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737 Max - A bigger problem than a software update, from Peter Myers

(1) Boeing must stop producing the 737 Max

(2) 737 Max - A bigger problem than a software update

(3) 737 Max: long-standing design issue over Trim; Training Manual for 737-200 spell out


(1) Boeing must stop producing the 737 Max

by Peter Myers, April 6, 2019

Boeing has lowered its monthly production of 737 Maxs. But it should stop producing them altogether. The evidence is in the two articles below.

Airlines won't be able to fly these planes because CUSTOMERS are afraid and will refuse to fly in them. The result is that airlines will refuse to fill their contracts.

If Boeing keeps making them, they'll have to store them, because no airline will accept them.

This issue will also worsen the US Trade Deficit.

The best thing Boeing can do is redesign the Max as a new plane, i.e. not a 737. Calling it a 737 was a fudge, anyway.

It will take years, and the company will lose sales, whatever happens. But this course would save the company's reputation and fortunes in the long run.

Boeing executives should be prosecuted for rushing an unsafe plane into production; the Board should be sacked.

(2) 737 Max - A bigger problem than a software update

Boeing’s effort to get the 737 Max approved to fly again, explained

A bigger problem than a software update.

By Matthew  Apr 5, 2019, 10:30am EDT

On Thursday, Boeing for the first time officially took responsibility for the two crashes of 737 Max jets that got the planes grounded by regulators.

Claiming responsibility was part of an attempt to get the planes approved to fly again. Boeing was trying to say that it now understands why the planes crashes — flawed software — and has a plan in place to replace it with new software that will eliminate the problem and persuade regulators to get the planes off the ground. But then Friday morning, the company announced that it had found a second, unrelated software flaw that it also needs to fix and will somewhat delay the process of getting the planes cleared to fly again.

All of which, of course, raises the question of why such flawed systems were allowed to fly in the first place.

And that story begins nine years ago when Boeing was faced with a major threat to its bottom line, spurring the airline to rush a series of kludges through the certification process — with an underresourced Federal Aviation Administration (FAA) seemingly all too eager to help an American company threatened by a foreign competitor, rather than to ask tough questions about the project.

The specifics of what happened in the regulatory system are still emerging (and despite executives’ assurances, we don’t even really know what happened on the flights yet). But the big picture is coming into view: A major employer faced a major financial threat, and short-term politics and greed won out over the integrity of the regulatory system. It’s a scandal.

The 737 versus 320 rivalry, explained

There are lots of different passenger airplanes on the market, but just two very similar narrow-body planes dominate domestic (or intra-European) travel. One is the European company Airbus’s 320 family, with models called A318, A319, A320, or A321 depending on how long the plane is. These four variants, by design, have identical flight decks, so pilots can be trained to fly them interchangeably.

The 320 family competes with a group of planes that Boeing calls the 737 — there’s a 737-600, a 737-700, a 737-800, and a 737-900 — with higher numbers indicating larger planes. Some of them are also extended-range models that have an ER appended to the name, and, as you would probably guess, they have longer ranges.

Importantly, even though there are many different flavors of 737, they are all in some sense the same plane, just as all the 320 family planes are the same plane. Southwest Airlines, for example, simplifies its overall operations by exclusively flying different 737 variants.

Both the 737 and the 320 come in lots of different flavors, so airlines have plenty of options in terms of what kind of aircraft should fly exactly which route. But because there are only two players in this market, and because their offerings are so fundamentally similar, the competition for this slice of the plane market is both intense and weirdly limited. If one company were to gain a clear technical advantage over the other, it would be a minor catastrophe for the losing company.

And that’s what Boeing thought it was facing.

The A320neo was trouble for Boeing

Jet fuel is a major cost for airlines. With labor costs largely driven by collective bargaining agreements and regulations that require minimum ratios of flight attendants per passenger, fuel is the cost center airlines have the most capacity to do something about. Consequently, improving fuel efficiency has emerged as one of the major bases of competition between airline manufacturers.

