Boeing 737 Max Unsafe to Fly: New Scathing Report by Pilot and Software Designer

-edited

A pilot with 30 years of flying experience and 40 years of design experience rips decisions made by Boeing and the FAA.

Gregory Travis, a software developer and pilot for 30 years wrote a scathing report on the limitations of the 737, and the arrogance of software developers unfit to write airplane code.

Travis provides easy to understand explanations including a test you can do by sticking your hand out the window of a car to demonstrate stall speed.

Design shortcuts meant to make a new plane seem like an old, familiar one are to blame.

This was all about saving money. Boeing and the FAA pretend the 737-Max is the same aircraft as the original 737 that flew in 1967, over 50 years ago.

Travis was 3 years old at the time. Back then, the 737 was a smallish aircraft with smallish engines and relatively simple systems. The new 737 is large and complicated.

Boeing cut corners to save money. Cutting corners works until it fails spectacularly.

Aerodynamic and Software Malpractice

Please consider How the Boeing 737 Max Disaster Looks to a Software Developer. Emphasis is mine.

The original 737 had (by today’s standards) tiny little engines, which easily cleared the ground beneath the wings. As the 737 grew and was fitted with bigger engines, the clearance between the engines and the ground started to get a little…um, tight.

With the 737 Max, the situation became critical. The engines on the original 737 had a fan diameter (that of the intake blades on the engine) of just 100 centimeters (40 inches); those planned for the 737 Max have 176 cm. That’s a centerline difference of well over 30 cm (a foot), and you couldn’t “ovalize” the intake enough to hang the new engines beneath the wing without scraping the ground.

The solution was to extend the engine up and well in front of the wing. However, doing so also meant that the centerline of the engine’s thrust changed. Now, when the pilots applied power to the engine, the aircraft would have a significant propensity to “pitch up,” or raise its nose. This propensity to pitch up with power application thereby increased the risk that the airplane could stall when the pilots “punched it”

Worse still, because the engine nacelles were so far in front of the wing and so large, a power increase will cause them to actually produce lift, particularly at high angles of attack. So the nacelles make a bad problem worse.

I’ll say it again: In the 737 Max, the engine nacelles themselves can, at high angles of attack, work as a wing and produce lift. And the lift they produce is well ahead of the wing’s center of lift, meaning the nacelles will cause the 737 Max at a high angle of attack to go to a higher angle of attack. This is aerodynamic malpractice of the worst kind.

It violated that most ancient of aviation canons and probably violated the certification criteria of the U.S. Federal Aviation Administration. But instead of going back to the drawing board and getting the airframe hardware right, Boeing relied on something called the “Maneuvering Characteristics Augmentation System,” or MCAS.

It all comes down to money, and in this case, MCAS was the way for both Boeing and its customers to keep the money flowing in the right direction. The necessity to insist that the 737 Max was no different in flying characteristics, no different in systems, from any other 737 was the key to the 737 Max’s fleet fungibility. That’s probably also the reason why the documentation about the MCAS system was kept on the down-low.

Put in a change with too much visibility, particularly a change to the aircraft’s operating handbook or to pilot training, and someone—probably a pilot—would have piped up and said, “Hey. This doesn’t look like a 737 anymore.” And then the money would flow the wrong way.

When the flight computer trims the airplane to descend, because the MCAS system thinks it’s about to stall, a set of motors and jacks push the pilot’s control columns forward. It turns out that the Elevator Feel Computer can put a lot of force into that column—indeed, so much force that a human pilot can quickly become exhausted trying to pull the column back, trying to tell the computer that this really, really should not be happening.

MCAS is implemented in the flight management computer, even at times when the autopilot is turned off, when the pilots think they are flying the plane. In a fight between the flight management computer and human pilots over who is in charge, the computer will bite humans until they give up and (literally) die. Finally, there’s the need to keep the very existence of the MCAS system on the hush-hush lest someone say, “Hey, this isn’t your father’s 737,” and bank accounts start to suffer.

Those lines of code were no doubt created by people at the direction of managers.

