Boeing's 737 MAX Disaters

This case was prepared from public sources by James Quinn, Managing Director, CaseStudy Co., under the supervision of Professor John Sterman.

Copyright © 2023 John Sterman. This work is licensed under the Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 Unported License. To view a copy of this license visit http://creativecommons.org/licenses/by-nc-nd/3.0/ or send a letter to Creative Commons, 171 Second Street, Suite 300, San Francisco, California 94105, USA.

20-199 May 2, 2023

Boeing’s 737 MAX 8 Disasters

John Sterman and James Quinn

On October 29, 2018, a nearly new Boeing 737 MAX 8 jet plunged into the Java Sea at 400 miles per

hour, killing all 189 people onboard. The sudden and rapid descent of Indonesia’s Lion Air Flight 610

commenced at 5,000 feet, just 11 minutes after taking off from Jakarta’s Soekarno-Hatta International

Airport. Captain Bhavye Suneja and First Officer Harvino, who went by a single name as was common

in Indonesia, contacted air traffic control requesting immediate return to Jakarta before losing control

of the aircraft. The plane crashed into the sea, “hitting the water with such force that some metal fixtures

on the aircraft disintegrated.”1

The accident initially seemed to be a senseless and anomalous tragedy. Air safety, enforced in large

part by the certification process of the Federal Aviation Administration (FAA), was enjoying an

exemplary record: Globally, the five-year worldwide average stood at one fatal airliner crash for every

2.5 million to 3 million flights. In the United States, airline safety had reached record levels, with only

one passenger fatality in more than 10 years.2

Boeing’s initial response to the crash focused on Lion Air’s airline maintenance procedures and

suggested the pilots were at fault.3 Nonetheless, about eight days later, on November 6, 2018, Boeing

issued a bulletin to all 737 MAX 8 and 737 MAX 9 operators indicating that “erroneous angle-of-attack

data” could result in “uncommanded nose-down movement of the aircraft and that this action can repeat

until the related system is deactivated.”4 The Boeing bulletin provided additional instructions to pilots

who might encounter such a dangerous situation. On November 7, 2018, the FAA followed by issuing

an Emergency Airworthiness Directive requiring Boeing to revise the operating procedures in its flight

manual for the 737 MAX aircraft. Of specific concern was the new Maneuvering Characteristics

Augmentation System (MCAS), software designed to prevent the aircraft from stalling by automatically

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pushing the nose of the plane down when a high angle of attack (AOA), or nose-up condition, was

detected.

Officially, Boeing, including CEO Dennis Muilenburg, repeatedly declared “…the 737 MAX is safe.”5

But, as investigative reporter Peter Robison documented, “Behind the scenes, some of the largest and

most respected airlines in the world were screaming that Boeing had hidden the existence of potentially

deadly software inside their planes.”6 Internal communications that Boeing handed over to the U.S.

Department of Justice and Congressional investigators would later show that the company’s own

engineers and test pilots had known about the MCAS problem well before the crashes.

After the Lion Air crash, Boeing rushed to redesign MCAS. Boeing Vice President Mike Sinnett

initially promised it would take “not a year, but…maybe six weeks-ish” to “tame the system.”7 By

March 2019, the revisions were still not completed.

Then, on March 10, 2019, shortly after Ethiopian Airlines Flight 302 took off from Addis Ababa Bole

International Airport bound for Nairobi, Kenya, Captain Yared Getachew and First Officer Ahmed Nur

Mohammod Nur struggled to ascend at a stable speed.8 Getachew sent out a distress call, but contact

with air traffic control was lost six minutes into the flight. The same model Boeing MAX 8 that had

plummeted into the Java Sea crashed near Bishoftu, a town southeast of Addis Ababa. All 157 onboard,

hailing from 35 different countries, were killed.9

A maelstrom of questions immediately followed, from maintenance crews in Indonesia and Ethiopia,

airlines and pilots flying the MAX 8 around the world, Boeing leadership at its Chicago-based

headquarters, the FAA and U.S. Congress, and the families of the victims. High-stakes public disputes

arose over the root causes of the crashes. U.S. Congressman Sam Graves declared, “Pilots trained in

the United States would have been able to handle the emergencies on both jets.”10 Others, however,

blamed MCAS and a flawed design process at Boeing. Still others faulted the FAA. A subsequent report

by the U.S. Department of Transportation’s Inspector General, entitled “Weaknesses in FAA’s

Certification and Delegation Processes Hindered Its Oversight of the 737 MAX 8,” identified

“limitations in FAA’s guidance and processes that impacted certification….” These included

“communication gaps,” “management and oversight weaknesses,” and “process and structure [that] do

not ensure [FAA] personnel are adequately independent.”11

On March 13, 2019, under pressure from the Indonesian and Ethiopian governments, airlines, pilots,

the public, and the families of the 346 dead, the President of the United States Donald Trump ordered

the grounding of all 737 MAX aircraft. Several independent review boards were created to identify the

root causes of the two crashes and the changes regulators would require Boeing to implement before

the aircraft could return to service.

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Boeing’s best-selling plane remained grounded for 21 months, while customers continued to cancel

orders. Through the end of October 2020, Boeing removed 595 MAX orders from the backlog and

canceled a further 448, a total loss of 1,043 orders, leaving a backlog of 3,320. Boeing’s rival Airbus

had a backlog of 5,956 jets for its A320neo family, a direct competitor to the 737 MAX.12

On November 18, 2020, just over two years after the Lion Air crash, FAA Administrator Steve Dickson

signed an order permitting the 737 MAX to return to commercial service.13 At the time of Dickson’s

order, the COVID-19 pandemic had slashed global air travel. Airlines announced plans to return their

737 MAX aircraft to service slowly.

Yet major questions remained as passengers once again began flying on the MAX 8, which Boeing

rebranded the 737-8.14 What role, if any, did company engineers play in causing the two catastrophes?

What about their managers? Their test pilots? What role did Boeing’s CEO, board, and other senior

leaders play in shaping the processes, procedures, and corporate culture that may have set the stage for

the disasters? Why didn’t the FAA detect the flaws in the design before allowing the 737 MAX 8 to

enter service? How could future disasters be prevented?

Air Safety

Over many decades, commercial aviation had become much safer. Technical innovation in engines,

airframes, cockpit instrumentation, communications, software, and control systems—together with

better procedures and stronger regulations governing aircraft testing, certification, pilot training,

operations, and air traffic control—all contributed to improving safety.

Measured by accidents per passenger miles flown, the improvements were impressive. In 2018, the

National Safety Council (NSC) reported only 1 death per 100 million passenger miles on scheduled

airlines in the U.S. Exhibit 1 shows U.S. commercial aviation accidents, 1975–2018.

