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Documentary 101: PBS Frontline – Boeing’s Fatal Flaw 2021

787 Dreamliner Boeing

On 14th September 2021, PBS Frontline ran an excellent documentary on Boeing’s series of shocking mishandling & process failure in the manufacturing of the new 737-Max passenger plane. The trigger point was the introduction of the new Airbus A320neo and the delay of Boeing’s next model, the 787 Dreamliner. Image source: PRNewsfoto/Boeing

There was tremendous pressure to bring the new plane into the market in time to counter Airbus’ A320Neo plane. In the end, a software glitch caused 2 major accidents that saw 346 passengers & crew died, Boeing & airlines suffered substantial financial losses due to glitch & grounded planes and caused the chairman & CEO, Dennis Muilenburg his job.

Read These First:-

In addition to the financial and reputation implications, criminal charges have now been registered as well:-

Federal prosecutors are preparing to indict a former Boeing test pilot suspected of misleading aviation regulators over the safety issues blamed for two fatal 737 MAX crashes.

Mark Forkner was Boeing’s 737 MAX chief technical pilot during the aircraft’s development, and was the lead contact between the aviation giant and the Federal Aviation Administration over how pilots should be trained to fly the planes, the Journal said.

According to documents published in early 2020, Forkner withheld details about the planes’ faulty flight handling system known as the Maneuvering Characteristics Augmentation System, or MCAS — later blamed for both crashes — from regulators.

(Source: CBS News)

The Documentary

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It is a well put documentary with interviews with the victims, ex-staff of Boeing, the FAA, the Congress and the NYT reporters who pursued the inside story.

Airbus A320neo Boeing

There is always competition between US-based Boeing which was founded in 1916 and the newer European based Airbus which was founded in 1970. Each company has products that compete directly with each other except perhaps the huge A380. Other than the intensive fight between Boeing 737 and Airbus’ A320, the other intense competition is between Boeing 777 and Airbus’ A340 aircrafts. Image source: Russian Aviation

Airbus A320Neo Threat

The fast-tracking of the Boeing 737 Max aircraft production was triggered by the Airbus’introduction of a more fuel-efficient A320neo in 2010 which itself was 20% more fuel-efficient than their earlier A320 models.

Airbus originally had small, triangular wingtips on the A320. These worked functionally but actually proved to increase drag. As a result, Airbus drew inspiration from Boeing’s blended winglet designs.

This led to the development of a larger, curved wingtip called a ‘sharklet.’ This allowed Airbus to significantly increase fuel efficiency, by a factor of approximately 7%. (Note: Airbus A320ceo aircraft are fitted with sharklets)

It also goes without saying that a major improvement is the different engines present on the A320neo. The new engine option is more fuel-efficient, giving the aircraft a greater range. It is also noticeably quieter than the older variant, both externally and in terms of what can be heard by passengers within the cabin.

The cabin has seen several improvements, both technologically and ergonomically. These features include better pressurization, greater luggage space, and noise reduction systems. Passengers can also enjoy LED lighting and a modern seating design for greater comfort

(Source: Simple Flying)

Boeing’s nearest aircraft that was competing against A320neo was their 737-800 series which is the 3rd generation of 737 which was first introduced in the 1960s. The 737-800 which was introduced in the late 1990s was falling short against the newer A320neo – it only carries 160 passengers against neo’s 165, it carries less fuel of 26,022 litres against neo’s 29,659 litres and its maximum range is 5,570 km which was shorter than neo’s 6,500 km.

However based on the range over fuel, for every km, A320neo aircraft burns 0.22 litres of fuel whilst 737-800 burns 0.21 litres of fuel – it is hardly a major difference.

The same has been noticed:-

The two aircraft under consideration here are, at first glance, very similar. However, there are some fundamental differences when it comes to passenger comfort. The Airbus A320 has a wider cabin than the Boeing 737.

It’s only seven inches but can make all the difference to the ride comfort. For passengers, this often means a slightly wider seat, which is always welcome, even on short-haul

(Source: Simple Flying)

And here is another view on the differences:-

The numbers tell us that the A320 “Classic” burns about 6% less fuel than the B737-800W, and the NEO burns about 15% less fuel. Now, the payload is short twelve seats (about 1200kg).

Translating fuel costs into fuel weight (3.88l/gal, .82kg/l), the A320 Classic has a 200kg advantage over the -800W. Correcting for the additional payload, the advantage shrinks to 120-150kg in favour of the A320 Classic.

Not sure about the maintenance costs, but when it comes to fuel efficiency, the current A320 already beats the -800W. Assume a rise of the fuel costs of 50% and the NEO will be the winner in CASM, too, even with a lower seat count.

