The Trials and Tribulations of the 737 MAX

this episode. So the week I'm recording this, which is the very end of October, actually technically today is November one. The CEO of Boeing just appeared before Congress to answer questions about the tragedies involving two seven thirty seven Max aircraft crashes. Politicians asked some very pointed questions to find out when people at Boeing became aware of problems with the aircraft and how much they knew, as well as other details. So in this episode, I want to explore

exactly what went wrong and why. And while you could summarize the story by saying a sensor and some software malfunctioned, that's not really a full understanding of exactly what went wrong and why it went wrong. So let's start with the seven thirty seven Max in general, and the seven thirty seven Max is history really only dates back to

July two thousand eleven. That's when Boeing learned that it's competitor, air Bus, had made a deal with American Airlines to sell two hundred A three twenty neo aircraft and the eight three twenty family of aircraft first debuted in nineteen eight six. They're intended to serve as short to medium

range aircraft. They are narrow body aircraft, which means they have a cabin that measures no more than thirteen ft or four meters wide, and they have a single aisle going down the length of the cabin with seats on either side. In other words, these aircraft sir the same function as something like the seven thirty seven does. So it might be a good idea to do a quick rundown on the different sizes of aircraft and what they're intended functions are, and to understand why we even have

these different sizes of aircraft. It helps to understand the history of the development of airports and airlines in general. I find that it could be easy to forget that the systems we have in place today evolved over time out of necessity. But I also know that's not the focus of our episodes, So we're gonna be super general. I'm not going to spend an enormous amount of time on this, So the Right Brothers, really, I'm not going

to spend a whole lot time on this. But they developed the first real airplane in the United States in the early twentieth century by n In the United States, the government had passed the Air Mail Act that gave the Postmaster General the authority to work with private airlines flying between certain routes the ability to carry mail. This was sort of laying the groundwork for the modern airline.

The government followed that up with the Air Commerce Act, which gave powers to the Secretary of Commerce to create the rules and regulations that would apply to commercial aircraft. That included requirements to license pilots, to certify specific aircraft as being safe for commercial operation, to establish air routes, and to create rules for air traffic. Now, many airlines

in this time were regional. They were operating between a handful of cities within a general area of the United States, but they gradually were able to grow to provide service to more airports further afield. This might require a certain number of hops between cities, and it created an incentive for aircraft and engine manufacturers to find ways to increase the flying range of aircraft to allow for more direct service options between distant cities. The US government wasn't done yet, though.

In ninety eight, Congress past the Civil Aeronautics Act, which in turn created these Civil Aeronautics Board or c a B. One of the board's responsibilities was to regulate airfare prices for passengers. Another was that it could assign specific routes to airlines, giving permission for them to operate flights between specific cities. The price regulation meant that airlines couldn't really compete against each other with battling with lower fares for

routes between the same cities. A ticket on one airline for a trip between let's say New York and Chicago would cost pretty much the same as a ticket on another airline because of this regulation. So that meant that these airlines had to differentiate themselves in service because price was going to be the same no matter where you were going. Right if you went on one air airline versus another you're gonna be paying the same amount, So why would you choose one over the other? Had to

be because of the service. Further, if the Board determined then airline was providing sub standard service along a specific route, then the board would allow other airlines to operate along that same route in order to create the competition needed

to improve service. So if the Board were to look at say t W A and say, your service between this city and that city has been reported as being substandard, We're now going to allow these three other airlines to compete in that space, the idea was that things would improve. In nineteen fifty eight, the US government established what we now call the Federal Aviation Agency or f a A,

which oversees airline safety operations. Twenty years later, in nineteen seventy eight, the economic climate had changed in the United States. Foreign airlines offering service to the US were not bound

by the price regulations of the Civil Aeronautics Board. American airline companies could not compete with the lower airfares posted by these foreign companies, and there was a growing resistance to regulations in general in the US, so Congress passed a deregulation Act than the Civil Aeronautics Board disbanded, The price regulations came to an end, and airlines in the United States could charge whatever they felt the market could

bear for any of their airfares. This also allowed new airlines to join the market, which had previously been dominated by just a few major carriers. The influx of competition was a boon to passengers as far as airfare price is concerned, but less so when it came to in flight experience. More on that in just a moment. But it also meant that some of the larger airline carriers were struggling to compete. They had grown very large, and they depended on a certain amount of revenue that happened

to have been guaranteed by the regulated prices. So when those regulations went away and smaller, more nimble companies began operating routes previously commanded by these giant companies, while the giants began to wobble a little bit. This was exacerbated by an economic recession in the nineteen nineties that saw a reduction in air travel, and some of the big airlines outright collapsed into bankruptcy, like t w A and