However, the number of flights, flight hours, and passenger miles traveled per year all exploded as

people around the world became more affluent and average fares fell. From 2010 to 2019 (the year

before COVID-19 drastically cut airline travel), passengers carried by scheduled commercial air traffic

grew from 2.7 billion to 4.5 billion worldwide, and total flight miles grew from less than 3.1 trillion to

nearly 5.4 trillion passenger miles.15 The industry formed a complex web with more than 1,400

scheduled airlines, 26,000 aircraft, 3,900 airports, 173 air navigation centers, 360,000 pilots, and 86,000

air traffic controllers.16

The growth in air travel meant that the accident rate did not fall as much as data on accident per flight

or per passenger mile suggested. Between 1959 and 2008, 33.8 commercial jet accidents per year

occurred worldwide, 35% of which involved fatalities. Between 2009 and 2018, 41.4 accidents per year

occurred, 13% of which were fatal.17

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The root causes of accidents remained a hotly contested topic. Human error was often the go-to

explanation. In a 2006 study, the FAA noted, “Although percentages vary, most would agree that

somewhere between 60%–80% of aviation accidents are due, at least in part, to human error.”18

Safety experts, however, argued that most human errors were the result of poorly designed equipment

and systems.19 In addition to focusing on “personal safety”—roughly speaking, admonishing people to

be careful—designers focused on increasing “process safety”—designing an intrinsically safe system

that minimized opportunities for and consequences of human error. As safety expert and psychologist

James Reason noted, “Though we cannot change the human condition, we can change the conditions

under which humans work.”20

The Boeing Company

Incorporated in 1916 by timber baron William E. Boeing, the company’s first contracts were with the

U.S. Navy, for which Boeing produced seaplanes, patrol flying boats, and torpedo bombers. During

World War II, Boeing produced nearly 100,000 aircraft, including the famous B-17 Flying Fortress.

Between 1942 and 1944, the company ramped up production from 60 to 362 B-17s per month. After

the war, Boeing went on to develop the B-52 Stratofortress strategic bomber and other critical military

aircraft. Boeing also developed the nation’s first commercial jet airliner, the Boeing 707, delivering the

first one to Pan Am to serve a transatlantic route.

Boeing became the preeminent player in the commercial airline industry. Author John Newhouse wrote:

Back in the 1970s and early 1980s, four companies divided the turbulent business of making and

selling passenger airplanes. One of them, the Boeing Company, was dominant. The other two big

American players—the Lockheed Aircraft Corporation and the McDonnell Douglas Corporation—

labored in the wake of their own mistakes. Lockheed’s were terminal, and McDonnell Douglas,

known in the trade as McDac, hadn’t come to terms with reality. The reality was that a small

European company called Airbus Industrie, generally known only as Airbus, had abruptly become

not just a player but a mortal threat. Simply put, Airbus was eating McDac’s lunch.

In the 1980s, …Boeing was universally judged one of America’s best and most admired companies,

partly because its sales abroad of large commercial airplanes were the country’s biggest export, and

partly because it had learned to build these airplanes better, faster, and cheaper than anyone else

had done. ‘World-class’ was Boeing’s lofty but accurate characterization of itself.21

By the end of 1990, Boeing held 62% of the commerical airline market, with sales of $20.3 billion and

earnings of $973 million.22 McDonnell Douglas (23%) and Airbus (15%) trailed far behind.23

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Thornton “T” Wilson

One of Boeing’s legendary leaders, Thornton “T” Wilson, was credited with shaping much of the

company’s success. With a bachelor of science degree in aeronautical engineering from Iowa State

University and a master of science degree from California Institute of Technology, Wilson joined the

company in 1943 to work on its bomber programs. He became president of Boeing in 1968, CEO in

1969, and chairman in 1972. A hands-on manager who had worked on the factory floor, Wilson

understood every blue-collar job involved in the production process, and engaged closely with

employees at all levels. Newhouse commented: “Wilson would sit down with factory workers at lunch

in the cafeteria and find out what was going on in their various operations; and then if it was advisable,

he would take up what he’d learned with the relevant managers.” As one former executived noted, “He

ran the company. It did not run him.”24

During Wilson’s leadership and soon after his retirement in 1986, Boeing became the market leader in

commercial aircraft, defense, space, and security systems. Company engineers took on some of the

most challenging work in the industry, including high-visibility U.S. government contracts. In 1980,

Boeing initiated a study of the space station concept with NASA. In 1982, Boeing engineers designed

a solar power satellite system capable of providing power to millions of homes.25 In 1988, the company

delivered to the U.S. Army the first Avenger “air defense system,” one of several Cold War innovations.

And, in 1994, Boeing Computer Services won the contract to design software for the Space Shuttle

Program. Meanwhile, four years earlier, the Boeing 737 became the best-selling jetliner in the world.

During Wilson’s tenure, it was common for employees to spend their entire career at Boeing, as was

the case with Wilson himself, forging a “social contract” between workers and the company. Boeing

researchers Leon Grunberg and Sarah Moore summarized the company ethos:

Management of the company was anchored in loyalty and promoting through the ranks. Indeed, so-

called Heritage Boeing employees were extremely proud of building innovative, safe, quality

products, such as the 707 and 747, airplanes that set the global standard in commercial aviation

when launched. Executives told their employees—and the employees believed—that they were

number one in the world, as indeed they were until Airbus gradually ate into Boeing’s market share

and achieved parity in deliveries in the early 2000s.26

Years after retiring from Boeing, many employees reflected nostalgically on the Boeing family

atmosphere, where a deep commitment to quality engineering and pride in the work carried the day.

Grunberg and Moore explained:

Boeing offered lifelong employment and the promise of a meaningful career. Opportunities for

growth and promotion were endless, and despite the cyclical nature of the industry and the

accompanying layoffs, one could work at Boeing for life, as could members of one’s family. It was

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commonplace for one’s parents, grandparents, children, siblings, aunts, and uncles to work for the

company.27

While the company employed thousands of people in the state of Washington’s Puget Sound region,

many recalled feeling like they were members of a “Boeing family.” As one longtime engineer said,

“I’ve been to weddings. I’ve been to funerals and Christmas parties. I’ve got friends I’ve done dog

sitting for. Our families still get together.” The emotional ties employees had with Boeing went beyond

coworkers and supervisors and included the airplanes they built and the buildings in which they

worked.28

Acquiring McDonnell Douglas

When I say I changed the culture of Boeing, that was the intent, so it’s run like a business rather

than a great engineering firm. It is a great engineering firm, but people invest in a company

because they want to make money.

– Harry Stonecipher, 2004, former president and CEO of

McDonnell Douglas and then Boeing29

In December 1996, Boeing announced its intention to purchase long-time rival McDonnell Douglas in

a stock swap valued at $13.3 billion. It was the 10th-largest U.S. merger at that time and the largest in

the aerospace industry. Under the terms of the agreement, 0.65 Boeing shares were exchanged for each

McDonnell Douglas share. The implied value of $62.89 per share represented a 21% premium on

McDonell’s closing price of $52 when the deal closed on July 31, 1997.