In a pinch, a human pilot could just look out the windshield to confirm visually and directly that, no, the aircraft is not pitched up dangerously. That’s the ultimate check and should go directly to the pilot’s ultimate sovereignty. Unfortunately, the current implementation of MCAS denies that sovereignty. It denies the pilots the ability to respond to what’s before their own eyes.

In the MCAS system, the flight management computer is blind to any other evidence that it is wrong, including what the pilot sees with his own eyes and what he does when he desperately tries to pull back on the robotic control columns that are biting him, and his passengers, to death.

The people who wrote the code for the original MCAS system were obviously terribly far out of their league and did not know it. How can they can implement a software fix, much less give us any comfort that the rest of the flight management software is reliable?

So Boeing produced a dynamically unstable airframe, the 737 Max. That is big strike No. 1. Boeing then tried to mask the 737’s dynamic instability with a software system. Big strike No. 2. Finally, the software relied on systems known for their propensity to fail (angle-of-attack indicators) and did not appear to include even rudimentary provisions to cross-check the outputs of the angle-of-attack sensor against other sensors, or even the other angle-of-attack sensor. Big strike No. 3.

None of the above should have passed muster. It is likely that MCAS, originally added in the spirit of increasing safety, has now killed more people than it could have ever saved. It doesn’t need to be “fixed” with more complexity, more software. It needs to be removed altogether.

Numerous Bad Decisions at Every Stage

Ultimately 346 people are dead because of really bad decisions, software engineer arrogance, and Boeing's pretense that the 737 Max is the same aircraft as 50 years ago.

It is incredible that the plane has two sensors but the system only uses one. A look out the window was enough to confirm the sensor was wrong.

Boeing also offered "cheap" versions of the aircraft without some controls. The two crashed flights were with the cheaper aircraft.

An experienced pilot with adequate training could have disengaged MACS but in one of the crashed flights, the pilot was desperately reading a manual trying to figure out how to do that.

Flight Stall Test

If you stick you hand out the window of a car and your hand is level to the ground. You have a low angle of attack. There is no lift. Tilt your hand a bit and you have lift. Your arm will rise.

When the angle of attack on the wing of an aircraft is too great the aircraft enters aerodynamic stall. The same thing happens with your hand out a car window.

At a steep enough angle your arm wants to flop down on the car door.

The MACS software overrides what a pilot can see by looking out the window.

Useless Manuals

If you need a manual to stop a plane from crashing mid-flight, the manual is useless. It's already too late. The pilot had seconds in which to react. Yet, instead of requiring additional training, and alerting pilots of the dangers, Boeing put this stuff in a manual.

This was necessary as part of the pretense that a 737 is a 737 is a 737.

Mike "Mish" Shedlock

Comments (143)
No. 1-50
lol
lol

Boeing is the Chevy of the airline industry,except when your Chevy breaks down you pull off the shoulder of the highway and start walking,can't do that at 36,000 feet.....you're just dead.

Carlos_
Carlos_

Read that article the other day and %100 in agreement with it. In case you have not noticed the FAA and Boeing delayed grounding the Max until they had not other choice. Moreover, they are rushing as much as they can to "certify" the SW to get the Max back in the air. My guess is there will be another crash. This is what happens when $$$ is the determining factor.

JonSellers
JonSellers

MCAS - coming to your Autonomous Vehicle (Tesla, Uber) soon!

The 737 Max is a great lesson in government regulation. Among the FAA's many responsibilities is flight safety. And why don't we want to leave flight safety up to the Boeing's of the world? Well the 737 Max is a lesson. And the aircraft industry is special. It is incredibly capital and engineering talent intensive. And we are 100 years into finding and solving engineering problems. So the advantage of incumbents is so great that only governments (China, Japan) have the guts to try entry into the market.

So here's the interesting part to me. The FAA has to keep the overall industry as safe as possible and has generally done a decent job. This is important because without trust in the overall safety of the industry, the market collapses. If too many people think it is unsafe to fly, prices would have to rise above any market clearing level and the industry just goes bankrupt.