If you roll back to 2010, it began to look like Boeing had a real problem in this regard.

Airbus was coming out with an updated version of the A320 family that it called the A320neo, with “neo” meaning “new engine option.” The new engines were going to be more fuel-efficient, with a larger diameter than previous A320 engines, that could nonetheless be mounted on what was basically the same airframe. This was a nontrivial engineering undertaking both in designing the new engines and in figuring out how to make them work with the old airframe, but even though it cost a bunch of money, it basically worked. And it raised the question of whether Boeing would respond.

Initial word was that it wouldn’t. As CBS Moneywatch’s Brett Snyder wrote in December 2010, the basic problem was that you couldn’t slap the new generation of more efficient, larger-diameter engines onto the 737:

One of the issues for Boeing is that it takes more work to put new engines on the 737 than on the A320. The 737 is lower to the ground than the A320, and the new engines have a larger diameter. So while both manufacturers would have to do work, the Boeing guys would have more work to do to jack the airplane up. That will cost more while reducing commonality with the current fleet. As we know from last week, reduced commonality means higher costs for the airlines as well.

Under the circumstances, Boeing’s best option was to just take the hit for a few years and accept that it was going to have to start selling 737s at a discount price while it designed a whole new airplane. That would, of course, be time-consuming and expensive, and during the interim, it would probably lose a bunch of narrow-body sales to Airbus.

The original version of the 737 first flew in 1967, and a decades-old decision about how much height to leave between the wing and the runway left them boxed out of 21st-century engine technology — and there was simply nothing to be done about it.

Unless there was.

Boeing decided to put on the too-big engines anyway

As late as February 2011, Boeing chair and CEO James McNerney was sticking to the plan to design a totally new aircraft.

“We’re not done evaluating this whole situation yet,” he said on an analyst call, “but our current bias is to move to a newer airplane, an all-new airplane, at the end of the decade, beginning of the next decade. It’s our judgment that our customers will wait for us.”

But in August 2011, Boeing announced that it had lined up orders for 496 re-engined Boeing 737 aircraft from five airlines.

It’s not entirely clear what happened, but, reading between the lines, it seems that in talking to its customers Boeing reached the conclusion that airlines would not wait for them. Some critical mass of carriers (American Airlines seems to have been particularly influential) was credible enough in its threat to switch to Airbus equipment that Boeing decided it needed to offer 737 buyers a Boeing solution sooner rather than later.

Committing to putting a new engine that didn’t fit on the plane was the corporate version of the Fyre Festival’s “let’s just do it and be legends, man” moment, and it unsurprisingly wound up leading to a slew of engineering and regulatory problems.

New engines on an old plane

As the industry trade publication Leeham News and Analysis explained earlier in March, Boeing engineers had been working on the concept that became the 737 Max even back when the company’s plan was still not to build it.

In a March 2011 interview with Aircraft Technology, Mike Bair, then the head of 737 product development, said that reengineering was possible.

“There’s been fairly extensive engineering work on it,” he said. “We figured out a way to get a big enough engine under the wing.”

The problem is that an airplane is a big, complicated network of interconnected parts. To get the engine under the 737 wing, engineers had to mount the engine nacelle higher and more forward on the plane. But moving the engine nacelle (and a related change to the nose of the plane) changed the aerodynamics of the plane, such that the plane did not handle properly at a high angle of attack. That, in turn, led to the creation of the Maneuvering Characteristics Augmentation System (MCAS). It fixed the angle-of-attack problem in most situations, but it created new problems in other situations when it made it difficult for pilots to directly control the plane without being overridden by the MCAS.

On Wednesday, Boeing rolled out a software patch that it says corrects the problem, and it hopes to persuade the FAA to agree.

But note that the underlying problem isn’t really software; it’s with the effort to use software to get around a whole host of other problems.

Trevor Sumner @trevorsumner

 1of x: BEST analysis of what really is happening on the #Boeing737Max issue from my brother in law @davekammeyer, who’s a pilot, software engineer & deep thinker. Bottom line don’t blame software that’s the band aid for many other engineering and economic forces in effect.??????

