2 The Biggest Lie about MCAS

Most articles on the two Boeing 737 Max plane crashes have only scratched the surface of what happened or why these two planes crashed in nearly identical death dives. The corporate media would have you believe that some out of control computer programmer at Boeing wrote a bad software program called MCAS. This software programmer was so dumb that he or she failed to anticipate that the program might get a bad reading from a defective Angle of Attack (AOA) sensor located at the front of the 737 Max (as we will explain below, these sensors have been giving bad readings for years and everyone other then the public knew about it).

But back to the “simple” story told by the corporate media. MCAS was intended to keep the nose of the plane from going so high that it would stall. But instead of MCAS pushing the nose back down into a safe, level position, MCAS was badly written by our villain - the crazy computer programmer. MCAS went haywire and took over control of both planes – forcing both of them into a steep dive – causing them to crash into either the ocean or the desert. End of story.

According to this story, all Boeing needs to do is to have wiser computer programmers make the MCAS program less aggressive with a software patch. Boeing will then explain to pilots how MCAS works (especially how to turn MCAS off if it goes berserk again). Boeing will also use two of these unreliable sensors instead of only one - and the problem will be solved.

To reassure the public that the 737 Max is safe, the FAA will require Boeing and their highly experienced pilots to fly the 737 Max more than 100 times with this new patch. These test flights will not crash because these experienced pilots will stay below the deadly angle of attack. The FAA will then rubber stamp their approval of the new MCAS program just like they did with the old MCAS program. As they say in the Mafia, the fix is already in. Passengers will then be lured back into flying on this unstable plane - – at least until the next 737 Max crash in a ball of fire. But if you want to know the truth about how to protect yourself and your loved ones from a horrific death, then keep reading. You are in for a real shock. I am sure that by the end of this report, you will agree that another 737 Max crash is inevitable.

The first question that is rarely asked by the corporate media (or if it is asked is only superficially answered) is why the Boeing 737 Max needed the deadly MCAS program in the first place?

This important question is typically brushed off with a couple of sentences about how the new engines were too big to fit under the wings and so the engines had to be moved forward and up a few inches. Moving the engines caused the nose of the plane to rise too much – which might lead to a stall and loss of control of the plane. MCAS was added to “fix this problem” and prevent the nose from going too high.

All of these sentences have a grain of truth. But they are also hiding some rather ugly facts about the real origins and purpose of MCAS.

For example, did you know that moving such heavy engines that far forward and that far up had never been done before on any commercial airline in the history of aviation? Because this monster had never existed before, there was no way of accurately determining the effect this huge gamble would have. It was like going to Vegas and betting a trillion dollars (as well as hundreds of lives) on the roll of the dice – only to have the dice come up snake eyes. It is amazing how such an important detail is rarely if ever mentioned by the corporate media. Instead the press, the FAA and Boeing all act as if moving the engine one foot forward and one foot up on the airplane was no different than changing the seating arrangements to fit a few more seats on the plane.

We will later review the convoluted history of why and how such an extreme design change was needed. For now, all you need to know is that MCAS was created to address a problem whose true magnitude was not really know until the first prototypes of the 737 Max were flown in 2016. When Boeing learned that their gamble had come up snake eyes, there was so much money on the line that Boeing was forced to hide the truth from the FAA, from airline carriers and from airline pilots and even from their own test pilots. Boeing was boxed into a corner. They were forced to Double Down on MCAS. Boeing never intended to increase the power of MCAS from 0.6 degrees to 2.5 degrees. But they were FORCED to make this change. This is the important hidden back story that has not yet been revealed. This is the biggest lie about MCAS.

Why Boeing Lied to the FAA about MCAS
To see what really happened, let’s take a closer look at one of the most shocking admissions by Boeing – that Boeing lied to the FAA and to Airline Carriers and to pilots about the real function and degree of control that MCAS was designed to use when taking over the 737 Max. Boeing initially hid MCAS entirely from air carriers and pilots. They also deliberately misled the FAA about MCAS.

Initially, from 2015 to November 2018 (one full month after the Indonesian Crash), Boeing told the FAA that MCAS was merely an optional feature that, if it was ever triggered, would only change the angle of the airplane stabilizer (also known as the tail wing flaps) by less than one degree – specifically 0.6 degrees. This was described in a now infamous 2015 report to the FAA written by Boeing and called the System Safety Analysis for MCAS. This document, written by Boeing as part of the FAA Certification process, has never been shared with the public. But it has been described in several reports.