But Boeing itself is special. It is a national symbol, a major DOD contractor, employer and exporter. And it is the last of the great American airliner manufacturers. So the FAA has a fine balancing act of keeping Boeing solvent while keeping the system safe.

Obviously, the FAA failed. The system came down to an epic struggle between a CEO and Board fighting to "maximize shareholder value" in the short term Wall Street universe, and Washington bureaucrats receiving pot shots from Air force generals and corrupt politicians while still trying to get home by 5:00.

It all worked up until it didn't.

KidHorn
KidHorn

I don't blame the software developers. I'm sure they did what they were told to do. They didn't design the planes. It's not their fault the sensors are faulty or trying to patch hardware and/or design problems on a plane with software was and is a terrible idea.

Webej
Webej

Missing from this account is that in the design originally submitted to the FAA for testing and certification, the authority to adjust the trim was 0.6° but was later changed to 2.5° without resubmission. [1] This is certifiable and prosecutable fraud. [2] Needing 4× as much intervention as originally designed is itself a huge red flag.

magoomba
magoomba

All go to crusher. Start over.

thimk
thimk

another US legacy company bites the dust. so what are we going to export ? no one wants our frankenfood, no one will want our aviation products. well we still have the film industry.

Irondoor
Irondoor

When a pilot cannot disengage an autopilot or other such flight control augmentation system and fly the airplane manually, the potential for an uncontrolled crash escalates. Modern airplanes are the most complex systems in the world, and when passengers get on board, they rightly assume that the pilots are in total control of the aircraft. Apparently, not so. The controls are controlled by computer chips, servos and fly-by-wire. Perhaps they have become too expensive and too complicated and a method of simplifying the redundancy needs to be found.

I wonder if they tested these failures in the simulator?

Lumuno
Lumuno

Boeing must re-engineer the frame of the plane.. Make the plane higher and fit the engines comfortably under the wings. Software fixing remains a shortcut...and too risky!

abend237-04
abend237-04

It continues to make absolutely no sense to me for Boeing engineers not to have duplexed inputs to this critical system. There is a profound difference in actual system failure rates between one device with 99.99% uptime and two such devices in parallel: A single device gives you 53 minutes downtime per year, sounds pretty good unless it's just started on your flight, whereas two such devices acting in parallel gives 31 seconds per year downtime, a more than 99.4% reduction in system failure window. I've been in a lot of mtbf catfights over the years, and I can't imagine ever losing one this straight up, and mine never sent anyone home in a casket if I lost...just locked screens by the thousands, cleared parking lots and made you wish you were dead. I sooner believe an awshit happened somewhere in the MLC system than that a group of avionics experts sat around a table one day and agreed that single-point=of-failure was the smart way to go on this.

GuyD
GuyD

Big Strike #4: It would have been incredibly simple to build redundancy and fault tolerance into the MCAS software to turn it off (without a manual pilot process), think literally a few lines of code. The arrogance was in the approval of the system design specification not the coding itself.

SMF
SMF

You think this is a new problem? This type of automation problem goes back at least a decade, and it isn't even just a Boeing problem. This is in my opinion a little political as well. Here's a recent story about Airbus.

GOOFUS1t
GOOFUS1t

Sounds like a possible disgruntled writer. The 737Max has flown well over 40,000 flights over the past 2+ years with these two incidents and after the first one we learned that a pilot riding in the jump seat apparently overrode the flight crew and told them how to correct the issue which they did successfully. HMMM. Why didn't they know that and be did?

TommyTo
TommyTo

so if the plane is mechanically unstable by design and software is required to ensure system stability, it seems like there will be a lot of compensation going on which will cause undo wear and stress on components. i cant see myself getting on a plane that is mechanically unstable in its base design.

Hock
Hock

What to do with the remaining 737 Max? Boeing should give a huge price discount since it isn't a proper designed product. Stop taking new order for this plane. By price cutting enable the unfortunate airlines setting low ticket price so the passengers have at least some return for taking the risk of taking this plane.