1:04 AM - Mar 17, 2019 · Brooklyn, NY

Recall, after all, that the whole point of the 737 Max project was to be able to say that the new plane was the same as the old plane. From an engineering perspective, the preferred solution was to actually build a new plane. But for business reasons, Boeing didn’t want a “new plane” that would require a lengthy certification process and extensive (and expensive) new pilot training for its customers. The demand was for a plane that was simultaneously new and not new.

But because the new engines wouldn’t fit under the old wings, the new plane wound up having different aerodynamic properties than the old plane. And because the aerodynamics were different, the flight control systems were also different. But treating the whole thing as a fundamentally different plane would have undermined the whole point. So the FAA and Boeing agreed to sort of fudge it.

The new planes are pretty different

As far as we can tell, the 737 Max is a perfectly airworthy plane in the sense that error-free piloting allows it to be operated safely.

But pilots of planes that didn’t crash kept noticing the same basic pattern of behavior that is suspected to have been behind the two crashes, according to a Dallas Morning News review of voluntary aircraft incident reports to a NASA database:

The disclosures found by the News reference problems with an autopilot system, and they all occurred during the ascent after takeoff. Many mentioned the plane suddenly nosing down. While records show these flights occurred in October and November, the airlines the pilots were flying for is redacted from the database.

These pilots all safely disabled the MCAS and kept their planes in the air. But one of the pilots reported to the database that it was “unconscionable that a manufacturer, the FAA, and the airlines would have pilots flying an airplane without adequately training, or even providing available resources and sufficient documentation to understand the highly complex systems that differentiate this aircraft from prior models.”

The training piece is important because a key selling feature of the 737 Max was the idea that since it wasn’t really a new plane, pilots didn’t really need to be retrained for the new equipment. As the New York Times reported, “For many new airplane models, pilots train for hours on giant, multimillion-dollar machines, on-the-ground versions of cockpits that mimic the flying experience and teach them new features” while the experienced 737 Max pilots were allowed light refresher courses that you could do on an iPad.

That let Boeing get the planes into customers’ hands quickly and cheaply, but evidently at the cost of increasing the possibility of pilots not really knowing how to handle the planes, with dire consequences for everyone involved.

The FAA put a lot of faith in Boeing

In a blockbuster March 17 report for the Seattle Times, the newspaper’s aerospace reporter Dominic Gates details the extent to which the FAA delegated crucial evaluations of the 737’s safety to Boeing itself. The delegation, Gates explains, is in part a story of a years-long process during which the FAA, “citing lack of funding and resources, has over the years delegated increasing authority to Boeing to take on more of the work of certifying the safety of its own airplanes.”

But there are indications of failures that were specific to the 737 Max timeline. In particular, Gates reports that “as certification proceeded, managers prodded them to speed the process” and that “when time was too short for FAA technical staff to complete a review, sometimes managers either signed off on the documents themselves or delegated their review back to Boeing.”

Most of all, decisions about what could and could not be delegated were being made by managers concerned about the timeline, rather than by the agency’s technical experts.

It’s not entirely clear at this point why the FAA was so determined to get the 737 cleared quickly (there will be more investigations), but if you recall the political circumstances of this period in Barack Obama’s presidency, you can quickly get a general sense of the issue.

Boeing is not just a big company with a significant lobbying presence in Washington; it’s a major manufacturing company with a strong global export presence and a source of many good-paying union jobs. In short, it was exactly the kind of company the powers that be were eager to promote — with the Obama White House, for example, proudly going to bat for the Export-Import Bank as a key way to sustain America’s aerospace industry.

A story about overweening regulators delaying an iconic American company’s product launch and costing good jobs compared to the European competition would have looked very bad. And the fact that the whole purpose of the plane was to be more fuel-efficient only made getting it off the ground a bigger priority. But the incentives really were reasonably aligned, and Boeing has only caused problems for itself by cutting corners.

