Boeing, Boeing - by Babelfish

737 Max, a layperson reflection and IMHO.

First, there is a terrific YouTube channel, Mentour Pilot, that I watch, which is hosted by a current European 737 captain. It is not ‘sound bite video’ and is an investment in time but it is thorough and he is a very good presenter. I will try to link in some of his videos.

I wrote this piece for Facebook, a few weeks back. I thought it might be a useful waypoint for the journey the commercial aircraft world is going on, for the rest of this year.

The first Boeing success in passenger jets was the 707, in the late 50s. That was followed by the 727, once ubiquitous as a short haul airliner. The 737 followed in the late 60s. The point here is that all three jets had essentially the same cross section. The 737 had the same engines as the 727 but only two rather than three. They were models of the legendary JT8D, much longer than wide. This allowed for shorter landing gear.

The 737 is the most popular airliner in history. There is one unique feature involving the landing gear. The main gear wheels do not have an outer cover when retracted. The tires are exposed, just like a P-40 Warhawk from WW2. This is due to a design decision that was driven by a predicted need to operate from small airports with few resources. It was done to keep the jet low while on the ground, for loading and maintenance,and it did not leave room for the typical fuselage bulge (fairing) for wheel covers.

So far, 1950s cross section and low to the ground design, assisted by a jet engine that did not have a big fan in front.

The 737-400 got big fan engines. The nacelles (engine covers) are actually flat on the bottom, rather the normal circular shape, to keep the same landing gear and low profile. It works but looks a tad odd. It was a first of other compromises to come.

By 1984, Airbus had designed and began selling the main competitor to the 737, the A319/A320/A321 series. Designed later, from a clean sheet, the fuselage profile is wider. (I prefer this plane as the seats are side to side roomier.) Jet Blue is a big customer. There is a higher stance and the wheels are fully enclosed when they retract. Unlike the 737, there was room for larger, more efficient engines without resorting to tricks with the nacelles or engine placement. The cockpit is more modern. They are outselling the 737, which also still continued to sell very well. The 737 is considered to be at the end of its possible development. The A320 series is clearly not. After several generations of both planes, each sporting incremental improvements in engines and avionics, a new emphasis on even larger, more fuel efficient engines arrived.

As a side note, we enthusiasts kept wondering when or if Boeing would replace the 737 with an airplane even more modern than the Airbus competitors. Like wider, with an up to date cockpit and avionics and lighter structures like the fabulous 777 and 787. The discussion was that the Max was one iteration too much. But they sell all they can make without the unbelievable investment a new airplane would take. It is found money, living on an investment made in the late 60s. Important to understand that the 737 is a huge cash cow, funding much of the rest of the commercial division, including the development of new aircraft. Any drop in sales is a serious matter. The A320 series has the same status with Airbus.

The YouTube channel,  Mentour Pilot, explains the technicality of the changes made to the 737 to get to the Max version and what the MCAS system is. I will try to include a link below. The Max has new engines that are so much larger than the original JT8D, that they had to move them forward and upward to make them fit. It changed the center of gravity and gave a pronounced pitch up dynamic when the now more powerful thrust was applied. Excessive pitch up can be very bad, like get into a low altitude stall and crash the jet bad. At too high an nose angle the wings lose lift. No lift, no flying, just a plane dropping from the sky. And the pilot asks for that increased thrust at take off and climb, down low with little altitude to work with.

A serious development factor with the Max was to get pilots to be able to transfer from the prior generations of 737 to the Max with as minimal a training program as possible. A very big selling point. The competitor jet is more comfortable (IMO), a more modern design so you need a competitive edge. The MCAS system was the key. It allegedly made the Max fly like the older generations, preventing the higher thrust from causing a uncontrollable pitch up. One pilot stated that his transition training was 60 minutes on an IPad. Pilots stated they were not aware it was even there, running the whole time. There is no way to “turn it off”.

Things get real technical at this point but the basic system relies on a correct read from a single pitch sensor or AOA (angle of attack) sensor. The jet has two, looking like small vanes on either side of the fuselage, just below the cockpit. Focus on the fact that the safest version of MCAS, using both sensors rather than one, cost more money. And so many airlines did not order it.