Top-GUN
Top-GUN

Actually the software worked properly and as designed... The problem was the faulty input data from the Angle of Attack Indicator,,, a simplistic mechanical device.....

JoeSixpack
JoeSixpack

Read the whole story. Seems like click bait to me. MCAS is pretty easy to disable, 2 toggle switches. This is what the ride along pilot did on the lion air flight prior to the fatal flight. Why wasn't that info shared with the flight crew of the next flight? Oh, those switches are there before MCAS was ever in the plane. Yes understanding the plane is important. I agree that they should have considered more than a single AOA sensor. But don't use hindsight to throw Boeing under the bus.

Carl_R
Carl_R

Much of this article applies to the future, and to self-driving cars. Suppose you are in the car, and a look out the window tells you that the auto-pilot is making an error. Can you quickly take control back without having to read a manual? Oh, wait, there may not even be manual controls, or a pilot.

Or, we can take the reverse view. Why aren't planes self-flying? Should they even have pilots? Perhaps a self-flying plane would be easier than a self driving car as there is no traffic to deal with, no erratic drivers prone to make unpredictable decisions on the spur of the moment.

GranVio
GranVio

When plane manufacturer do their own self-certification with FAA consent, disasters occur inevitably

GranVio
GranVio

Incompetence Boeing & Complacency FAA led to lost of innocent lives at the expense of profitability and arrogance

rwthomas1
rwthomas1

I'm sorry, but Mr. Travis is a fool with an axe to grind. Or he's getting a nice check from Airbus. I too am a pilot. I have friends that fly for the majors, and they specifically fly the MAX. Any uncommanded pitch trim is dealt with the same way, you simply switch off the electric trim. Two switches right below the throttles. Doesn't matter if the uncommanded change in pitch trim is MCAS, or a runaway pitch trim motor, the result is exactly the same. Turn the system off. The aircraft can be flown safely, and easily by hand, using the manual trim wheel. This is basic pilot skill 101. Everyone is taught pitch&power the first day they are in an airplane. MCAS was designed to deal with unexpected pitch up due to the new forward position of the engines. If Boeing is guilty of anything it's producing faulty sensors. Why anyone would listen to some tool with an axe to grind is beyond me. Go find a MAX pilot and ask them. I know two, and the info I have is straight from them. Not filtered through the talking heads of the media.

Potsit
Potsit

Well ..who wants to take a plane 10,000 ft high that is proved to have so many issues.. and actually killed 350 people ..only idiot..

Grumblenose
Grumblenose

I don't want to fly in a 737 Max, but how do I ensure that I don't have to?

PaulJS
PaulJS

Able company behaving with negligent morality.

Shaner1
Shaner1

I will still fly MAX 8 once this aircraft gets back into the air

Six000mileyear
Six000mileyear

The SYSTEMS engineers are at fault. They are the ones who model the flight dynamics and flow requirements down to mechanical, software, and electrical engineers.

LuthfanP22
LuthfanP22

at time like this.. i missed my flight simulator teacher, Rod Machado and how he told me how to recover a 737 stalling plane. thanks Rod.

Willywonker761
Willywonker761

What a brilliant article. Quite well balanced and it explained things I didn't understand about what happened and how the plane was made and operates in flight. I'm a software developer so it was nice to understand how things work.

There were design issues I think from many different engineering, financial, and managerial backgrounds you can't just blame one discipline.

I'm very unhappy about the use of software and automation in planes, especially as a modification to an old plane. But looks like it could be cars next!!!

Daves21
Daves21

Nobody seems to have noticed that the airlines flying the most Max8 aircraft have had no crashes, for a person claiming to be a pilot the author doesn't mention the situations that the crashes had in common. I do believe Boeing should have been prohibited from passing the Max aircraft off as common type rated aircraft, that would have skewed economics but may have saved lives. That's not a certainty because the two crashes were in airlines with low proficiency crews, anyone afraid to fly a Max 8 or 9 aircraft should look at how many people die on American highway's annually.