Pan American. So another recession in two thousand one, and then the terrorist attacks on nine eleven further hurt the airline industry, which would remain unprofitable for five more years. Now since then, you know, since two thousand six, airlines

have managed to turn things around for the most part. Now, the reason all of that was important is that it creates the foundation for us to understand why there are so many different types of aircraft out there, and why conditions and aircraft have changed over time, and this in turn informs us as to why Boeing made specific decisions.

So you may have seen images of air travel in the nineteen fifties or nineteen sixties when it looked like everyone was dressed in their Sunday best and they're enjoying a big, comfy seat with plan D of leg room, and they might even be chowing down on an impressive looking meal. It's a pretty dramatic contrast to what you find on a typical commercial jet today. So let's talk about the different types of aircraft classes and what there for and why things have changed. So you've got wide

body aircraft. These are the ones that are meant for long range routes, usually such as transatlantic or trans Pacific routes. They typically have two aisles running the length of the cabin, and the width of the cabin tends to range from sixteen to twenty feet or five to six meters. You can have up to ten or maybe even eleven seats arranged in a single row. In the economy class. They

really pack them in like sardines and some aircraft. That means that with the size of some of these aircraft, you can have configurations that can carry more than eight hundred passengers, which is mind blowing to me. Most of them are more like two fifty four passengers, but there are some configurations that have significantly more than that. The

original wide body aircraft were something like luxury vehicles. They were intended to provide a superior experience with more room per passenger than you would find on other types of aircraft, so they weren't all about packing as many people in as possible. But then once the industry underwent deregulation, folks that airlines began to figure out that there was another

tactic they could use. They could cram way more seats on those aircraft, actually reducing the space for the average traveler and maximizing the number of passengers that could fit on a single flight. After all, the airlines were no longer restricted to a regulated airfare price. They didn't have

to compete on the basis of service. They could compete by offering lower airfares, and they can make up the difference by putting more people on a single plane, so they could actually make more money per trip even by

offering lower airfares per customer. By doing the old stand by, you make it up in volume, and after balancing out the pros and cons of delivering a superior experience to the alternative of just going for the cold hard cash, most airlines went the cold hard cash route, and thus we started down the pathway of encountering aircraft with decreasing amounts of leg room, narrower seats, and other features that fuel stand up comedian routines. These huge aircraft are really expensive.

They also can't fit on all runways, and not every airport can accommodate them. They were used for routes where it made the most economic sense to use them, typically on those transcontinental or trans oceanic flights. These tend to be long range aircraft because they are more expensive to purchase, maintain, and operate. Airlines typically have fewer of them in their fleets, so they dedicate them to these long range routes. Enter

the narrow body aircraft. These became popular starting in the nineteen sixties, but they really took off pun intended after deregulation. They tend to be much less expensive to purchase, maintain,

and operate than their larger cousins. They can fit in more airports and more runways, and they played into an economic strategy that airlines used to compete against each other because there was one other thing you could do to use to your advantage besides the level of service or the price of the airfare, and that was the frequency of flights for specific routes. Now this really got going with deregulation and the emergence of new airlines. Now passengers

could have a lot more options. When they were booking a trip earlier, you might have a route that only had two or maybe three flights per day between two cities, so the passenger had to fit their schedule with the airline schedule. But with more routes approved and more narrow body aircraft in fleets, airlines had the chance to increase the frequency between certain cities that had demand that warranted it, and as you would imagine, most of the time, this

would involve cities that had regular traffic between them. You weren't suddenly going to see an enormous increase in flights to some city that was far out of the way of everything else. Because there's no demand between two cities, it makes no sense to operate hourly flights between them. But for some routes that's exactly what did make sense. So airlines began to compete by telling customers, hey, we operate enough flights to your destination that you don't have

to worry about conforming to our schedule. We've got a flight that fits your schedule. So this was the era in which we saw the narrow body mid range aircraft come into prominence, and that included the Boeing seven thirty seven. The original seven thirty seven was introduced by Bowing in nineteen sixty six. It was nicknamed a square airplane because the length of the aircraft was the same as the width of its wingspan. Both were approximately ninety three feet