On its face, joining the two companies, which analysts estimated would yield in excess of $48 billion

in 1997 revenue—$28 billion from Boeing and $20 billion from McDonnell Douglas—would bring

together complementary product lines and internal capabilities, while helping to mitigate market risk

for each. “We’ve looked very carefully at all of our programs,” said Philip Condit, then Boeing’s

president and CEO. “We believe that dramatically they are complementary. There are some overlaps,

but they’re very, very minor.”30

Whereas Wilson knew many frontline employees by name and often met with them, Boeing’s

headquarters and senior management were moved to Chicago, about 2,000 miles from the commercial

aircraft division. The reporting structure changed so that top engineers reported first to business leaders

in each division and second to the chief engineer. In the years following the merger, many longtime

Boeing employees lamented what they perceived as a fundamental change from “an engineering and

‘family’ culture to a ‘team’ and shareholder value culture.”31

Other changes included the computerization of parts ordering, a shift to lean manufacturing to reduce

cycle times, increased use of outsourcing and global partnering—and approximately 50,000 layoffs

between 1999 and 2003.32

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Some observers noted growing conflict between the engineering culture that Wilson had built with a

“bean counter” approach that emerged among many of his successors, particularly after the merger.

“Boeing’s critics, in-house as well as external, complain about a heavy presence of inexperienced

business-school types and too little listening to the airline market,” said author John Newhouse.33

Kyle Smith, a business operations and corporate consultant with 30 years of experience at Boeing,

commented on the labor-management dynamic following the merger:

So you have a workforce that is highly disillusioned, that feels that leadership is out of touch.

Management deals with that by hiding and by being increasingly authoritarian. A culture of fear is

the only way they have of maintaining control. And it’s all done in an environment of encouraging

people to tell management what they think, which is absolutely the opposite of what management

actually wants them to do. So you get all of these double messages and double binds that you’re

putting the workforce in, of saying we want your input but when we get it you’re punished or held

back because of it. We want your input, but when you give it, you’re not a team player, because

team players only give us things that make us feel better.34

In the past, Boeing engineers with safety concerns could and would raise them even if doing so held up

progress until the issue was resolved.35 Carrie Conway was a 62-year-old hourly worker in 2012 with

26 years of experience with Boeing when she noted the difficulty she faced in presenting quality issues

to her boss while working on the 787 family of aircraft:

One day I’m working, and my lead brought all the parts out of storage. They were all wrapped up

in a paper, brown bag. This was a Monday morning, so all the tables were stacked with the

necessary parts to do whatever we were working on. So I started unwrapping mine, and you could

see chips in it, little tiny holes. And there were areas where you could see corrosion—corrosion has

a different look to it. So the first part I took to my lead, and I said, ‘Look at this.’ He said, ‘Oh,

can’t use that.’ Well, it took four parts to get one that I could use. When the inspector came in, I

called him over—I’d saved one of them. I said, ‘I want you to look at this part,’ and he goes, ‘Well,

that’s not acceptable,’ and I said, ‘Well, we got a whole warehouse full of them, you know. I had

to get to the fourth part to find an acceptable one.’

He went into the warehouse, started checking all these parts, and he came back and stopped

production. He figured about two-thirds of this order was pitted and corroded. Before the day was

over, his boss and my boss were standing on one side of the table. My inspector and I were standing

on the other side of the table. My boss was telling me I have to use these parts, and both of us said,

‘No, we’re not doing that.’ It took months. I’m not sure even when, because I ended up getting

transferred out of the building over it.36

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Enter Airbus

In the 1960s, European nations and aircraft companies felt the need to respond to U.S. industry

dominance in commerical aviation. Under Anglo-French-German leadership, many smaller European

aircraft makers were consolidated, and a new player entered the market: Airbus Industrie. Other

European nations joined in, with design and assembly spread across the Continent. The first Airbus,

the A300, was designed to be more efficient and less expensive than similar medium-sized American

jets, including Boeing’s. Yet Airbus had a rocky start. The first A300 flew in 1972, but by 1979 Airbus

had only delivered 26 aircraft, less than a tenth of Boeing’s 286 deliveries.

Nevertheless, Airbus steadily grew, expanding its product line and sales. Soon Boeing and Airbus

dominated the industry in a global duopoly, with smaller niche players such as Bombardier and Embraer

trailing behind.

In 1999, Boeing still supplied the majority of the market, delivering 573 new jets, compared to Airbus’s

294. But Airbus continued to build its product line and organizational, engineering, operational, and

marketing capabilities, successfully acquiring new customers. Airbus continued to cut into Boeing’s

market share and in 2003 delivered 305 new jets, outpacing Boeing’s deliveries for the first time.

Exhibit 2 shows aircraft deliveries and orders for Boeing and Airbus through 2019.

The 737 vs. the A320

Boeing and Airbus competed for the same customers and the same routes in every region of the world.

Each offered a family of aircraft spanning the entire market. Competition was intense. A major battle

involved Boeing’s 737 and Airbus’s A320 models. Author of Boeing versus Airbus John Newhouse

explained:

The low end of the market is covered by two single-aisle airplanes, Boeing’s 737 and Airbus’s

A320. They are roughly the same size, seating up to 190 people. Both are exceptionally successful,

having exceeded the most optimistic forecasts of their respective companies. The 737 is older and

has been steadily improved over the years. But the A320, a newer, slightly larger, and more

comfortable aircraft, is outselling the 737, not least in the low-cost market Boeing had

monopolized. 37

In December 2004, with orders surging for Airbus’s A320s, Boeing shook up its sales force, replacing

its head of sales.38

The success of the A320 raised the stakes in Boeing’s battle with Airbus, including the decision on

whether to develop and build a new aircraft. Newhouse wrote:

The decision to build a new LCA (Large Commercial Aircraft) alerts boards of directors and

shareholders to impending deficits, big ones. Indeed, the costs of any such venture can amount to

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betting the company, literally. A single deal with one airline can determine the fate of an airplane

on which billions of dollars have been invested. And the returns, if any, lie far ahead.39

The 737 MAX Program

Boeing’s products cover the entire commercial market. The 737 family had an average range of 4,000

miles and seating capacity of approximately 130 to 220 passengers. Exhibit 3 shows the Boeing 737

aircraft family from 1967 to 2017. Other families consisted of larger planes with longer ranges. Prices

varied from $89 million for the 737-700 to $442 million for the 777-9 (Exhibit 4). The average price

of the 737 MAX 8 was $122 million.40

The Boeing Commercial Airplanes (BCA) division launched the 737 MAX project in August 2011.

Within the 737 MAX family, the MAX 8 was the first to market, with the first delivery in May 2017.

The schedule was compressed compared to other development projects. Exhibit 5 shows select Boeing

Commercial Airplanes “Go Ahead” and “Initial Delivery” schedules for several aircraft development

projects. Exhibit 6 shows a timeline for the MAX 8 project including FAA certification actions.