Now the story starts going very badly. If the one sensor the basic system is looking at goes bad, MCAS does not know the actual nose pitch of the jet and starts to take over trying to fix a problem that isn’t there. The pilots can not turn it off. As stated, most didn’t even know it was there. Without the sensor working properly it is going to do the wrong things. In Lion Air, the sensor and system was repeatedly found faulty on prior flights. In the Ethiopian crash, there is evidence that a bird strike knocked it off the aircraft. The only thing the pilots can do is turn off the electric motor that controls the horizontal stabilizer (sets pitch or nose angle) and crank the stabilizer by hand. Again, watch the Mentour Pilot video on this.

There is evidence that pilots were reporting issues prior to the Lion Air crash and they absolutely confronted Boeing after it. I have to tell you that this reminds me of the moment after the Challenger accident when we were informed of the outcome of the Rodgers Report and there was undeniable evidence that appropriately placed people knew the infamous O-Rings were leaking all along and were worse as the temperature got colder. We were gutted.

With the Shuttle, IMO, people were allowed to redefine their jobs as “making it  fly”, not making it fly safely. The word safely got crushed out. I believe Boeing had all the evidence needed to stop this as early as a year ago, if not further back. Corporate cultures, NASA included, create lethal environments for people who scream STOP! See the Columbia accident for a repeat at NASA. It was bad enough that action wasn’t taken before the Lion Air accident. I fully believe it’s absolutely inexcusable after.

It is not a silly question to ask if Boeing Commercial Aircraft will survive this event. No Lockheed, Douglas or Convair airliners are being manufactured these days. One thing money can’t buy is trust. Airlines are cancelling 737 orders. Airbus is selling large numbers of the A320 family and has the financial backing of European countries. The A380 failure (enormous investment and far too few sales) could have taken out a company but not  a group of nations. China has a need for some 7,000 regional planes. They are working hard to develop and make their own competent aircraft and to compete internationally. They are a nation, not a private company that has to make a profit.

I (layperson that I am), do not think Boeing Commercial Aircraft will disappear but it may lose its peer status with Airbus. They will fix the Max. That being said, there are serious issues in resolving the correct training to give to pilots. The sales edge of very little training is gone. There are reports that 737 Max simulators, a very big deal in training pilots, need faults corrected in their software. Getting this model back to flying was thought to be a matter of a month or two. Now August may be the earliest qnd the Paris Air Show, where many new sales are usually announced, is nearly at hand.

Boeing has been trying to make a decision on the all new 797, which would replace 757s and 767s now ageing out of usefulness. The market is estimated at 4,000 aircraft on a global basis. Airbus is pitching an A321 variant as the right answer. Their more modern aircraft, the A321, still has room for development. Boeing has to fund, develop, and launch the 797 aircraft. At that point they will be still left with no replacement for the 737.

There is a saying that a commercial aircraft firm bets the company when developing a new airliner. Did Boeing bet the company on not developing a 737 replacement? It looks like we may find out in the next few years.

https://www.youtube.com/watch?v=TlinocVHpzk

https://www.youtube.com/watch?v=CD0JabYjF3A

https://www.youtube.com/watch?v=SoDMTwJwHyI

Comments

[JohnH]

How does Embraer factor into the mix? I flew a brand new one on United from Houston to central Mexico, probably an E-175-s. As a passenger, I was impressed. It struck me that Embraer was now getting into Boeing's cash cow business.

[BraveNewWorld]

After the ban on technology to China there is zero chance that China will buy Boeing and become the next Iran. They might buy Airbus short term if the US doesn't stop them but China and Russia have already reached an agreement to joint produce airliners.

Cold war 2.0 marches on.

[BabelFish]

John, Boeing saw that one coming and purchased controlling interest in Embraer's commercial airline unit. It was approved this year.

Airbus countered by buying Bombardier's A220 program.

I like Embraer jets. I flew on a lot of turboprops and remember the improvement when the Embraer and Bombardier jets replaced them.

[BabelFish]

Not thinking the Airbus purchase would ever happen. Airbus has significant national ownership. Fiat was trying to merge with Renault and the French government just stopped that.

[Barbara Ann]

I've not followed this closely, but ever since I discovered that MCAS relied on a single sensor (in the cheaper version) I have wondered about the FAA's role in this. How in God's name did an aircraft with such an obviously dangerous lack of redundancy in a critical system get certified?