By the way: 158 seats look like 2-class, so the revenue potential of the 150-seat A320 might be better than that of the 170-seat B737-800.

(Source: Lee Ham News)

Boeing’s other model, the 777 series was a good plane and I personally love the cabin & features (compared to Airbus) but it was designed more for the long haul than a short one and it burns more fuel which will not be feasible for low cost, budget short-haul airlines. The newer 787 Dreamliner is still in development and will not be ready in time to challenge A320neo significantly.

So, Boeing decided to enhance their 3rd generation 737 series to the next generation called 737 Max so as not to lose out to Airbus’ A320neo.

737 Max Boeing

Boeing 737 Max is not a new design but it is based on an older but winning design that has sold quite well in the past. MCAS is a new system that had to be implemented to counter stability due to the larger engines. However, budget airlines still prefer new models that can save more fuel whilst be able to carry more passengers. Image source: The Seattle Times

Boeing 737 Max vs Airbus A320neo

This is a very good analysis between the various ranges of 737 Max against the A320 neo:-

Airbus A319neo vs. Boeing 737 MAX 7

Looking at passengers, we can see that the A319neo carries more than its rival, the Boeing 737 MAX. However, there are only seven passengers more. If it was a short flight of only $100 per ticket, that’s only $700 extra revenue.

Likewise, the 737 can only fly an additional 100 NM than the Airbus, which, without going into details about fuel efficiency, may imply better operational costs. We are not convinced that a small number of extra passengers (seven) would beat out the better range of the 737 MAX 7.

Winner: Boeing 737 MAX 7

Airbus A321neo vs. 737 MAX 10

We will put the A321neo up against the 737 MAX 10 since the latter has the closest amount of seats to the Airbus model. Altogether, the A321neo has a maximum capacity of 240, which trumps the MAX 10’s offering.

The plane also has a range that’s 700 NM greater than its rival. Therefore, a company that’s in the market for a 200+ capacity narrowbody may likely prefer to go for Airbus’ solution.

Winner: Airbus A321neo

Airbus A320neo vs. Boeing 737 MAX 8/9

With a top-down perspective, we can see that the Airbus A320neo carries two more passengers than the 737 MAX 9, which in turn flies 50 NM more than the Airbus model.

This makes a comparison on range or passengers almost inconsequential and really showcases just how tight the competition is. Looking at the specifics, we can see that the Boeing 737 MAX beats the A320 with a higher max payload (46,040 lb vs 44,100 lb) and a higher thrust power.

The 737 MAX 9 can also be reconfigured into a super-dense 220 seater variant (or in the case of the MAX 8, a 200 seater which will be the new Ryanair variant). The 737 MAX 8 can also carry more cargo than the Airbus A320, meaning more revenue for the airline. In summary, this means more lifting power, more room, and more flexibility for airlines.

Winner: 737 MAX 8/9

(Source: Simple Flying)

MCAS Boeing Maneuvering Characteristics Augmentation System 737 Max

Image source: BBC

The Notorious MCAS

Maneuvering Characteristics Augmentation System (MCAS) which is a flight stabilisation system was first developed in the 1960s for the Boeing 707 which later was continued as the KC-135 tanker which provides air to air refuelling and which is still in service todate.

The MCAS design parameters originally envisioned automated corrective actions to be taken in cases of high AoA and G-forces beyond normal flight conditions. Test pilots routinely push aircraft to such extremes, as the FAA requires aeroplanes to perform as expected.

(Source: Wikipedia)

Based on the information provided by Boeing, the MCAS is activated only when 3 conditions exist at the same time:-

  • The pilot is flying the aeroplane manually.
  • The aeroplane nose approaches a higher-than-usual angle.
  • The pilot has the wing flaps up.

An enhanced MCAS was installed in 737 Max when it was found that the plane was not flying smoothly due to its large new engines. Boeing in the end decided that they will use software instead of a change of aerodynamics as a cheaper and faster solution. This MCAS has now been identified as the cause of 2 fatal accidents:-

In flights ET 302 and JT 610, investigators determined that MCAS was triggered by falsely high angle of attack (AoA) inputs, as if the plane had pitched up excessively.

On both flights, shortly after takeoff, MCAS repeatedly actuated the horizontal stabilizer trim motor to push down the airplane nose. Satellite data for the flights showed that the planes struggled to gain altitude.

Pilots reported difficulty controlling the airplane and asked to return to the airport

(Source: Wikipedia)

Boeing reported the same:-

Prior to being enhanced, MCAS relied on information from a single Angle of Attack (AOA) sensor to monitor the angle of the airplane.

In the two accidents, a single AOA sensor gave incorrect information to MCAS, which caused it to activate. In both cases, MCAS engaged repeatedly when the sensor continued to incorrectly report a high AOA.