The 737 MAX family came to market with high expectations for Boeing’s sales and profits, and those

expectations were soon exceeded. In 2017, Boeing led the industry in deliveries for the sixth

consecutive year, with the 737 MAX family earning the distinction of “the fastest-selling airplane in

Boeing history.”41 Boeing featured the MAX in its 2018 Annual Report:

The 737 is designed to be 14 percent more fuel efficient than today’s most efficient Next-

Generation 737s [launched in 1997] and 20 percent more fuel efficient than the original Next-

Generation 737s when they entered service. With new CFM International LEAP-1B engines, a

more efficient structural design, advanced technology winglets, and lower maintenance

requirements, the entire MAX family has been designed to offer exceptional performance,

flexibility, and efficiency.42

The 737 family continues to exceed expectations in the single-aisle market, with 745 net new orders

received and a company record of 529 airplanes delivered in 2017. Our 737 backlog now stands at

more than 4,600 airplanes.43

Exhibits 7 and 8 present Boeing’s financial performance during this period.

Anatomy of Two Disasters

In 2010, Airbus announced the development of the A320neo, a fuel-efficient plane that quickly captured

the attention of many carriers. In early 2011, Boeing’s CEO, W. James McNerney, received a phone

call from the head of American Airlines indicating that the company, a long-time customer, was

considering placing an order for hundreds of A320neo airplanes from Airbus.44 For Boeing, the stakes

were high. The American Airlines account represented billions in future revenue, and the loss of such

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a prominent customer could threaten Boeing’s market-share dominance. At the time, Boeing was

considering the development of a brand-new passenger airplane, with an expected development cycle

time of 10 years. To respond to the threat, McNerney and his team scrapped the plan to develop a new

plane, opting instead to update the 737. McNerney told a group of Wall Street analysts: “All of us have

gotten religion. Every 25 years a big moonshot—accumulating technologies and taking risks on some

additional ones and then producing a 707 or a 787—that’s the wrong way to pursue this business… .

The more-for-less world will not let you pursue moonshots.”45

The Boeing team hustled into action, launching the 737 MAX project three months after learning of

American Airlines’ potential defection. An engineer on the 737 MAX flight control team noted, “[The

company wasn’t] going to stand by and let Airbus steal market share.” 46 Months behind Airbus, Boeing

found itself in catch-up mode. As The New York Times reported, “The pace of work on the 737 MAX

was frenetic. … Engineers were pushed to submit technical drawings and designs at roughly double the

normal pace. Facing tight deadlines and strict budgets, managers quickly pulled workers from other

departments when someone left the MAX project.”47 As a Boeing engineer said, “The timeline was

extremely compressed. It was just go, go, go.”48 Management installed a countdown clock in a

conference room where program meetings were held as a constant reminder of “the value of a day.”49

According to a designer who worked on the 737 MAX flight controls, the design team at times found

itself producing 16 technical drawings a week—double the normal pace.50 A technician who assembled

wiring on the 737 MAX reported that many of the blueprints designers provided him were

uncharacteristically sloppy, reporting that management told him “instructions for wiring would be

cleaned up later in the process.”51 Mark Rabin, who worked in a flight test group that supported the 737

MAX, noted, “It was a climate that didn’t reward people willing to buck managers.”52

Behind the scenes, however, employees working on the 737 MAX shared, among themselves, concerns

about the hurried timeline and resulting slip-shod work. Some of their misgivings were revealed after

Boeing turned over internal texts and emails to the U.S. Department of Justice and Congressional

investigators.53 In an email exchange in May 2018, employees working on the 737 MAX lamented the

pressure they were under to quickly approve a large number of open design review issues (DRs):54

The conversation turned darker:

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Prior to the crashes, employees expressed their disdain for the way in which they perceived

management was undermining quality and safety. As one wrote,55

The Origin of MCAS

To compete head-to-head with Airbus’s 320, the 737 MAX needed larger, more powerful, and more

efficient engines. Boeing chose a new engine: the CFM LEAP-1B. However, as an analyst explained,

the new engine required a number of critical design changes:

Because they’re bigger, and because the 737 sits so low to the ground (a deliberate 737 design

choice to let it serve small airports with limited ground equipment), Boeing moved the engines

slightly forward and raised them higher under the wing. (If you place an engine too close to the

ground, it can suck in debris while the plane is taxiing.) That change allowed Boeing to

accommodate the engines without completely redesigning the 737 fuselage—a fuselage that hasn’t

changed much in 50 years.56

Exhibit 9 compares the engine size and placement for the 737 NG and 737 MAX.

In 2012, early in the design phase, engineers gathered at Boeing’s transonic wind tunnel in Seattle to

test the jet’s aerodynamics. Using a scale model with a wingspan comparable to that of an eagle57, they

discovered that the plane’s nose tended to pitch up during a specific “extreme maneuver.”58 As MIT

aeronautics professor R. John Hansman explained, “As I understand it, at high angles of attack the

nacelles—which are the tube-shaped structures around the [engine] fans—create aerodynamic

lift. Because the engines are further forward, the lift tends to push the nose up—causing the angle of

attack to increase further. This reinforces itself and results in a pitch-up tendency which if not corrected

can result in a stall.”59 If that self-reinforcing feedback caused the nose to pitch up high enough to cause

the aircraft to stall, the result could be catastrophic.

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The engineers worked to devise a countermeasure to what they viewed as a highly unlikely occurrence

and, after several attempts, developed new software intended to respond to the problem automatically.

The Maneuvering Characteristics Augmentation System or MCAS was originally designed to activate

only if the flight management computer detected both a high angle of attack (AOA) and high vertical

G-force. A high AOA indicated the nose was pitched up, and high G-force meant it was accelerating

upward. If triggered, MCAS would automatically move the horizontal stabilizer (at the tail of the

aircraft) to push the nose of the plane down (Exhibit 10). MCAS was created as a safety system

intended to correct what was originally believed to be a rare, but potentially dangerous, pitch-up

condition without requiring any pilot action.

Based on tests conducted during the design phase, engineers believed that the potential runaway pitch-

up condition would only occur during certain high-speed maneuvers. Consequently, MCAS was

originally designed to move the stabilizer 0.6 degrees over about 10 seconds, enough, at high speed, to

bring the nose down to a safe trim position. Further testing, however, revealed that the same pitch-up

could also happen at low speeds.60 To address this discovery, MCAS was reprogrammed to operate at

low speeds such as after takeoff and during the climb to cruising altitude. Because lower speeds required

more aggressive control actions, the modified software enabled MCAS to move the stabilizer down 2.5

degrees in about 10 seconds, more than four times faster. Additionally, low-speed maneuvers would

not generate high G-forces, so the G-force condition required to engage MCAS was dropped.61 MCAS

was designed to trigger again if the high AOA condition was still detected after five seconds.