To the public, 0.6 degrees does not sound like much. But someone at the FAA either knew or should have known that tail wing flaps exert a huge level arm effect on the rest of the airplane. This means that a very small change at the back of the plane can result in a very large change at the front of the plane. Understanding this lever arm effect is crucial to understanding why the pilots of the two 737 Max planes were not able to stop the planes from crashing despite their best efforts.

A better way to look at the 0.6 degree change made by MCAS is to compare it to the maximum possible change of the tail wing flap – which is 5 degrees. A 5 degree change in the stabilizer or tail wing flap is capable of causing the plane to go in a steep 40 degree dive because the lever arm is about 8 to 1.

This is why both 737 Maxes were at a 40 degree nose down angle when they crashed. It is likely that the stabilizer tail flaps for both planes were forced into the maximum 5 degree nose down position by their malfunctioning MCAS systems when they crashed. MCAS mis- setting of the tail flaps combined with this 8 to 1 lever arm is what ultimately caused both crashes.

Below is a crude drawing which attempts to show how small changes in the very back of the plane can have huge effects at the front of the plane due to this 8 to 1 lever arm.

The green downward pointing arrow is the all important Center of Gravity of the plane. Think of the wings of this plane as the center of a teeter totter which has a very long end on one side – the tail. A very small change or push up of 5 degrees on the tail of the plane can cause a very steep 40% dive at the nose of the above plane.


Therefore, when Boeing told the FAA that MCAS would only change the back flap by 0.6 degrees, what they were really saying was that MCAS would lower the nose of the plane by 8 times 0.6 degrees or 4.8 degrees. Put more simply, each time MCAS was automatically activated, the plane would automatically take about a 5 degree nose dive. This at least was the initial plan.

The initial MCAS plan was dangerous enough. But Boeing next did something almost unspeakably dangerous. In 2016, when the first 737 Max was produced and subjected to testing, Boeing learned that the actual 737 Max was much more unstable than its designers had initially predicted. According to Wikipedia, the first 737 Max performed its first flight on January 29, 2016. These early Boeing test flights of the first four 737 Max planes in 2016 revealed that the new 737 Max was much more unstable than original estimates that Boeing had provided to the FAA in a 2015 report. It is stunning that the 0.6 degrees of adjustment originally planned for MCAS would not be enough. Boeing therefore increased the MCAS adjustment from 0.6 degrees to 2.5 degrees – about four times more than the original estimate given to the FAA. Ask yourself: Why did Boeing not just change MCAS to 1 degree or 2 degrees?

Once again, the public is being misled as 2.5 degrees would not seem to be that much. But the public is used to thinking in terms of a 360 degree circle. Instead, you need to think in terms of the 8 to 1 lever arm that the change in the tail flap has on the front of the plane. A 2.5 degree change in the back flaps (at a rate of one degree every four seconds) will change the angle in the front of the plane by 8 times 2.5 degrees or 20 degrees. This 20 degree change occurs over a period of just under 10 seconds. This is a huge and shocking change for any airplane.


Here is the description from a March 17 2019 Seattle Times article about the 2015 Boeing report called the System Safety Analysis for MCAS:

“The original Boeing document provided to the FAA included a description specifying a limit to how much the system could move the horizontal tail — a limit of 0.6 degrees, out of a physical maximum of just less than 5 degrees of nose-down movement…. That (MCAS) limit was later increased after flight tests showed that a more powerful movement of the tail was required to avert a high-speed stall, when the plane is in danger of losing lift and spiraling down… After the Lion Air Flight 610 crash, Boeing for the first time provided to airlines details about MCAS. Boeing’s bulletin to the airlines stated that the limit of MCAS’s command was 2.5 degrees...That number was new to FAA engineers who had seen 0.6 degrees in the safety assessment.”

“The FAA believed the airplane was designed to the 0.6 limit, and that’s what the foreign regulatory authorities thought, too,” said an FAA engineer. “The numbers should match whatever design was tested and fielded.”

“The former FAA safety engineer who worked on the MAX certification, and a former Boeing flight controls engineer who worked on the MAX as an authorized representative of the FAA, both said that such safety analyses are required to be updated to reflect the most accurate aircraft information following flight tests.”