[BabelFish]

Yes. Another post all by itself. Still digging at that but it appears the FAA agreed with Boeing that MCAS would not have to be published in the pilot manuals, or actions were just about to that effect.

I made the comment that this would all become a great business class in how not to do something and how exactly not to respond to a disaster that it caused.

[VietnamVet]

This is an excellent article. Since I was born and raised in a Boeing family; I’ve been following this the best I can. To get EU and China’s recertification the Max’s fix will have to be comprehensive and make the plane safe to fly. Sometime next year? This all started when Boeing merged with McDonnell Douglas in 1997 and GE’s Jack Welch followers made increasing shareholder value and corporate suite bonuses the priority at Boeing. What killed 346 people was deregulation and the politicians who cut FAA funding and allowed Boeing to self-certify the safety of their aircraft. Like what already happened to the Rust Belt, taxes will continue to be cut and money transferred to the global rich until the aircraft industry in North America withers away. The next generation single aisle airliner will be assembled in China. Tariffs and war drums will only speed up this process. Both political parties are complicit in the hallowing out of America. They deny their failures or any future risks; let alone, how to address them.

[JJackson]

I would recommend reading Richard Feyman's "What do you care what other people think?" section on his experiences on the Roger's Commission report not so much for the O-ring investigation but on the absurdity of NASA's bizarre risk assessment methodology. It is also an interesting insight into the workings of such commissions - with the other members happily taking the NASA guided tour while he found the techies and grilled them on how risk assessments were calculated. He refused to sign the final report unless he was allowed to add a critical appendix.
The gist of which can be found in the Wikipedia's
https://en.wikipedia.org/wiki/Rogers_Commission_Report
It is a long time since I read it so my apologies if I have mis-remebered anything.

[Fred]

VV,

"What killed 346 people was deregulation and the politicians who cut FAA funding and allowed Boeing to self-certify the safety of their aircraft. "

So engineering design was not a cause? Which specific cut to FAA funding caused this then? Why?

"To get EU and China’s recertification the Max’s fix will have to be comprehensive and make the plane safe to fly."

So EU and China certifiations previously existing had no inherent value as they simply went along with the US FAA?

[Lars]

Unfortunately, your analysis sounds well reasoned. Until we get America 3.0, nothing will change and the deterioration continues.

[Fred]

Bablefish,

As I understand it the design issues revolve around engine size and placement used to avoid redesign, retooling and testing associated with an entire new airframe. To compensate a software system controlled flap position during takeoff/landing and was active during all operations. Added to this was utilization of a single " single pitch sensor or AOA (angle of attack) sensor. The jet has two,..." Thus a single point of failure causes a catastrophic failure of the flap positioning. In addition training for certification was set at as little as one hour?

A few basic questions come to mind. What was the cost of this generation of Max-8s? What was the actual installed cost of the second AOA sensor (not the price they wanted to charge.) That marginal cost just sunk a few billion off the company revenue stream. Who in executive leadership thought that opotion, only one AOA sensor, was a reasonable design to take to market? In addition who in the pilots union was willing to accept a single hour of training time as valid in transfering to a new airframe?

[BabelFish]

Fred, it reminds me so much of Challenger. Who in the Astronaut Office was OK with the O-Ring reports? Just collective numbness to the possbility that this was introducing a huge risk factor.

More than that, what about the mechanisms to alert Boeing and the airlines that something was seriously amiss? Even before the Lion Air crash pilots were reporting unacceptable incidents with MCAS. As I said, corporate cultures are lethal to anyone who is perceived as messing with the gravy train.

[walrus]

Thank you so much for your clear description of the Boeing problem. I worked in airline engineering for six years and visited Seattle, Renton and Everett a lot. I watched the 767 prototype being built - large lumps of black painted pine bolted to the airframe representing stuff yet to be delivered.

Vietnam Vets comments regarding the mcdonnell douglas merge are to the point. The Boeing I dealt with was run by engineers with humility. Whenever I dealt with McDonnell Douglas it was always “what would you know? you’re just a user. We designed the DC3’. They $5@#ed Boeing management.