or a little more than twenty eight meters. It's a twin jet engine aircraft and the original seven thirty seven had an engine mounted under each wing. This becomes an important element when we get to the design of the seven thirty seven Max. Now there are different versions of the seven thirty seven that have different dimensions. The original seven thirty seven one hundred innered service for the airline

luft Hanza, among others. United Airlines expressed interest in purchasing some seven thirty seven's, but that airline wanted a slightly longer version of the aircraft, so Boeing adjusted it and then created a version of the seven thirty seven called the seven thirty seven two hundred, and There are several others, including the recent seven thirties even Max Okay so aircraft, like the seven thirty seven from Boeing and the A three twenty from air Bus, served similar purposes to act

as a short or mid range aircraft capable of carrying around two passengers, which varies depending upon the aircraft's configuration. By two thousand six, Boeing had been relying upon the seven thirty seven design for forty years, when the company began to consider the possibility of an entirely new design to fill essentially the same function as the old, reliable

seven thirty seven. That decision was a huge one and would require a lot of steps, So Bowing kicked the idea down the road a few times, and then we get to two thousand eleven and American Airlines ordering the two hundred Airbus aircraft. It sent a signal to Boeing that delays we're going to cost the company big time.

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That's e x p R e S S vpn dot com slash tech stuff for three months free with a one year package. Visit express vpn dot com slash tech stuff to learn more. Now let's get back to the seven thirty seven Max Alright. I left off saying that Boeing concluded that developing an all new type of aircraft wasn't going to pun intended fly. As Airbus began to gain popularity among airlines and American airlines had as part of its plan and order for a re engined seven

thirty seven aircraft. Boeing would need to focus on that effort, and it abandoned the design of an entirely new aircraft. It finally said, Okay, it doesn't make sense for us to create a new aircraft from the ground up. Let's go back to the seven thirty seven and make some adjustments. This also brought with it a few other potential benefits. Developing a new aircraft is time consuming and incredibly expensive.

Not only is the development process itself expensive, then there's the certification phase, in which the aircraft must pass requirements set by the various aviation authorities around the world in order to be allowed to operate as a commercial aircraft. And then there's the training phase. Pilots have to train on the new aircraft to learn its systems and how it flies. Not all aircraft behave the same up in the air, and that means it's a really big deal

to invest in an all new type of aircraft. It's asking for a lot of resources, both from the manufacturing company and the various airlines out there. Updating and existing design is far less daunting. The basic bones for the aircraft are already there, and if the changes are within certain parameters, you can get through regulations pretty easily. After all, the base aircraft has already been through that process and

had been approved. Likewise, if the changes aren't dramatic, pilots might be able to fly those planes without any real additional training or having to go into any flight simulators, because the aircraft, at least in theory, is going to perform within the basic parameters of its predecessors. So there are a lot of strong business cases for sticking with

a previously engineered design. Boeing's decision to stick with the seven thirty seven was both more economical and, due to the agreement it had reached with American Airlines, pretty much necessary. One of the big goals Boeing had was to improve fuel efficiency so that the seven thirty seven Max could fly the same distance as older seven thirty seven's while

burning less fuel. That would also mean the seven thirty seven Max could potentially have an increased range of flight compared to earlier seven thirty seven's, and you could argue that ultimately it was this push that would lead to the tragedies of the two seven thirty seven Max crashes that would ground the global fleet of seven thirty seven

Max aircraft. It's a sort of cascade effect where one decision, that being to re engine the seven seven would lead to other decisions that ultimately set the stage for catastrophe. And by the way, this is all very easy for me to say in hindsight, I'm not trying to suggest that I would have spotted the potential for disaster before it happened. It's only because it happened that we're able to go back and analyze this and see where the mistakes were made. But at the time it was not

necessarily that clear, at least not outside of Boeing. Boeing chose for this new version of the seven thirty seven some engines from a company called CFL. CFM is actually a joint venture between g E Aviation and Saffron Aircraft Engines.