A later article added that even the Boeing test pilots who tested the 737 Max in 2016 were never told about the increase in the power of MCAS from 0.6 degrees to 2.5 degrees. This raises the likelihood that the more powerful MCAS system was never subjected to adequate field testing before the first commercial 737 Max was shoved out the door in the middle of 2017. It is also likely that due to the rush to make the 737 Max, that neither the new engine placement or the new more powerful MCAS system were ever tested in a wind tunnel. It is also likely that Boeing never updated their System Safety Analysis for MCAS – as was required by law. In short, the 737 Max was certified under false pretenses.

The MCAS Monster is turned into an Infinite Loop
The FAA, Airline Carriers and pilots were also never told that an Infinite Loop repeating function had been added to MCAS sometime after the System Safety Analysis for MCAS was provided by Boeing to the FAA in 2015.

Boeing was so concerned about the extreme instability of the 737 Max that they also added an infinite loop repeat function to MCAS – forcing MCAS to repeat the 2.5 degree nose drop every ten seconds. With the Indonesian crash, this MCAS fatal loop repeated 11 times before the plane crashed. The Ethiopian plane was subjected to 5 cycles of this stupidity before it dived into the desert.

MCAS will nose drive to 10 seconds and then pause for 5 seconds and then repeat the 2.5 degree nose dive process. Thus, in as little as 25 seconds a 737 Max – by design - can go from a normal level flying position to a 40 degree death dive.

On July 5 2017, not knowing any of these facts about MCAS, the FAA certified the Boeing 737 Max including MCAS in the following legal document:


This document was then updated on April 17 2019 – apparently as a backdoor certification of the revised MCAS settings. Here is a quote from this document:

“The purpose of this revision is to add the B-737-7, B-737-8200, and Maneuvering Characteristics Augmentation System (MCAS). In Appendix 3, the Design Differences Table from the Boeing 737-800 to the Boeing 737-8 is revised to include ATA 27 Flight Controls addition of MCAS… The evaluation was conducted during August 2016… In March 2019, the FSB conducted an evaluation of the modified Maneuvering Characteristics Augmentation System (MCAS) for training and checking differences determination. The system enhancement is incorporated on all MAX series aircraft. The MCAS system was found to be operationally suitable.”

This FAA report is a prime example of FAA rubber stamping whatever Boeing wants.

Why the FAA had to be kept in the dark about the more powerful MCAS
There is no way the FAA would have approved such a powerful new MCAS device had they known about it in 2016. There is no way any airline carrier would have bought such an unstable plane had they known about it. This is why Boeing had to keep this new more powerful MCAS program a secret. This is why Boeing never told the FAA about the change in MCAS until November 2018 - a full month after the Indonesian crash.

How Pilots were kept in the dark

A pilot for a US airline told managers months before October’s Lion Air crash in Indonesia that he was uncomfortable with the level of training he had received before he was scheduled to fly the Boeing 737 Max for the first time. But when he asked for more training, he faced difficulties in getting it—and even a form of reprimand. Like pilots at other US airlines using the 737 Max—which has been involved in two deadly crashes in less than five months that have killed nearly 350 people—this pilot was only required by the US Federal Aviation Administration (FAA) to take a two hour video tutorial on the new jet, as he was already certified to fly earlier variants of the 737 aircraft, on which the Max is based. This video tutorial did not even mention MCAS.



The pilot told his superiors he wasn’t comfortable flying the plane and requested simulator training. “I was going to see the airplane for the first time 45 minutes before departure, and have 45 minutes to adjust to this new aircraft, after which I was going to have 189 people in the back that I was responsible for,” he said. “So I filed a report with the company that I’m not comfortable flying as a pilot in command of this.”

His simulator request was denied as the carrier didn’t have simulators for the Max—even now, few airlines have Max simulators ready for training. A request to fly with an instructor the first time was also denied initially. Eventually, after a 45-minute conversation with the head of the airline’s 737 training department, he said the airline agreed that he could fly with an instructor on his first Max flight, which was scheduled for July between two US west coast cities.

“When we arrived in Los Angeles there was no instructor and so I called the flight duty manager to ask where the instructor was and he said he’d call back,” said the pilot. A few minutes later his chief pilot called him to say that he was off the trip if he was unwilling to fly.