Fred, this is not a simple engineering failure with a single cause. It is not linear. The failure involves aspects of marketing, pilot training, design, manufacture, operational practice, procedures, documentation regulations and oversight and of course money. There is never one single cause. This truism is encapsulated in Prof. James Reasons “swiss cheese model” of accident causation.

https://en.wikipedia.org/wiki/Swiss_cheese_model

[VietnamVet]

Fred,

The Seattle Times has had a good series of articles on the 737 Max. Funds to oversee flight safety were cut by both political parties. The FAA plant representatives who oversee aircraft safety are now paid by Boeing not public servants. My impression is that the political appointees who rotate through government and corporate jobs believe that the greater their income the better it is for them and everyone else. The FAA assumed that Boeing wouldn’t design a flight critical system dependent on one sensor that if it went bad would dive the airplane into the ground. But, Boeing did. Boeing did not ground the fleet after the Lion Air crash when the horizontal stabilizer jackscrew was found in the full nose down position making flying impossible. This was all due to pressure to keep pilot training costs down. Another example of the toxic work environment at Boeing since the merger was reporting that the staff didn’t dare tell the Boeing CEO when they rolled out the 787 it wouldn’t be another year before they could fly it.

Before I retired I sat in on telephone conversations with Canadian and Australian regulators. I assume the foreign aviation authorities had similar sharing agreements with the FAA. After this how can Canada, EU or China trust American aviation oversight? Boeing and Congress shot the American aircraft industry in the foot just to make a little more money for themselves.

[SAC Brat]

I suspect the MCAS was presented as an evolution of the earlier SMYD system on the 737NG, which also uses a single AOA sensor input. The SMYD system had less authority to drive the horizontal stabilizer trim system than the MCAS eventually needed.

[SAC Brat]

A characteristic I do not care for with the 737 was that with the 737NG series Boeing, probably due to their larger customers' requests, did not upgrade the avionics package from the earlier architecture. They stayed with two air data systems and no central maintenance system.

Airbus with the A320 family in the 1980s used three air data systems and a maintenance computer. This architecture, seen in all Airbus aircraft since and Boeing 747-400s, 777s and 787s allows the addition of another layer of safety by allowing trend monitoring of aircraft system health from telemetry. The industry is at a point where data storage is large and cost effective, and now analysis tools are being developed to alert exceedances. This allows alerting of trends before the flight crews see in-service problems.

https://www.yourprops.com/movieprops/default/yp_50c78a57701b67.58244478/2001-A-Space-Odyssey-A-E-35-Unit-Failure-Prediction-Hardcopy-1.jpg

[optimax]

It would be important to know when problems with the Max design were first noticed. By whom? Who in management decided it was more important to get an airplane with dangerous design flaws to market than lose the money in a redesign? Congress should be paying more attention to that, but they like the smokescreen and drama of impeachment.

[b]

Good post.

One quibble

Focus on the fact that the safest version of MCAS, using both sensors rather than one, cost more money. And so many airlines did not order it.

That never was an option. The airlines did not even know that MCAS existed.
The option was a warning light "AoA sensors disagree with each ther" that some airlines (American) ordered only to learn a year later that it did not work at all.

MCAS was based on one sensor because basing it on two sensors would have caught FAA attention as it would mean that MCAS is a flight critical issues (which it obviously is).

There s still one big issue with the MAX and its predecessor the 737 NG. As Mansour Pilot shows the manual trim does not work under critical circumstance. I and others have written about that but the mainstream media has yet to pic up on it.

https://www.moonofalabama.org/2019/05/boeing-737-max-crash-reveals-a-severe-problem-with-older-boeing-737-ngs.html

[Fred]

VV,
Thanks for that link, very helpful.

"https://www.seattletimes.com/business/boeing-aerospace/failed-certification-faa-missed-safety-issues-in-the-737-max-system-implicated-in-the-lion-air-crash/

"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 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.

The behavior of a plane in a high angle-of-attack stall is difficult to model in advance purely by analysis and so, as test pilots work through stall-recovery routines during flight tests on a new airplane, it’s not uncommon to tweak the control software to refine the jet’s performance."

Those details are important to understanding how the design came into being, right along with the regulatory approval. Would anybody in the FAA know that " behavior of a plane in a high angle-of-attack stall is difficult to model in advance purely by analysis" and that the intial settings might change? Neither the author of the story nor the anonymous sources appear to have asked that very salient question.

"The people who spoke to The Seattle Times and shared details of the safety analysis all spoke on condition of anonymity to protect their jobs at the FAA and other aviation organizations." Reminds me of the completely un-related stories surrounding the Mueller probe, where much of what is leaked to the press is anonymous.