FlashLumiere
FlashLumiere

An airline pilot and plane mechanic adds some explanations about the MCAS system in his videos. He said that the Ethiopian airline plane was doing 500 knots and that it would have been very difficult to trim the plane manually at that speed. please see

J1010
J1010

Boeing should just swallow their pride and correct the flaws in the aerodynamic flaws in the airframe. This simply means that even those claiming safe operation, the airframe experiences unnecessarily high stresses under normal operational conditions. Once this is not corrected, we shall begin to see issues of early fatigue a few years down the road leading to similar disasters. Accept it's a new plane, give it a new name and correct the dynamic stability issues but not with just software.

Scott553
Scott553

Good article and points to the baseline truth, Boeing didn't want to break the chain of keeping it a 737. If they did then they couldn't continue sales of a "new" model to their steady customers as the same type. Creating a new model causes new type ratings, sperate fleets, instructors, examiners, pay scales, etc. All things the steady customer doesn't want. Keep it looking the same to get it past certification and then you can sell lots of them and make your shareholders and wall street happy!

Hifly
Hifly

Why is it nobody is saying anything about Boeing taking the counter weight out of the tail section which made the center of gravity change 10 feet forward of the engine intakes at take off. With the engines already set well forward of the wings, at a stall even at altitude it would be almost impossible to recover. This is why in the old 737 center of gravity was center of wing at take off and could recover from a stall.

Leoxes
Leoxes

I agree to your conclusion, the strikes of failures (2&3) but not the argument. Many crash occurred when no visibility of the outside is possible, thus the instrument flying skills needed by pilots. And there are more planes nowadays that's inherently unstable and requires help to stabilise it to fly, most famously in military planes F117 and the B2. I doubt the list will decrease over time with push for economy in fuel and the plane and training etc. Increasing year on year. So, an aerodynamically unstable plane doesn't means it's unflyable, just need to be better designed to make it safer. And agree Boeing made an epic fail on this. The hard to override is terrible, insane decision, the one sensor reliance is simply ignoring all those crashes with blocked peto tubes, icing sensors history. Utterly disappointing on their part.

Hifly
Hifly

You hit it right on Leoxes

mark0f0
mark0f0

@Hifly additional tail weight would just make the situation even worse. The problem is that the aircraft tends to pitch up, potentially going into a stall. Not pitch down, in which case the tail weight would be required to balance things out.

The KC-135R (re-engined KC-135 with CFM56 engines and equipped with an APU on the aft main deck to start the engines as cartridge starters are not possible on the CFM56 for alert ops) has a permanent restriction that 3000 pounds of fuel must be carried and not offloaded in the forward fuel tanks, ie: the fuel is unusable. Due to the fact that the heavier CFM56's and their pylons mount them considerably more forward than the engines the plane was originally configured with.

Oldschoolmx
Oldschoolmx

Isn't it ironic that Boeing actually promoted on YouTube their inovative way ti extend the main gear height to give the airframe a higher stance for takeoff/landing by mechanically extending the oleo struts during these phases of flight and then compressing the height issue in order to fit the gear up into the wheel well since they can't relocate the pivot point on the wing without raising flags with the FAA and creating a "new" aircraft, type. I think the 737 airframe has reached its limitations for expansion and Boeing needs to revisit the drawing board. This is my observation from fixing 737's for18+ years....

Analyst78
Analyst78

While I agree that Boeing should accept much of the blame in your argument, let's not forget that the FAA (THE regulator for this industry) allowed all of this to occur on their watch. The same regulator who will not allow private pilots to earn income from transporting people and forces all of us to fly on one of a few conglomerates also didn't care one iota about our safety. Sure, none of the US piloted Max's have crashed, yet, but regardless of that this aircraft is inherently unsafe to fly. A regulator is supposed to care about safety and soundness for their industry not the profits of a single US manufacturer. All of this is indicative of the ongoing corruption in the Federal government which only serves it's corporate lobbyist masters.

leicestersq
leicestersq

I see a few people in the comments are blaming the pilots. I dont see it that way. All that matters is did the aircraft crash or not? If you are trying to sell an aircraft like this, high volume, to be sold all over the world, it needs to be stable and simple to use. Evidence suggests that it is neither.