Redundancy Made Optional

Engineers build redundancy into their systems to avoid “single points of failure,” in which the failure

of a single component causes an accident or stops the system from operating. Redundancy is standard

practice for critical components and systems in commercial aircraft. The revised MCAS, which no

longer required both a high AOA and high G-force to be triggered, now depended only on AOA data,

provided by AOA sensors, small vanes located near the nose of the aircraft. The sensors, however, can

go out of alignment or fail altogether due to mechanical and electrical faults, improper maintenance,

icing, bird strikes, and other causes. In 2019, CNN reported that since 2004, the FAA had received at

least 216 reports of AOA sensors failing or having to be repaired, replaced, or adjusted. The FAA had

also issued two directives involving AOA sensors for various Boeing aircraft models before the 737

MAX was released.62

To provide redundancy, the 737 MAX had two AOA sensors, one on each side of the nose. (The Airbus

320 and some other Boeing aircraft have three sensors to provide double redundancy.) However, MCAS

was designed to use data from only one of the sensors (alternating after each flight). Relying on just

one sensor created a single point of failure hazard. To address the possibility that the single sensor in

use failed or gave erroneous readings, the designers created a cockpit display showing the readings

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from both AOA sensors. The display was programmed to activate a cockpit “AOA DISAGREE” alert

if the readings differed by more than a few degrees (Exhibit 11).

However, whereas MCAS was activated automatically, without pilot action, the cockpit crew would

have to notice and act on an AOA DISAGREE alert. Further, the AOA indicator and disagree alert

were not standard equipment on the 737 MAX, although the AOA indicator had been on earlier models.

Boeing offered them as “add ons” at additional cost. Neither feature was required by regulators. Lion

Air, Ethiopian Airlines, and other carriers, including Southwest Airlines, had chosen not to pay extra

for these features. According to government and industry officials, “Boeing Co. didn’t tell Southwest

Airlines Co. 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.”63

Boeing issued an explanation:

The disagree alert was intended to be a standard, stand-alone feature on MAX airplanes. However,

the disagree alert was not operable on all airplanes because the feature was not activated as

intended.

The disagree alert was tied or linked into the angle of attack indicator, which is an optional feature

on the MAX. Unless an airline opted for the angle of attack indicator, the disagree alert was not

operable.64

Because MCAS relied on data from only one of the AOA sensors, 737 MAX planes that did not have

the optional AOA indicator and disagree alert would not directly report a problem with the sensor. In

fact, as documented in the 322-page report on the Lion Air crash issues by Indonesia’s Aviation Safety

Agency:

The sensor, provided second-hand by a Florida-based company called Xtra Aerospace, was not

calibrated correctly nor did Lion Air maintenance crews detect the error when they installed the

sensor the day before the crash (31 pages were missing from the aircraft’s maintenance log at the

time). The fault in the sensor meant that it was feeding incorrect information to MCAS.

The 737 MAX has a warning light that would have shown that the faulty sensor was disagreeing

with the working sensor on the other side of the aircraft’s nose. But a software bug meant that the

warning light was working only if Lion Air purchased a package of equipment Boeing sold only as

an option.65

FAA Certification

As Boeing engineers worked night and day to ready the 737 MAX for production, others took steps, at

the direction of their managers, to get the FAA to fast-track the certification process. The formal

certification process for the 737 MAX 8 began in 2012. Under FAA protocols, “only the significant

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differences” between the 737 MAX 8 and the previous model required certification.66 Boeing argued

that the differences between the 737 MAX and the previous 737 NGs (next generation) were not

significant and positioned MCAS as a minor addition to existing speed trim functionality, as revealed

in minutes of a meeting on June 7, 2013:67

Boeing succeeded in positioning MCAS as a minor modification to earlier models, as detailed in a 2020

report by the U.S. Department of Transportation Office of the Inspector General:

Early in the process, Boeing included limited information in initial briefings to FAA on the MAX’s

flight control software, MCAS, which subsequently has been cited as a contributing or potentially

contributing factor in both accidents. However, Boeing presented the software as a modification to

the existing speed trim system that would only activate under certain limited conditions. As such,

MCAS was not an area of emphasis in FAA’s certification efforts and therefore did not receive a

more detailed review or discussion between FAA engineers and Boeing. Instead, FAA focused its

efforts on areas it identified as potentially high risk, such as the aircraft’s larger engines, fly-by-

wire spoilers, and landing gear changes. As a result, FAA was not well positioned to mitigate any

risks related to MCAS.68

Meanwhile, in 2016, about one-third of the way through testing, Boeing engineers increased the

stabilizer nose-down deflection each time MCAS was activated at low speeds, from 0.6 degrees to 2.5

degrees, and removed the G-force condition initially required to trigger MCAS. An analyst explained:

“On the stabilizer, maximum nose down is about 4.7 degrees away from level flight. So with the new

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increased authority to move the stabilizer, just a couple of iterations of the system could push it to that

maximum.”69

Mark Forkner, chief technical pilot for the 737 MAX, was apparently not informed about these changes,

but discovered them in the flight simulator, complaining about it to a colleague on November 16,

2016:70

According to the Inspector General’s report, Boeing failed to report the MCAS changes to the FAA

during the certification process:

During this timeframe, Boeing also began modifying MCAS as a result of flight testing, including

significantly increasing MCAS’s ability to lower the aircraft’s nose automatically under certain

conditions. However, Boeing did not submit certification documents to FAA detailing the change.

FAA flight test personnel were aware of this change, but key FAA certification engineers and

personnel responsible for approving the level of airline pilot training told us they were unaware of

the revision to MCAS. Boeing did not communicate to FAA the formal safety risk assessments

related to MCAS until November 2016 and January 2017, more than 4 years into the 5-year

certification process… . Moreover, Boeing’s safety analysis did not assess system-level safety risks

as catastrophic; thus, Boeing designed MCAS to rely on data from a single aircraft sensor rather

than including redundancy, which would have reduced risk.71

Pilot Training

Boeing also sought to avoid the need for extensive pilot training, in particular training in a 737 MAX

flight simulator. Simulation training was expensive and time consuming for airlines, and Boeing feared

it might limit sales. One engineer, who helped design the 737 MAX cockpit and spent 19 years at

Boeing, said the company set a ground rule for engineers: “Limit changes to hopefully avert a

requirement that pilots spend time training in a flight simulator before flying the MAX. Any designs

we created could not drive any new training that required a simulator. That was a first.”72

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Throughout the project, Boeing employees worked to persuade the FAA, their counterparts in other

nations, and customer airlines that MCAS and other changes were minor so as to avoid a requirement

for simulator training for experienced 737 pilots. Forkner repeatedly argued that there were no

significant differences between the 737 MAX and the prior 737 NG. He maintained that computer-

based training (CBT) was sufficient. As he wrote in an email to a customer:73

In their efforts to persuade customers and regulators that simulation training on the 737 MAX wasn’t

necessary and that CBT would be sufficient, Forkner and others referred to using “Jedi mind tricks.”i

On June 7, 2017, Forkner wrote:74

i As defined on the StarWars.com website, a Jedi mind trick is when an experienced Jedi (heroic protagonists of the Star Wars franchise) uses

the Force to implant a suggestion in the minds of those they encounter, encouraging them to comply with the Jedi’s wishes.