"After this how can Canada, EU or China trust American aviation oversight?"

I think you have that wrong. How can Canada, the EU or China trust their own governments who simply rubber stamped somebody else's work? A bunch of government employees in Canada, the EU and China should probably be fired, starting witht he ministers of their aviation authorities for not doing their jobs.

[BabelFish]

From an article in Aviation Weekly on MCAS training for reinstatement to flying status. The whole is worthy of a read, IMO.

"A more reliable MCAS system and better training are two of the requirements that FAA has put on removing its MAX operations ban. Other regulators are taking FAA’s work into account, but also are conducting their own evaluations of Boeing’s changes, which still have not been finalized. The result: the 370-aircraft in-service MAX fleet will almost surely be cleared to fly in phases, with U.S. operators likely to fly first. The exact timeline remains unclear."

"American Airlines management has signaled that it is willing to adopt whatever APA believes is needed to ensure its 4,000 737 pilots are comfortable operating the MAX, Tajer said. That means APA’s FSB comments will likely become American’s training standard."

And this unfortunate bon mot: "APA’s push, Tajer said, is about ensuring that MAX training standards are set as high as possible, as not every airline will go beyond the minimum requirements."

The question of why wasn't this done at the outset of the MAX service will hang over this like the hubris that still hovers of the story of the Titanic.

https://aviationweek.com/commercial-aviation/american-airlines-pilots-boeing-max-crews-need-better-mcas-training

[Stanley]

And this is what happens in profit-motivated corporate environments where CYA is king and "leaders" can't make decisions. A friend of mine recently retired from Bo and told me that he worked in the risk analysis group. It was frustrating because nobody in the corp ever wanted to hear from his group! Oh well.

But only a few hundred unlucky souls were lost.

Now take a look at this link: https://en.wikipedia.org/wiki/Candida_auris
This is a form of killer yeast that was first discovered in 2009 and is now rapidly taking over hospitals all over the world, as well as the U.S.A. and it kills "30-60 percent of people who get it. Thus we can safely figure this is a potential population reduction mechanism unless something is done to counter it, and FAST! Yet, do we hear anything about this? No we don't. Is anyone aware, and suitable alarmed? Well, if so, they are operating at the WHO or CDC levels, corporate-like but without profit motive so essentially even less efficient et al. Think about this next time your read something like that story about an Alziemers drug that wasn't followed up.

[BabelFish]

Note: The Aviation Week link is not behind a paywall but does require registration to access "free content."

[doug]

The Boeing event greatly concerns me, a coder, EE, and pilot, for I can almost see how the failure, which was in the basic design, occurred.

It's in part culture, which, in large safety critical organizations, can evolve into necessary checkboxes and processes. They work but are also slow. Then, when an urgent market response occurs, pressure ramps up.

My first job, a summer one at Analog Devices, was in QC evaluating and testing to specs new designs out of engineering to detect problems before a product was put into production. This involved lots of testing and process following to find possible issues and get them back to engineering.

I rather quickly determined the most effective approach, which wasn't my assigned job, was to analyze the design first, find the most likely points of failure, and test that first but, of course, completing a test suite was still required. Finding a failure point early sped things up. While engineering didn't particularly like the rapid detection of problems, they quickly came to appreciate it because it allowed an overall increase in the speed of product development and I got a fat raise halfway through the summer.

Organizations, particularly in areas of critical safety, need to encourage workers at all levels to find (but not just imagine) potential problems and reward them. Even when it may be perceived as throwing a monkey wrench into a time critical plan. But it actually speeds things along. But it has to be in the culture.

[Mark Logan]

The contributing factor was a desire by the airlines to not have to re-certify their pilots for the MAX, saving them millions. A selling point which tragically trumped engineering concerns during the decision process. Chalk it up a Bureaucrats 1, Artists O.

A fatal flaw, combined with operator ignorance and an assumption nobody would ever do something that stupid on a thing so critical.

Reminds of Chernobyl, "Why worry about something that can't happen."

[b]

The question of why wasn't this done at the outset of the MAX service will hang over this like the hubris that still hovers of the story of the Titanic.

Boeing will have to pay a penalty of $1 million for each 737 MAX plane South-West purchases if the 737 MAX requires extra simulator training.