So in two thousand eight, CFM introduced a class of engines they called the Leading Edge Aviation Propulsion Class or LEAP l E a P. Boeing opted for the Leap one B model of engines, which has a thrust range between twenty three thousand and twenty eight thousand pounds of thrust or between one hundred and one killing Newton's of thrust and Newton is the amount of force required to accelerate an object with a mass of one kilogram and

an acceleration of one second per second. CFM chose several engineering advancements that contributed to better fuel efficiency and its leap engines compared to older aircraft engines. That includes carbon fiber composite components that are stronger than earlier materials at a fraction of the weight, so while the engines are big larger than previous seventh D seven engines, they don't

necessarily weigh as much as those older engines do. CFM also used additive manufacturing, more commonly called three D printing to produce those components. The leap engines also pre mix fuel and air together before the mixture hits the nozzles that enter the fuel into the combustion chamber, So older engines would inject essentially amissed a fuel into the combustion chamber and the mixing of the fuel and the air

happened inside the chamber itself. But according to CFM, that meant lower fuel efficiency and greater emissions, So they say that this new method cuts down on emissions and you burn more of the fuel. The engines would give Boeing the boost and efficiency needed to meet American airlines requirements. In August two thousand eleven, Bowing officially announced the development of this new version of the seven thirty seven, and the company began to market the aircraft to various airlines.

By December two thousand eleven, Boeing found a customer in the form of Southwest Airlines, which put in an order for one fifty of the aircraft. Aircraft that were in the earliest stages of development, mind you. From two thousand eleven to two thousand fifteen, Boeing worked on the design and production of the seven thirty seven Max. And here's where we see some other decisions that would ultimately contribute

to the problems we saw when it entered service. The new engines were larger than the previous seven thirty seven engines, as I mentioned earlier, and traditionally those earlier seven thirty seven engines would be mounted under the seven thirty seven's wings, but these new engines were too big to do that and still allow for adequate ground clearance between the bottom of the engine and the ground itself, So that meant the engineers had to figure out where to put these

engines on the body of a seven thirty seven, and ultimately they decided to move the engines forward along the body, ahead of the wings, and their position in such a way so that the exhaust of the engines is directed underneath the wings, which makes sense. You wouldn't want it to go right up against the wings you melt your own wings off. And also the way that their position now means that the bottom of the engine has sufficient

ground clearance. But moving the engines forward had another consequence. It changed how the aircraft moved in flight. Moving the engines forward meant that in flight, the seven thirty seven Max has a slight tendency to tilt its pitch upward, in other words, to tilt its nose up towards the sky in a climb. That can be a problem for lots of reasons, but a big one is on takeoff.

I mean, obviously you're climbing in takeoff, and in that phase, pilot's guide a plane into a climb to reach cruising altitude. So you don't want a plane to overcompensate and tilt further back than the plan to climb for lots of reasons, but a big one is that it can cause the engines to stall out. So for a jet engine to work, you have to have air flow going through that jet engine in sufficient quantities, so it has to be moving

there in a sufficient speed. Essentially, I covered this in recent episodes, so I'm just going to do a quick overview. In a jet engine, incoming air hits fan blades that compress that incoming air, which then either flows in or

around a combustion chamber where the engine ignites fuel. The resulting hot gases in the combustion chamber expand and then force their way out of the chamber through an exhaust nozzle in the back of the chamber, and as they escape they hit rotors on the rear side of the engine, and the rotors connect through a shaft to the fan

blades that are in the front of the engine. So as that exhaust is coming out the back of the engine, it hits the rotors, and the rotors turn because of that rapidly escaping gas, and because that's connected by a shaft to the blades in the front, it turns. The fan blades in the front of the engine, and the whole thing perpetuates itself because of this continuous burn inside the combustion chamber. But for this to work, you have to have a sufficient amount of air flowing into the

engine in the first place. This is also why it's necessary to jump start a jet engine on the ground. They forced compressed air through the jet engine in order to get it going, because you cannot get it started any other way. Now, if the plane were to tilt too far in an incline when it's climbing up into the sky, the angle of the engine compared to the airflow would be such that you wouldn't get enough air to go through the engine for it to maintain operation,

and that's why it would stall out. You would have a lack of air to keep that whole process going. Installed engines would clearly be a disaster. Once Boeing engineers recognize the tendency for the seven thirty seven Max designed to go into this unprompted tilt, they had to how to address that problem, and their solution was a combination

of hardware and software. On the hardware side, they relied upon sensors that would automatically analyze the difference between the airplane's attitude in the air and the angle of attack. So the angle of attack describes the angle of a plane's wing with respect to airflow. Angle of attack is a big component of lift, that's the force that keeps aircraft in the air. The other major hardware component is the aircraft's horizontal tail, which can tilt to change the

plane's pitch. By altering the orientation of this horizontal tail, it could act as kind of like a rudder, except a rudder for the horizontal access, not the vertical, and the effect is that it could force the nose of the plane back downward in one of these climbs, so, in other words, it could affect the pitch of the airplane.