I dont see an easy way out for Boeing here. A software fix is hugely risky. If another plane were to go down after such a fix, it could be the end of Boeing, who could trust them?

The other alternative is to redesign the plane. It looks to me as if a redesign to accommodate bigger engines will make the plane's characteristics very different to the current 737. Sometimes though, you have to bite the bullet and do the right thing. John Harrison changed his design philosophy and went from H3 to H4, a decision that changed the world. I think Boeing need to take a deep breath and consider a big change of their own.

Truedare
Truedare

I completely agree with the article. Only Boeing management will disagree. No software fixes required. Total hardware change required from blueprint stage.

Flip D
Flip D

I'm sure someone thought to make the struts @ a foot longer. Naa too complicated, software is easier. BTW I'm Comm Pilot, A&P, FE Turbo Jet, 5630 hrs tt. Not a newb.

YvesJ
YvesJ

This pilot says: your analysis is right on the money. 737MAX is an aerodynamically flawed airplane that would kill without MCAS. Pilot "punching it" or some particular turbulence condition can cause a stall that might go unnoticed. When autopilot is turned on the pilots relax somewhat and might not catch a stall problem in time. Now as we have seen, in specific circumstances, MCAS will kill too. Good luck to those who fly Southwest as they are a 737 only outfit whose CEO just doubled down on the 737, gambling with his passengers lives. I won't join them.

Graystokes
Graystokes

No expert on this but would this aircraft glide if it ran out of fuel or lost engines due to a bird strike or volcanic ash as a lot have proved they can

Old News
Old News

Mish, you do your readers a disservice. What Gregory Travis wrote was an opinion or essay and NOT a report. I read his entire article over a week before you picked it up, and I think "scathing" is a bit strong as well. I would encourage anyone who gets this far to read the original work rather thin this review. Mr. Travis gives a reasonable explanation of SOME of the things that probably went wrong inside Boeing specific to software ment to improve questionable but understandable poor decisions, things that may have lead to the two crashes in question. It is an enlightening and well written read. Please go read the original and not this hack review.

Sean 1981
Sean 1981

My name is Sean Frayling from England.   Following the news on the Eithiopian airlines Boeing 737 MAX 8 plane crash, I like to put a message across to not just Boeing, but any other aircraft Manufacture such as Airbus.   Although it is not confirmed, I am led to believe in a problem with a new feature on the 737 max series. (ANTI STALL SYSTEM).   I will start from when the first commercial jet airliners took to the skies. The Comet was grounded for a period of time due to several crash’s unexplained. Later, the Comets were back in service with unanswered questions. It took another accident for investigator’s to discover a fuselage problem and consider the comet to be unsafe to fly.   At the time of Comet dominating the skies, and falling from the skies, Boeing was already in production. It was too late for Comet to redeem themselves financially, among other reasons.   Since Boeing started dominating the skies, there have still been a lot of accidents over the years, which have been investigated, and problems have been solved. Not just Boeing, but also Commercial Douglas planes. I could go on forever about aviation history in terms of accidents.   My point is, when there is a problem causing planes to fall, it seems that it takes a few accidents to consider that a plane maybe unsafe to fly.   The new Boeing 737 MAX series is no acception.   If we look at flight safety history, there is a pattern of accidents on particular aircraft’s. Each accident leads to flight safety improvement. Over the years, planes have been getting safer and safer to fly with modern technology and human knowledge. But there has to be a point when planes do not need new technology or improvements in terms of flight safety for passengers and crew. Only keep planes well maintained. I believe that time has come.   The year 2017 is recorded as the safest year to fly with no major accident. Year 2018 should’nt be any different. The new Boeing 737 MAX series Lion airlines changed that theory in August, and again now just recently with Eithiopian airlines.  This would suggest that planes are now as they should be, and that they only need regular maintenance. Introducing new technology or new features pose a life threatening risk in the sky, as we have little knowledge on new technology as we are still learning about new technology.   Boeing are confident to say that the 737 MAX series is still safe to fly, yet 2 new planes fall from the sky allegedly caused by the same problem. A new anti stall system. This new feature is proving to fail as it forces the plane’s nose down during take off.