“I was punished not just from being taken off the trip and having the pay subtracted from me but by having a ‘missed trip’ put in my schedule, which is the same as same as not showing up for the trip,” he said. “I’ve never had a missed trip and I was shocked that even though I was sitting in the seat in the airplane when I was taken off the trip, that I was given a missed trip.”

The missed trip amounted to about $3,000 in lost pay, as well as being a black mark on his record of reliability. He raised the issue with the union, and filed reports internally and with the FAA. As information about his experience percolated to other pilots, several told him they had shared his concerns on training for the Max. “After this happened it became pretty well known, and since then I’ve probably had, I’m going to guess, 50 pilots speak to me,” he said.

The video tutorial assigned to pilots before the Lion Air crash did not cover a new anti-stall flight system capable of sharply pointing the plane downward. That system is called the Maneuvering Characteristics Augmentation System, or MCAS, for short. Another vital change linked to the new system—that a control column to counteract such maneuvers would no longer work as it used to—was also not communicated to pilots.

The pilot said his concerns about the 737 Max—which he eventually flew for the first time only in December, less than two months after the Lion Air crash, with an instructor who had also previously not flown the aircraft either—deepened after the Ethiopian disaster.

“I assume every 737 pilot in the world was briefed extensively after the Lion Air crash” to deal with automatic nose-down maneuvers by the flight system, he said. “So I kind of harbor a secret concern that maybe there’s something bigger than this and maybe just turning off [switches to override MCAS] isn’t going to fix the problem. I hope that’s not correct, I hope it will, but part of me says that it’s bigger than that and it’s not going to work.”

The Wall Street Journal reported this week that black-box data shows the Ethiopian pilots had carried out steps recommended by Boeing and the FAA in the wake of the Lion Air crash. But they were unable to get the plane to climb again, and appear to have reversed some of them. The plane crashed six minutes after takeoff.

Separately, a NASA-run database of confidential safety reports from US pilots recorded complaints from at least two pilots who flew the Max who said that they experienced the plane’s nose pitching down when they were in autopilot, which they were able to stop by shutting off autopilot. However MCAS is not supposed to activate when pilots are in autopilot mode—only when they are in manual flight mode. Boeing said it could not comment on those reports.

According to Reuters, the doomed Lion Air cockpit voice recorder revealed how pilots scoured a manual in a losing battle to figure out why they were hurtling down to sea.

Boeing didn’t tell Southwest Airlines and other carriers when they began flying its 737 MAX jets that a safety feature found on earlier models that warns pilots about malfunctioning sensors had been deactivated, according to government and industry officials. Here is a statement from Southwest Airline issued on April 28 2019:

“Upon delivery (prior to the Lion Air event), the AOA Disagree lights were depicted to us by Boeing as operable on all MAX aircraft, regardless of the selection of optional AOA Indicators on the Primary Flight Display (PFD). The manual documentation presented by Boeing at Southwest’s MAX entry into service indicated the AOA Disagree Light functioned on the aircraft, similar to the Lights on our NG series. After the Lion Air event, Boeing notified us that the AOA Disagree Lights were inoperable without the optional AOA Indicators on the MAX aircraft. At that time, Southwest installed the AOA Indicators on the PFD, resulting in the activation of the AOA Disagree lights - both items now serve as an additional crosscheck on all MAX aircraft.”

Southwest’s cockpit crews and management didn’t know about the change for more than a year after the planes went into service. They and most other airlines operating the Max globally learned about it only after the fatal Lion Air crash last year led to scrutiny of the plane’s revised design. “Southwest’s own manuals were wrong” about the status of the alerts, said Southwest pilots union president, Jon Weaks. Since Boeing hadn’t communicated the modification to the carrier, the manuals still reflected incorrect information.

The FAA did not respond to a query on whether, prior to the Lion Air crash, US pilots had expressed concern to the regulator about the level of training they had received on the Max.