The software overseeing the whole operation of this, which would monitor the data coming in from the sensors and then send appropriate commands to the tail, is called the Maneuvering Characteristics Augmentation System or m CASTS. So if you've been following the story of the seven thirty seven Max, you've

likely heard the term m CAST thrown around now. In theory, m casts would operate in the background and make the seven thirty seven Max perform as if it were any other type of seven thirty seven aircraft, so it was

designed to override pilot controls. But this also meant that if the system were to erroneously detect that the aircraft were in too steep a climb, the tail flap or the horizontal tail rather could force the plane into a dive and the pilots would be struggling to pull out of it, and they'd have to figure out how to do that, and that would also mean knowing how to disarm the system. Okay, so Boeing was pushing hard to get the seven thirty seven Max ready to compete with

the Airbus A three twenty neo aircraft. The f a A helped expedite things. In two thousand fifteen, according to the Seattle Times, the f a A managers put pressure on the agency's safety engineers, telling them to delegate the assessment process to Boeing's own staff. This, by the way, it doesn't seem like it's completely unusual, but it did

come as something of a surprise to me. I did not know that's how things worked, because, in other words, what that means is the agency and charge of overseeing safety passed that job along to a company that produced the very thing the FAA was meant to oversee. And that might sound like it might not be the best idea.

I happen to think it was a pretty bad idea now, granted, as we are now seeing, a failure on the part of a company to be completely honest and rigorous with its safety assessment process can result in terrible tragedies for passengers as well as real hardships for the company itself. So companies like Boeing have a very strong incentive to police themselves care late. However, it sounds like that's maybe

not what happened with Boeing's self assessment. Again. According to the Seattle Times, the safety analysis understated how far the im cast software could force the horizontal tail to move in an effort to stabilize the planes pitch. The Times reported that in reality, the software was able to make the tail move more than four times further than what the report indicated, meaning a much more dramatic change in

pitch than what Boeing was claiming in the report. And Boeing's response to this was that initially Imcast would be able to move the horizontal tail at an angle of point six degrees. It turned out it was more like two point five degrees, and Boeing said, well, it was only upon further study that we realized in order to pull out of a disastrous climb, you would need a greater movement than just point six degrees, which is why we increased it. But at that point we had already

written the report. Seems to me like there might have been an addendum that needed to be added there, but what am I to say? So the report did not address how mcasts would reset after a pilot's response and

would go into another dive despite repeated manual attempts to recover. So, in other words, if a pilot were to respond to this unplanned dive and pull back, you know, activate the control and pull back on it, then it would stop the system temporarily, but it would just reset and start the cycle over again, and it might get more dramatic each time. The the amount of of of tilt that the horizontal tail would take, and thus the amount of dive the plane would go into, would get greater each time.

The criticism is that the safety measure had no self correcting process that would discontinue the diving efforts after manual intervention. It would just keep going into a dive. So the argument is that there should have been a system in place where if a pilot intervenes, it deactivates this process that was not in place. The Times criticized that the assessment stated that if the system were to fail, it would merit a hazardous danger rather than a catastrophic one.

These have real meanings in safety assessments. Hazardous means that the outcome could result in injury or death to a small number of passengers in a plane. Catastrophic is essentially a designation stating that such a failure would result in the complete loss of the plane and everyone on board. So Boeing was saying that a failure of the system would merit the hazardous level, not the catastrophic level. So, in other words, the criticism is that the report was

downplaying the actual outcome of a system failure. One other major problem is that Boeing neglected to include information about m casts in its operation manuals for the seven thirty seven Max. Pilots didn't know about it, airlines didn't know about it. It wasn't until after the first tragedy that this would be amended. When we come back, I'll talk about that accident and the following events. But first, let's

take another quick break. Perhaps because the f a A delegated the safety assessment duties to Boeing, Perhaps because the seven thirty seven Max was a variant on a tried and true aircraft design that had been an operation for at that point fifty years. Perhaps because simulations failed to create the sort of scenarios that we would unfortunately see unfold in the actual operation of the aircraft. The seven

thirty seven Max past certification without much hullabaloo. Then, to be fair, it seems in more investigations that some of those simulations actually did show some problems, but Boeing didn't really address that at the time. There was also no need to train flight crews on how to operate the seven thirty seven Max, because in theory it behaves so much like other seven thirty seven's, particularly the seven thirty seven in G, which was the immediate predecessor of the Max.