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On December 12, 2017, more Jedi references were made. The DGCA referred to the Directorate

General of Civil Aviation in India:75

Boeing proposed and obtained a “Level B” training plan requiring only CBT for pilots already certified

on prior 737s. As described in the Inspector General’s report:

In 2016, FAA and Boeing began certification flight testing to determine the aircraft’s compliance

with FAA’s requirements. In addition, FAA’s Flight Standards Service conducted separate tests

and subsequently approved a training plan proposed by Boeing—known as Level B training—for

737 MAX pilots who were already qualified to fly the Boeing 737-800. This outcome aligned with

Boeing’s overarching goal of achieving a common type ratingii for pilots moving from the NG

series to the MAX and keeping costs down by avoiding simulator training for 737 MAX pilots.

Pilot response to automated MCAS activation was not included in the required training. In March

2017, FAA issued an ATCiii to Boeing for the 737 MAX 8, which began flying passengers later

that year.76

Inside Boeing, provisional FAA approval of Level B training was cause for celebration by at least one

member of the product marketing team, who emailed Mark Forkner and others on August 16, 2016:77

ii A type rating is an endorsement on the pilot certificate indicating that the pilot has completed the required training and testing for a

specific make, type, and/or series of aircraft (for example the Boeing 747-400). From

https://www.oig.dot.gov/sites/default/files/F.A.A.%20Oversight%20of%20Boeing%20737%20MAX%20Certification%20Timeline%20Fin

al%20Report.pdf, accessed December 17, 2020.

iii An Amended Type Certificate (ATC) is issued for aircraft deemed to be “derivatives of already-certificated aircraft.”

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Absent simulator training, 737 MAX pilots were limited to learning about important differences

between the 737 MAX and legacy 737 aircraft through “about an hour’s worth of iPad-based training,”

reported one analyst.78 Some employees believed the training was inadequate and shared their concerns

with one another, as in this February 2018 email exchange:79

Many pilots interviewed in the wake of the accidents, including 737 MAX 8 pilots from Southwest

Airlines, expressed no prior knowledge of MCAS or related procedures required to manage or override

the system should it be activated. “We flat out deserve to know what is in our airplanes,” said a member

of the Allied Pilots Association.80

The Indonesian National Transportation Safety Committee (NTSC), which was investigating the Lion

Air crash, determined that inadequate training and flight manual descriptions were contributing factors

to the accidents. The reported concluded, “The absence of guidance on MCAS or more detailed use of

trim in the flight manuals and in-flight crew training made it more difficult for flight crews to properly

respond.”81

Aftermath

In April 2019, shortly after the crash of Ethiopian Airlines Flight 302, CEO Muilenburg established a

committee at the board level to review the company’s aircraft design and development policies and

processes. The recommendations reportedly included flipping the reporting structure so that senior

engineers would report “primarily” to Boeing’s chief engineer, and “secondarily” to business unit

leaders. The committee also recommended the creation of a new safety group to ensure that the

company’s various efforts had adequate independence and were working together and sharing

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information effectively. The new group would report to senior Boeing leadership, as well as to a new

permanent board committee focused on aerospace safety. And, consistent with the systems approach to

safety, the committee recommended that Boeing re-examine cockpit design and operation to ensure

that new Boeing planes were designed for the next generation of pilots, including those with less

training.82

In May 2019, CNN reported that Boeing proposed that pilots attend a CBT program before they

resumed flying the 737 MAX. The program did not involve hands-on simulator training.83 By January

2020, however, Boeing reversed course and began recommending that pilots undergo simulator training

before they resumed flying the 737 MAX.84 In November, the FAA issued new regulations requiring

special training, including ground and flight training in a full flight simulator for pilots operating the

737 MAX.85

Multiple investigations including criminal inquiries followed the crashes. On October 19, 2019, the

first anniversary of the Lion Air crash, CEO Muilenburg, who had just been removed as chair of

Boeing’s board, was called to testify before a U.S. Senate panel. Families of the passengers were in

attendance, holding up photos of those who had been killed. Asked why Boeing did not ground the 737

MAX after the Lion Air crash, Muilenburg responded, “If we could go back, we would make a different

decision.”86

The following week, Boeing fired Kevin McAllister, CEO of Boeing Commercial Airplanes. Then, in

December 2019, Boeing’s board fired CEO Muilenburg, replacing him with David Calhoun, who had

been named chair of the board following Muilenburg’s removal. Calhoun was a veteran of General

Electric and had served on Boeing’s board since 2009.

FAA Safety Personnel Survey

In August 2020, the media reported on results from a survey of FAA safety personnel. Respondents

indicated they “faced ‘strong’ external pressure from industry.” The survey quoted one employee as

saying that the message was, “Don’t rock the boat with Boeing.” Nearly half of survey respondents

disagreed that the FAA “makes data-driven decisions on safety regardless of external pressure.” Agency

employees stated that they could be “over-powered in meetings with industry.” One employee said: “It

feels like we are showing up to a knife fight with Nerf weapons. It is a challenge to be an equal match

with Boeing in the meetings/conversations.”87

When the results became public, the FAA’s Ali Bahrami, an associate administrator for safety, told his

team he was “troubled by the findings and would work to rebuild trust.”88 Earlier in his career, Bahrami

led the FAA’s Transport Airplane Directorate in Seattle, and, reportedly, pursued “the FAA’s new

business mantra with gusto.” When FAA “specialists raised technical issues, they’d be told to stand

down—often by Bahrami himself.”89 Under pressure from many in Congress, victims’ families, FAA

staff, and others, Bahrami announced his retirement in June 2021.

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Financial and Reputational Damage

Estimates of the financial and reputational damage to Boeing, its shareholders, employees, suppliers,

and the U.S. and global economy varied. One concluded that Boeing faced over $21 billion in direct

costs and $67 billion in lost sales of 1,200 aircraft. Direct costs included:

• $8.6 billion in compensation to customers for having their aircraft grounded;

• $5 billion for unusual costs of production;

• $6.3 billion for increased costs of the 737 MAX program;

• $600 million for aircraft storage, pilot training, and software updates; and,

• An estimated $500 million in settlements to victims’ families.90

There were also indirect costs, including the costs of organizational changes, increased regulatory

oversight, and higher capital costs due to downgrades in Boeing’s debt ratings and drops in its stock

price. Both Boeing and Airbus experienced sharp declines in their share prices once COVID-19 hit.

Airbus’s stock began to recover as people started to travel again in early 2021. But by mid August 2022,

Boeing’s shares were 52% below their level just before the first 737 MAX crash. Airbus shares were

20% higher (Exhibit 12).

Conclusion

By mid 2022, air traffic was rebounding and the outlook for the aircraft industry had turned up. Yet

Boeing, the industry, the U.S., and other nations continued to face profound and challenging questions:

How could the tragedies have been avoided? What prevented engineers and other Boeing employees

from making their voices heard to managers who could have changed the course of the 737 MAX’s

design and development? Why did so many otherwise responsible employees and managers fail to stand

up for quality and safety under the pressure to hit aggressive schedule and cost targets? Could Boeing,

and other firms, be trusted to self-regulate? What reforms were needed at the FAA and other agencies

to assure their independence and effectiveness? What ongoing oversight of the industry—and the

regulators—would be needed?

Meanwhile, the families of the 346 victims continued to grieve.