This begs the question, how many planes need to crash before the planes are considered unsafe to fly? How many people have to die before the planes are considered unsafe to fly?   One crash is one too many. It’s like Boeing are trying to fix something that is not broken. If there have not been any accidents in the past 2 years, why introduce a new plane with new technology that could potentially go wrong? As in this case has gone wrong.   I believe it’s now time to stop trying to improve flight’s, and just keep the current fleet maintained without the MAX series.

Although Boeing promise to do a software upgrade on the max series, even after testing, its not guaranteed it will work for long during flights.

A good example in the early ninetys prooved this with a rudder problem bringing 2 planes down and almost a third plane. Although the rudder was tested after the 2 accidents, it still failed on a third plane and the rudder was able to work in reverse by itself. Since the rudder has been re -designed, there has been no problems. This is just 1 example.   I follow these stories very closely, and very happy to see flight safety at its best. Disappointed to see the MAX series ruin this reputation.   Its understood that the MAX series is grounded worldwide, for understandable reasons.   The question now is, can Boeing afford to risk hundreds of live’s with a new feature? My answer is no. Boeing have a very good fleet now with very good reputation. We do not need the MAX series.

Planes do not need an anti stall system, as pilots have a stall preceder to follow safely if a stall accurs.

Its possible that the anti stall system could be conflicting with the planes performance during take off with the anti stall system thinking the plane is in a stall because the plane is low as it takes off.   Personally, on my future flight’s, I would refuse to board if I see a MAX series on the tarmac, and that I would request a flight change at the airport, on the grounds of the MAX series reputation.

Joshua rowe
Joshua rowe

If i recall correctly, Airbus had a similar problem with its 300-600 when the addition of more powerful engines (without an increase in size of tail plane) caused unexpected pitch-up angles when having to execute a 'go-around' - in auto-pilot mode. This panicked pilots and caused them to push the nose down which was then countered by the auto-pilot. The result was a stall and, at least, 2 cashes

Airexpert
Airexpert

As an industry expert, I have flown the 737 max as a line captain and it was my 12 th type rating. This being said, i can tell you that the MCAS is the tip of the iceberg, this airplane is majorly flawed not only aerodynamically but also technically.

Never before have I encountered such strange behaviour from an airliner.

Two thing jump to me.

  1. AOA don’t fail, we have a series of failure of this part, it is the beginning of the problem.

  2. Pilots are now younger and more inexperienced, a bad stall indication system will only exacerbate the situation. Adding a light or more information to digest will only delay the response.

  3. The automation is very very weak compare to other Boeing products and especially to its arch rival Airbus.

I have flown the Boeing 767 which was desing in theory 30 years passed and it is more advanced that the 737 max. Why? Simply because the 737 max is actually an older design and has shown the limits of what this fuselage could bring. It’s like having an IPhone 10 that you have to plug in a phone jack to get internet.

Besides, I have seen autopilot kicking off for no reason and weird roll behaviour in some instances.

I asked to be removed from flying the 737 max ever again. I don’t trust this airplane and I have 17000 hours as a line Captain and have been an instructor for close to half this time. Why should the public trust the airplane? I don’t.

Jerrysm
Jerrysm

My understanding and view are both very simple. Boeing built a plane that has aerodynamic problems due to the position of its engines. Instead of redesigning a completely new plane that has the correct height to accommodate the new bigger engines, they opted to design a software to fix the stalling problem that is created by the engine position problem. Problem which should not have been approved by the FAA.

Boeing should cut it losses short by going back to the drawing board.

Nick84
Nick84

One more 737 MAX crash and Boeing is toast, brought down by MBA-type suits with polished speeches, zero understanding of engineering and focused on "maximizing shareholder value" nonsense.
The quality lapses at Boeing (also on other models, such as 787) are shocking. I lost confidence in this company.