Did Boeing Turn off Pilot Access to an Essential Safety Feature?
Boeing clearly wanted MCAS to run as a secret and independent process to prevent what Boeing correctly interpreted as a huge and dangerous risk of a 737 Max nose up stall. However, according to a shocking report from the Seattle Times, Boeing may have inadvertently changed the Controls of a crucial “auto-disable” switch in the cockpit of the 737 Max. I have not been able to find any other report to confirm the claims made in this Seattle Times article and I have a hard time believing this claim is true. If it is true, then it borders on criminal negligence. Here is a picture of the switches that Boeing may have altered:

Stab Trim Cut-Out Switches


Here is the claim made by the Seattle Times: “In the middle of Boeing 737 cockpits, sitting between the pilot seats, are two toggle switches that can immediately shut off power to the systems that control the angle of the plane’s horizontal tail. Those switches are critical in the event a malfunction causes movements that the pilots don’t want. And Boeing sees the toggles as a vital backstop to a new safety system on the 737 MAX – the Maneuvering Characteristics Augmentation System (MCAS) – which is suspected of repeatedly moving the horizontal tails on the Lion Air and Ethiopian Airlines flights that crashed and killed a total of 346 people. But as Boeing was transitioning from its 737 NG model to the 737 MAX, the company altered the labeling and the purpose of those two switches. The functionality of the switches became more restrictive on the MAX than on previous models, closing out an option that could conceivably have helped the pilots in the Ethiopian Airlines flight regain control.

Boeing declined to detail the specific functionality of the two switches. But after obtaining and reviewing flight manual documents, The Seattle Times found that the left switch on the 737 NG model is capable of deactivating the buttons on the yoke that pilots regularly press with their thumb to control the horizontal stabilizer. The right switch on the 737 NG was labeled “AUTO PILOT” and is capable of deactivating just the automated controls of the stabilizer.

On the newer 737 MAX, according to documents reviewed by The Times, those two switches were changed to perform the same function – flipping either one of them would turn off all electric controls of the stabilizer. That means there is no longer an option to turn off automated functions – such as MCAS – without also turning off the thumb buttons the pilots would normally use to control the stabilizer.

Peter Lemme, a former Boeing flight-controls engineer who has been closely scrutinizing the MAX design and first raised questions about the switches on his blog, said he doesn’t understand why Boeing abandoned the old setup. He said if the company had maintained the switch design from the 737 NG, Boeing could have instructed pilots after the Lion Air crash last year to simply flip the “AUTO PILOT” switch to deactivate MCAS and continue flying with the normal trim buttons on the control wheel. He said that would have saved the Ethiopian Airlines plane and the 157 people on board.”

The Seattle Times article is behind a pay wall. Here is a link to an article discussing this claim that is not behind a pay wall:


If this claim turns out to be true, then some people at Boeing should go to jail. I disagree that members of the FAA should go to jail because they were in fact kept in the dark for years about the true power of MCAS.

Federal Aviation Administration safety inspectors and supervisors were also unaware of the MCAS change.

Boeing had a trillion dollars in reasons for keeping the FAA, pilots and airlines in the dark about MCAS. Boeing and the FAA and their airline partners are still keeping the public in the dark about the 737 Max.

We now know that the jack screws from the horizontal tail stabilizer were recovered from both crashes. Both jack screws showed that the planes had been oriented in a full 40 degree dive position with the nose pointing down.

A “screw-like device” found at the scene of the deadly Ethiopian Airlines crash indicates the plane was “configured in a nose dive” when it hit the ground, killing all 157 people on board, Bloomberg News reports. On Thursday, Daniel Elwell, the Federal Aviation Administration’s acting chief, said evidence found at the scene of the disaster led to the US. decision to ground Boeing 737 Max 8 and 9 series planes. “The piece of evidence was a so-called jack screw, used to set the trim that raises and lowers the plane’s nose,” Bloomberg News reports, quoting an unnamed source close to the investigation.



Somewhere in this mess, investigators found the Jack screw which was in a full 40 degree nose down position. Here is a quote about the Indonesian descent angle:

The last ADS-B data that we have from Flightradar24 has the aircraft at an altitude of 425 ft, a ground speed of about 360 knots, and a descent rate of 30,976 fpm. That translates to an approximate true airspeed of 472 knots and a descent angle of about 40 degrees. http://mh370.radiantphysics.com/2018/11/04/crash-debris-from-lion-air-jt610-provides-clues-about-mh370/


Note that when the horizontal stabilizer is pushed up the maximum of 5 degrees, the nose will be pushed down 40 degrees due to an 8 to 1 lever arm. It takes MCAS about 25 seconds to push the jack screw enough to move the stabilizer up 5 degrees – moving the nose down 40 degrees. MCAS had done the job it was intended to do. It had prevented the 737 Max from going into a nose up stall. Sadly, MCAS also put the nose into a 40 degree nose down death dive.