Pilots reported that they essentially had to complete a one hour course on a tablet and not even spend any time in a simulator before they would be certified to fly a seven thirty seven Max. However, you want to lay it out. The end of the matter is that the seven thirty seven Max received its certification and Boeing began to deliver the aircraft to customers. One of those customers was Melindo Air, a carrier based out of Malaysia and a subsidiary of a larger airline called Lion Air.

On October twenty ninth, two thousand eighteen, Lion Air flight j T six ten, which was a seven thirty seven Max eight, crashed just thirteen minutes after takeoff from Indonesia. The plane crashed into the sea off Jakarta. All one eighty nine people on board died as a result of that crash. Among them were twenty Indonesian government officials. The

plane had been in use for about two months. A pilot had reported a problem with the aircraft right away, requesting a return to the airport before they lost control of the aircraft. The CEO of Lion Air at the time reported that a different pilot had reported the same plane for a quote technical issue end quote earlier on that week, but that the aircraft had been cleared to

fly the following day. An investigation following the crash indicated that one of the angle of attack sensors had malfunctioned on the Lion Air flight, and it had mistakenly indicated a dangerous change in pitch and an oncoming engine stall, and none of those conditions were actually existing at the time. But the im CAST software and system went into action, forcing the horizontal tail to move the the the nose of the plane downward and put it into a dive.

The pilot was unable to counteract that, and the plane crashed as a result. Making matters worse was the fact that Boeing had not indicated the im cast was even a thing. The pilots had no way of knowing what it was that was causing the plane's nose to dive or how they were supposed to stop it. On November six, two thousand eighteen, Boeing issued a report revealing im CAST to pilots and airlines for the first time. The report also gave instructions to pilots on how to override in

cast in the event of a failure. Not At this point, it wasn't yet certain that im casts was at fault, but the signs were starting to point that way. In the meantime, Boeing continued to receive orders for the seven thirties seven Max from various airlines and was still in full manufacturing mode. One thing Bowing did that later drew an enormous amount of criticism was to place some responsibility on the pilots themselves, stating that they should have known

to cut off the switches to the planes stabilizers. But analysts who looked at the recovered flight data for the Lion Air disaster said that what the pilots had experienced didn't look like a stabilizer runaway scenario in which an element like the seven thirty seven Max's horizontal tail would

make a continuous, uncommanded movement. The Lion Air flight data showed that the tail movement was not a continuous motion, and then the pilots were able to use the controls to pull up several times before the plane became uncontrollable. The analysts contradicted Boeing, saying that it wouldn't have seemed obvious to cut off the stabilizer controls based on what was happening then. On March tenth, two thousand, nineteen, and Ethiopian Airlines flight from Addis Ababa to Nairobi crashed not

long after takeoff. Air traffic control lost contact with the plane just six minutes after it left the runway. All one fifty seven people aboard that plane died from the crash. Early analysis suggested that once again, this was a failure of m CAST. Further investigation showed that the crew attempted to follow Boeing's instructions to correct for the failure, to no effect. One day after the crash in Ethiopia, China, and Indonesia, authorities issued orders that all seven thirty seven

Max aircraft operating in those countries were to be grounded. Now, at that point, it was not yet known that m CAST was definitely at fault for that second crash. The day after that, on March twelve, two thousand nineteen, Canada, the EU, and India also ordered all seven thirty seven Max aircraft grounded. The f a A in the United States would follow suit one day later, on March thirteenth,

two thousand nineteen. At that point, investigators were seeing signs that IMCAST did play a part in the second crash. The U s Department of Justice began a sweeping investigation into the matter, and particularly into the process of the jets certification. How could it pass certification if it had

this incredible flaw. That investigation has uncovered other concerning details about the issue, including the revelation that a Boeing pilot had brought concerns about the flight system of the seven thirty seven Max to the attention of Boeing officials back

in two six. Previously, Boeing management had maintained that they had no idea that the flight control system could cause a catastrophe, but pilot Mark Fortner said that while flying simulations that incorporated m CAST, he had encountered cases where the flight management system was, in his words, quote running

rampant end quote. The revelation of this pilot's warnings came a little more than a week before Boeing CEO Dennis Muhlenberg and John Hamilton's Boeing's lead engineer, were to appear before the United States Senate and the United States House