Boeing is now in a bad situation

One emblem of the whole situation is that as the 737 Max engineering team piled kludge on top of kludge, they came up with a cockpit warning light that would alert the pilots if the plane’s two angle-of-attack sensors disagreed.

But then, as Jon Ostrower reported for the Air Current, Boeing’s team decided to make the warning light an optional add-on, like how car companies will upcharge you for a moon roof.

The light cost $80,000 extra per plane and neither Lion Air nor Ethiopian chose to buy it, perhaps figuring that Boeing would not sell a plane (nor would the FAA allow it to) that was not basically safe to fly. In the wake of the crashes, Boeing has decided to revisit this decision and make the light standard on all aircraft.

Now, to be clear, Boeing has lost about $40 billion in stock market valuation since the crash, so it’s not like cheating out on the warning light turned out to have been a brilliant business decision or anything.

This, fundamentally, is one reason the FAA has become comfortable working so closely with Boeing on safety regulations: The nature of the airline industry is such that there’s no real money to be made selling airplanes that have a poor safety track record. One could even imagine sketching out a utopian libertarian argument to the effect that there’s no real need for a government role in certifying new airplanes at all, precisely because there’s no reason to think it’s profitable to make unsafe ones.

The real world, of course, is quite a bit different from that, and different individuals and institutions face particular pressures that can lead them to take actions that don’t collectively make sense. Looking back, Boeing probably wishes it had just stuck with the “build a new plane” plan and toughed out a few years of rough sales, rather than ending up in the current situation. Right now the company is, in effect, trying to patch things up piecemeal — a software update here, a new warning light there, etc. — in hopes of persuading global regulatory agencies to let its planes fly again.

But even once that’s done, Boeing faces the task of convincing airlines to actually buy its planes. An informative David Ljunggren article for Reuters reminds us that a somewhat comparable situation arose in 1965 when three then-new Boeing 727 jetliners crashed.

There wasn’t really anything unsound about the 727 planes, but many pilots didn’t fully understand how to operate the new flaps — arguably a parallel to the MCAS situation with the 737 Max — which spurred some additional training and changes to the operation manual. Passengers avoided the planes for months, but eventually came back as there were no more crashes, and the 727 went on to fly safely for decades. Boeing hopes to have a similar happy ending to this saga, but so far it seems to be a long way from that point. And the immediate future likely involves more tough questions.

A political scandal on slow burn

The 737 Max was briefly a topic of political controversy in the United States as foreign regulators grounded the planes, but President Donald Trump — after speaking personally to Boeing’s CEO — declined to follow. Many members of Congress (from both parties) called on him to reconsider, which he rather quickly did, pushing the whole topic off Washington’s front burner.

But Trump is generally friendly to Boeing (he even has a former Boeing executive, Patrick Shanahan, serving as acting defense secretary, despite an ongoing ethics inquiry into charges that Shanahan unfairly favors his former employer), and Republicans are generally averse to harsh regulatory crackdowns. The most important decisions in the mix appear to have been made back during the Obama administration, so it’s also difficult for Democrats to go after this issue. Meanwhile, Washington has been embroiled in wrangling over special counsel Robert Mueller’s investigation, and a new health care battlefield opened up as well.

That said, on March 27, FAA officials faced the Senate Commerce Committee’s Subcommittee on Aviation and Space at a hearing called by subcommittee Chair Ted Cruz (R-TX). Regulators committed at the hearing to revamp the way they certify new planes, in light of the flaws that were revealed in the previous certification process.

The questions at stake, however, are now much bigger than one subcommittee. Billions of dollars are on the line for Boeing, the airlines that fly 737s, and the workers who build the planes. And since a central element of this story is the credibility of the FAA’s process — in the eyes of the American people and of foreign regulatory agencies — it almost certainly won’t get sorted out without more involvement from the actual decision-makers in the US government.


