they're called the pilots. Why not two sensor comparisons before taking control away from those two pilots?

Used to work in aircraft design (military not civilian but was headhunted by Boeing). I've never heard of a sensor not having a back up device or secondary measurement reading to avoid catastrophic incidents such as these (not only in planes, basic principle of design is to have a failsafe). Cockpit isn't my forte but a lack of a manual reset or override in the event of system malfunction seems equally bizarre.

Surprised they're not going over the whole design with a fine toothcomb, basic errors like that should never even occur in design process let alone make it to the end product.