(Source: Boeing)

Boeing had gone back and redesigned and retested the MCAS with new enhancements to avoid similar accidents involving MCAS:-

MCAS now contains multiple enhanced protections:

  • Measurements from two Angle of Attack (AOA) sensors will be compared.
  • Each sensor will submit its own data to the airplane’s flight control computer.
  • MCAS will only be activated if both sensors agree.
  • MCAS will only be activated once.
  • MCAS will never override the pilot’s ability to control the airplane using the control column alone.

(Source: Boeing)

Boeing 737 Max

It is tragic that 346 people had died due to a software glitch that was discovered during testing but was not highlighted to others due to the rush to get the plane certified for sale. Image source: Channel NewsAsia

Indian Software Developers

Interestingly soon after the tragic accidents and when the issue with MCAS was found, the software glitch was linked with poor, inexperienced software developers from India:-

It remains the mystery at the heart of Boeing Co.’s 737 Max crisis: how a company renowned for meticulous design made seemingly basic software mistakes leading to a pair of deadly crashes. Longtime Boeing engineers say the effort was complicated by a push to outsource work to lower-paid contractors.

Increasingly, the iconic American planemaker and its subcontractors have relied on temporary workers making as little as $9 an hour to develop and test software, often from countries lacking a deep background in aerospace — notably India.

The coders from HCL were typically designing to specifications set by Boeing. Still, “it was controversial because it was far less efficient than Boeing engineers just writing the code,” Rabin said. Frequently, he recalled, “it took many rounds going back and forth because the code was not done correctly.”

(Source: The Print)

Frankly speaking, this was something that was hard to believe considering India has some of the best software houses and has well-established processes, best practices and high-level standards in its software lifecycle. And this was echoed by the same in India:-

The implications in the report didn’t sit well with engineers in India, with critics quick to point out that India has many aerospace engineers that are extremely competent. Not to mention Boeing has said it didn’t tap engineers from HCL or Cyient to develop the Maneuvering Characteristics Augmentation System, which has been blamed for the October Lion Air crash and the March Ethiopian Airlines wreck.

HCL said it wasn’t associated with the issues with the 737 Max and Cyient called the news article wrong. It said as a company it taps engineers from the best talent pools available, including 1,000 engineers hired in the U.S. Cyient said its engineers are veterans working with aerospace original equipment manufacturers and system providers for several years.

(Source: Interesting Engineering)

In September 2020, after more than a year of investigations by federal agencies and the US Congress, the following report was released:-

A 245-page report issued Wednesday provides the most scathing account so far of the miscalculations that led to 346 deaths, the grounding of Boeing’s best-selling jet and billions of dollars in losses for the manufacturing giant.

The report — the result of five investigative hearings, a review of about 600,000 pages of documents, interviews with top Boeing and FAA officials and information provided by whistle-blowers — makes the case for broad changes in the FAA’s oversight of the aircraft industry.

The conclusions were drawn by the majority staff under committee Chairman Peter DeFazio. The report cites five main reasons for the crashes:-

  • Pressures to update the 737’s design swiftly and inexpensively
  • Faulty assumptions about the design and performance of pilots
  • What the report called a “culture of concealment” by Boeing
  • Inherent conflicts of interest in the system that deputizes Boeing employees to act on behalf of the government
  • The company’s sway over top FAA managers

(Source: Time)

This is to say that the software glitch itself was not the cause of the tragic accidents but also a series of cascading process failures that caused deaths and financial loss.

A320neo 737 Max Boeing Aeroplane Airbus

As of todate, Neo commands 60% of the overall order with 4414 planes (BLUE) and 737 Max with 40% at 2931 planes (RED). Image source: PDX Light

Final Say

In Malaysia, the largest operator of A320neo is Air Asia with 30 A320neo and 2 A321neo in its fleet. They already are operating 65 A320-200 before this and they ordered more than 300 A320neo family planes for future expansion. However, this was before the pandemic which basically shut down flights all over the world. They do not operate any 737 Max but they have the older 737-200 and 737-300 in operations which will be replaced by Airbus planes in future.

The national carrier, Malaysia Airlines (MAS had ordered 15 Boeing 737 Max 8 and 10 Boeing 737 Max 10 for future operations but only expect to receive them by 2024 which means the MCAS fault would have been fixed and pilots trained. They still operating 47 737-800 in their fleet.

Certainly, there would be some hesitance on the future Boeing sales of 737 Max given the fact that 346 lives have been lost due to a software glitch that was not fixed due to pressure to bring the new model to sale. Additional pilot training was not done to shorten the lifecycle of manufacturing. It is a lesson to be learned, not only for the airline manufacturing but any industries that have development – testing – deployment cycle and failures will have financial or worse, tragic outcomes.

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