of Representatives and back to back hearings. During those hearings, officials accused Boeing of purposefully downplaying safety issues and concealing potential problems in an effort to achieve certification as quickly as possible and thus start selling planes as quickly as possible. Those officials are also concerned about the f a a's practice to deputize the very companies it is supposed to

certify in the safety assessment process. Now that's not to say that the US government is now advocating for sweeping changes in certification or or even going to come down hard on Boeing, because it's not as simple as that. At issue isn't just the fate of Boeing, which is

an enormous employer in the United States. That also means that there's a whole lot of folks who are potentially voters who could be affected by any massive problems that Boeing faces, and politicians are a little squeamish about doing things that could potentially upset voters. There are airlines that have aircraft they can't use. They're dealing with this problem

to they're looking at lost revenue. And there are all these companies that supply bowing with components like GE, you know, one of the companies responsible for the seven thirty seven max engines. GE has had its own share of problems recently. You can listen to my episodes about General Electric that published not too long ago to learn more about those. Because the seven thirty seven max is effectively on hold. It could potentially cost companies like Ge and others billions

of dollars. Boeing, for its part, has made major changes to m CAST. A big one was that moving forward in CAST will take into account both angle of attacks sensor before changing the horizontal tails orientation. It would no longer accept just one stream of data as being enough

to change the plane's pitch. One of the other major criticisms directed at Boeing from a design level is that the MCAST sensor was a single point of failure with no redundancy, and when coupled with Boeing's self assessment that a failure just represented a hazardous outcome but not a catastrophic one, create a false sense of security. Another big change is limiting how much the tail will move like

I said. The original safety assessment said the tail would only move point six degrees, but in practice it was more like two point five degrees at maximum. Boeing has also stated that it is going to limit the system to activating for a single cycle, as opposed to the reset repeat process that was seen in both Lion Air and the Ethiopian Airline crashes. Then there's the long tail stuff that Boeing is going to have to deal with,

stuff like trust and perception. While Bowing has made efforts to address the problems in its seven thirty seven Max flight systems, the company's credibility has taken a hit, as has the perception of the f a A. There's still lawsuits against Boeing that are making their way through the legal system that are a direct result of the seven thirty seven Max disasters, and Boeing still has hopes that the aviation agencies around the world will lift the grounding

of the seven thirty seven Max aircraft before the end of twenty nineteen or in early twenty twenty. Meanwhile, the company has another headache to deal with. In October two thousand nineteen, reports came out that aircraft operators had discovered cracks on the seven thirty seven in G aircraft, or at least some of them now. As I mentioned earlier, the seven thirty seven in G is a predecessor to the seven thirty seven Max. It's been in service for

several years. It doesn't have the m CAST software or the engine placement of the Max, and it remained in operation with any problems. But in early October two thousand, nineteen, U S officials ordered an inspection of seven thirty seven in G planes that had completed more than thirty thousand cycles, that is, more than thirty thousand takeoffs and landings. And the whole point was to look at the section of the plane where the wing attaches to the body of

the plane. It's a part of the plane that is called and I swear I'm not making this up the pickle fork. Several airlines outside of the United States also began to inspect their seven thirty seven in G s, even those that had not yet completed thirty thousand cycles, and reportedly some of those aircraft have had cracks appearing in the pickle fork as well. Boeing stated that out of the one thousand, seven thirty seven in G s that had been inspected so far, inspectors that only indicated

that five percent of them have had cracks. Still, it's another indicator that things are not going so great for Boeing right now. We'll have to wait and see how this all plays out, whether or not the seven thirty seven Max will return to service, whether or not people will trust it. You've had a lot of us politicians already saying that they would not get on a seven thirty seven max to take a trip based on what

they've seen. So there may be an inherent trust that ends up being an enormous barrier to the seven thirty seven max, even if the technology is proven to be safe. So that's a huge issue. Once you've eroded trust, it's very hard to rebuild. So we'll have to wait see how that turns out. I am very curious to see it myself. I've definitely been interested in this subject. I fly fairly frequently, and knowing about this is something that

I think is important. Um, it's also something that fills me with anxiety if I'm being perfectly honest, but I'd rather know than not know. Anyway, that wraps up this episode of tech Stuff. If you guys have suggestions for future episodes, send me an email. The edge says tech stuff at how stuff works dot com, or you can

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