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Exhibit 1 U.S. General Aviation Safety Data – 1975 to 2018

Note: Accidents on foreign soil and in foreign waters are excluded.

Source: Bureau of Transportation Statistics, “U.S. General Aviation Safety Data,” https://www.bts.gov/content/U.S.-general-

aviationa-safety-data.

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Exhibit 2 Commercial Aircraft Orders (top) and Deliveries (bottom) for Boeing and Airbus*

*Note: Data through 2019 (before COVID-19 pandemic impact).

Source: Wikipedia, https://en.wikipedia.org/wiki/Competition_between_Airbus_and_Boeing#cite_note-Time_Period_Reports-

107, accessed 24 October 2020. See also https://www.statista.com/statistics/264493/airbus-worldwide-aircraft-deliveries/ and

https://www.statista.com/statistics/273968/number-of-delivered-aircraft-by-boeing/. All cite Boeing and Airbus as the underlying

sources for the data.

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Exhibit 3 Boeing 737 Family of Aircraft – 1967 to 2017

Source: U.S. Department of Transportation, Office of Inspector General, “Timeline of Activities Leading to the Certification of

the Boeing 737 MAX 8 Aircraft and Actions Taken After the October 2018 Lion Air Accident,”

https://www.oig.dot.gov/sites/default/files/F.A.A.%20Oversight%20of%20Boeing%20737%20MAX%20Certification%20Timeline

%20Final%20Report.pdf.

Exhibit 4 Boeing Aircraft Pricing Data

Source: Statista, “Airbus and Boeing,” https://www.statista.com/statistics/273941/prices-of-boeing-aircraft-by-type/, accessed

November 9, 2022. Originally sourced from www.boeing.com.

Average prices for Boeing aircraft as of March

2022, by type (in million U.S. dollars)

737-700 89.10

737 MAX 7 99.70

737-800 106.10

737-900ER 112.60

737 MAX 8 121.60

737 MAX 200 124.80

737 MAX 9 128.90

737 MAX 10 134.90

767-300ER 217.90

767-300 Freighter 220.30

787-8 248.30

787-9 292.50

777-200ER 306.60

787-10 338.40

777-200LR 346.90

777 Freighter 352.30

777-300ER 375.50

777-8 410.20

747-8 418.40

747-8 Freighter 419.20

777-9 442.20

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Exhibit 5 Boeing Commercial Airplanes “Go Ahead” and “Initial Delivery” Schedules

Source: Boeing Company 2019 Annual Report.

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Exhibit 6 Timeline of Significant Events for the Certification of the Boeing 737 MAX 8

Source: U.S. Department of Transportation, Office of Inspector General, “Timeline of Activities Leading to the Certification of

the Boeing 737 MAX 8 Aircraft and Actions Taken After the October 2018 Lion Air Accident,” p. 11.

https://www.oig.dot.gov/sites/default/files/F.A.A.%20Oversight%20of%20Boeing%20737%20MAX%20Certification%20Timeline

%20Final%20Report.pdf.

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Exhibit 7 Boeing and Airbus Revenue and Profit, 1995–2021

Revenue

Net Income

Source: Orbis.

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Exhibit 8 Cumulative Five-Year Returns

Source: Boeing 2018 Annual Report.

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Exhibit 9 737 NG Engine (left) versus the 737 MAX Engine (right)

Source: U.S. Department of Transportation Inspector General Report,

https://www.oig.dot.gov/sites/default/files/FAA%20Oversight%20of%20Boeing%20737%20MAX%20Certification%20Timeline%20Final%20Report.pdf, p. 6.

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Exhibit 10 Overview of MCAS

Source: U.S. Department of Transportation Inspector General Report,

https://www.oig.dot.gov/sites/default/files/FAA%20Oversight%20of%20Boeing%20737%20MAX%20Certification%20Timeline%20Final%20Report.pdf, p. 7.

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Exhibit 11 AOA Disagree Alert and AOA Indicator

Source: U.S. Department of Transportation Inspector General Report,

https://www.oig.dot.gov/sites/default/files/FAA%20Oversight%20of%20Boeing%20737%20MAX%20Certification%20Timeline%20Final%20Report.pdf, p. 28.

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Exhibit 12 Boeing and Airbus Stock Prices

Index: Share prices on 10/22/2018 = 100.

Source: Data from Yahoo Finance. Weekly closing price, adjusted for splits, dividends, and capital gains distributions.

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Endnotes

1 Megan Specia, “What We Know About the Lion Air Flight 610 Crash,” The New York Times

(https://www.nytimes.com/2018/11/09/world/asia/air-lion-crash-610.html, accessed July 3, 2020).

2 Joint Authorities Technical Review, “Boeing 737 Max Flight Control System: Observations, Findings, and

Recommendations,” October 11, 2019

(https://www.F.A.A.gov/news/media/attachments/Final_JATR_Submittal_to_F.A.A._Oct_2019.pdf, accessed

September 15, 2020).

3 https://boeing.mediaroom.com/news-releases-statements?item=130336.

4 U.S. Department of Transportation, Office of Inspector General, “Timeline of Activities Leading to the

Certification of the Boeing 737 MAX 8 Aircraft and Actions Taken After the October 2018 Lion Air

Accident,” June 29, 2020

(https://www.oig.dot.gov/sites/default/files/F.A.A.%20Oversight%20of%20Boeing%20737%20MAX%20Ce

rtification%20Timeline%20Final%20Report.pdf, accessed December 17, 2020).

5 Dennis Muilenburg interview on Fox Business, November 13, 2018.

https://www.foxbusiness.com/business-leaders/boeing-ceo-our-airplanes-are-safe, accessed August 15, 2022.

6 Peter Robison, Flying Blind: The 737 Max Tragedy and the Fall of Boeing. New York: Doubleday, 2021, p.

5.

7 Ibid, p. 194.

8 Hadra Ahmed, Nori Hadra Ahmed, et. al., “Ethiopian Airlines Plane Is the 2nd Boeing Max 8 to Crash in

Months,” The New York Times, March 10, 2019

(https://www.nytimes.com/2019/03/10/world/africa/ethiopian-airlines-plane-crash.html, accessed December

15, 2020).

9 Ibid.

10 Dominic Gates, “How Much Was Pilot Error a Factor in the Boeing 737 MAX Crashes?”, The Seattle

Times, May 15, 2019 (https://www.seattletimes.com/business/boeing-aerospace/how-much-was-pilot-error-a-

factor-in-the-boeing-737-max-crashes/, accessed November 10, 2020).

11 U.S. Department of Transportation Office of Inspector General, “Weaknesses in FAA’s Certification and

Delegation Processes Hindered Its Oversight of the 737 MAX 8,” February 23, 2021

(https://www.oig.dot.gov/sites/default/files/F.A.A.%20Certification%20of%20737%20MAX%20Boeing%20

II%20Final%20Report%5E2-23-2021.pdf, accessed August 15, 2022).

12 Dominic Gates, “Boeing Wins Zero New Orders, Delivers Few Jets and Sees 737 MAX Backlog Shrink,”

The Seattle Times, November 10, 2020 (https://www.seattletimes.com/business/boeing-aerospace/boeing-

wins-zero-new-orders-delivers-few-jets-and-loses-more-737-maxs/, accessed December 15, 2020).

13 FAA Updates on Boeing 737 MAX, https://www.F.A.A.gov/news/updates/?newsId=93206, accessed

November 18, 2020.

BOEING’S 737 MAX 8 DISASTERS John Sterman and James Quinn

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14 Boeing. “Enter Air to Purchase up to Four Boeing 737-8 Jets (https://boeing.mediaroom.com/news-

releases-statements?item=130724, August 19, 2020. Accessed August 15, 2022).

15 International Civil Aviation Organization, https://www.icao.int/annual-report-

2019/Documents/ARC_2019_Air%20Transport%20Statistics.pdf#search=2019%20air%20transport%20statis

tical%20results, accessed August 18, 2022.

16 International Civil Aviation Organization, “State of Air Transportation in 2018 and the Role of Air

Transport Connectivity,” Istanbul, Turkey, July 10, 2019 (https://www.icao.int/Meetings/aviation-data-

analysis-

seminar/Presentations/State%20of%20Air%20Transport%20in%202018%20and%20the%20Role%20of%20

Air%20Transport%20Connectivity.pdf#search=Presentation%20of%202018%20Air%20Transport%20Statist

ical%20Results%20page, accessed December 15, 2020).

17 Boeing Statistical Summary of Commercial Jet Airplane Accidents, Worldwide Operations, 1959–2018

(https://www.boeing.com/resources/boeingdotcom/company/about_bca/pdf/statsum.pdf, accessed July 27,

2020).

18 Federal Aviation Administration, “Human Error and Commercial Aviation Accidents: A Comprehensive,

Fine-Grained Analysis Using HFACS,” July 2006

(https://www.F.A.A.gov/data_research/research/med_humanfacs/oamtechreports/2000s/media/200618.pdf,

accessed July 23, 2020).

19 Nancy Leveson, Engineering a Safer World: Systems Thinking Applied to Safety. Cambridge, MA: The

MIT Press, 2016.

20 James Reason, “Human error: models and management.” BMJ, 18 March 2000, 320(7232): 768-770. doi:

10.1136/bmj.320.7237.768https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1117770/, accessed August 15,

2022.

21 John Newhouse, Boeing versus Airbus, First Vintage Books, January 2008, p.3.

22 Fortune Magazine, “Fortune 500 Database,”

https://archive.fortune.com/magazines/fortune/fortune500_archive/full/1990/.

23 Ibid.

24 Ibid.

25 Boeing, “Brief History and Chronology,” https://www.boeing.com/history/, accessed July 20, 2020.

26 Leon Grunberg and Sarah Moore, Emerging from Turbulence, Rowman & Littlefield, 2016, p. 2.

27 Ibid. p. 2.

28 Ibid, pp. 2-3.

BOEING’S 737 MAX 8 DISASTERS John Sterman and James Quinn

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29 Patricia Callahan, “So Why Does Harry Stonecipher Think He Can Turn around Boeing?,” The Chicago

Tribune, February 29, 2004 (https://www.chicagotribune.com/chi-0402290256feb29-story.html, accessed

December 15, 2020).

30 Brian Knowlton, “Boeing to Buy McDonnell Douglas,” The New York Times, December 16, 1996

(https://www.nytimes.com/1996/12/16/news/boeing-to-buy-mcdonnell-douglas.html, accessed December 15,

2020).

31 Edward S. Greenberg, Leon Grunberg, Sarah Moore, Patricia B. Sikora, Turbulence, Yale University Press,

2010, pp. 48-53.

32 Edward S. Greenberg, Leon Grunberg, Sarah Moore, Patricia B. Sikora, Turbulence, Yale University

Press, 2010, p. 14.

33 John Newhouse, Boeing versus Airbus, First Vintage Books, January 2008, p. 13.

34 Leon Grunberg and Sarah Moore, Emerging from Turbulence, Rowman & Littlefield, 2016, pp. 34-35.

35 Peter Robison, Flying Blind: The 737 Max Tragedy and the Fall of Boeing. New York: Doubleday, 2021,

pp. 142-143.

36 Leon Grunberg and Sarah Moore, Emerging from Turbulence, Rowman & Littlefield, 2016, pp. 42-43.

37 John Newhouse, Boeing versus Airbus, First Vintage Books, January 2008, p. 7.

38 Ibid.

39 Ibid, prologue, p. x.

40 Statista, “Airbus and Boeing,” Originally sourced from Boeing Company Website, www.boeing.com.

41 Boeing 2017 Annual Report, pp. 3-4

(https://s2.q4cdn.com/661678649/files/doc_financials/annual/2017/2017-Annual-Report.pdf, accessed

August 4, 2020).

42 Boeing 2018 Annual Report, p. 129

(https://s2.q4cdn.com/661678649/files/doc_financials/annual/2019/Boeing-2018AR-Final.pdf, accessed

August 4, 2020).

43 Boeing 2017 Annual Report, p. 3 (https://s2.q4cdn.com/661678649/files/doc_financials/annual/2017/2017-

Annual-Report.pdf, accessed August 4, 2020).

44 David Gelles, Natalie Kitroeff, Jack Nicas, and Rebecca R. Ruiz, “Boeing was ‘Go, Go, Go’ to beat Airbus

with the 737 Max, The New York Times, March 23, 2019

(https://www.nytimes.com/2019/03/23/business/boeing-737-max-crash.html, accessed August 20, 2020).

45 Steve Wilhelm, “Boeing’s McNerney: Just Say No to Betting the Company on Technological Leaps,”

Puget Sound Business Journal, May 21, 2014

BOEING’S 737 MAX 8 DISASTERS John Sterman and James Quinn

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(https://www.bizjournals.com/seattle/news/2014/05/21/boeings-mcnerney-just-say-no-to-betting-the.html,

accessed October 4, 2022).

46 David Gelles, Natalie Kitroeff, Jack Nicas, and Rebecca R. Ruiz, “Boeing was ‘Go, Go, Go’ to beat Airbus

with the 737 Max, The New York Times, March 23, 2019

(https://www.nytimes.com/2019/03/23/business/boeing-737-max-crash.html, accessed August 20, 2020).

47 Ibid.

48 Ibid.

49 Peter Robison, Flying Blind: The 737 Max Tragedy and the Fall of Boeing. New York: Doubleday, 2021,

p. 135.

50 David Gelles, Natalie Kitroeff, Jack Nicas, and Rebecca R. Ruiz, “Boeing was ‘Go, Go, Go’ to beat Airbus

with the 737 Max, The New York Times, March 23, 2019

(https://www.nytimes.com/2019/03/23/business/boeing-737-max-crash.html, accessed August 20, 2020).

51 Ibid.

52 Peter Robison, Flying Blind: The 737 Max Tragedy and the Fall of Boeing. New York: Doubleday, 2021,

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53 https://int.nyt.com/data/documenthelper/6653-internal-boeing-

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