(3) 737 Max: long-standing design issue over Trim; Training Manual for 737-200 spell out Trim maneuver

Vestigial design issue clouds 737 Max crash investigations

Jon Ostrower

The Air Current

April 4, 2019

A 53-year old idiosyncrasy in the 737's design is expected to become a focus of the inquests.

The seeds of an intensifying crisis in 2019 with the planet’s most popular commercial airliner may have been planted more than a half-century ago.

Five months after the crash of Lion Air 610, every Boeing 737 Max-trained pilot on the planet was familiar with the MCAS system. They knew how it worked and knew how to disable it should they find it behaving in a way that put their airplane in danger. Flipping two cut-out switches would be sufficient, according to the Boeing guidance as part of the memorized checklist to troubleshoot errant movement of the horizontal stabilizer trim. Then crews would manually hand crank the jet’s trim wheel to right the nose. At least initially, the crew of Ethiopian 302 did just that, according to the preliminary report into the crash released Thursday.

The recovery effort didn’t succeed and the trim wheel didn’t raise the jet’s nose. According to the 33 page report, the crew reactivated the electronic trim controls, causing the MCAS system to activate and push the jet’s nose down for a fourth and final time. With little altitude to recover, the 737 Max impacted the ground near Bishoftu, Ethiopia, killing all 157 aboard. The crash sparked the global grounding of the 737 Max days later.

The non-responsive trim wheel and the crew’s initial by-the-book efforts to save aircraft are expected to be an increasing focus of the myriad of inquiries into the 737 Max and its automated flight control system, according to air safety experts. But a vestigial design idiosyncrasy in the 737 may offer one clear explanation according to a former Boeing flight controls engineer, Peter Lemme, along with the procedures for recovering a badly configured 737 horizontal stabilizer that date to the early 1980s and before.

Three generations of 737s ago, pilots flying the 737-200 — a slightly longer version of the original 1967 airliner — were trained that if the jet’s horizontal stabilizer tilts too far — pushing the jet’s nose downward — hand cranking the trim wheel won’t work (after flipping the cut-out switches) while at the same time pulling back on the controls, according to Lemme and an Australian pilot who sought anonymity to speak freely about his experience training on the 737-200.

The trim wheel barely budges, but why?

As pilots would pull on the jet’s controls to raise the nose of the aircraft, the aerodynamic forces on the tail’s elevator (trying to raise the nose) would create an opposing force that effectively paralyzes the jackscrew mechanism that moves the stabilizer, explained Lemme, ultimately making it extremely difficult to crank the trim wheel by hand. The condition is amplified as speed — and air flow over the stabilizer — increases.

“I’m very confident [this flight control issue is] going to be looked at closely as part of the many reviews that are ongoing with these accidents,” said Jeff Guzzetti, former director of the Federal Aviation Administration’s Accident Investigation Division. Guzzetti also noted that the high rate of speed and steadily maintained engine thrust are also likely to be considered compounding factors.

The FAA announced Wednesday that it formed a joint technical review with NASA, industry representatives and nine civil aviation authorities to examine the 737 Max’s automated flight control systems and training. The joint review is the latest in a series of inquests and follow U.S. Congressional, the Departments of Transportation and Justice and the twin international investigations into the crash of Flight 302 and Lion Air 610 on October 29, 2018 near Jakarta.

Boeing Commercial Airplanes Chief Executive Kevin McAllister said, “We will carefully review the…preliminary report, and will take any and all additional steps necessary to enhance the safety of our aircraft.” The company is currently developing updates to its training and software to “to ensure unintended MCAS activation will not occur again.”

“It’s our responsibility to eliminate this risk. We own it and we know how to do it,” said Boeing Chief Executive Dennis Muilenburg in a lengthy message posted Thursday.

Unresponsive Manual Trim

Three minutes after first experiencing flight controls issues with the Ethiopian 737 Max, the captain of Flight 302, Yared Getachew, asked his first officer “if the trim is functional,” according to the preliminary report. The first officer “replied that the trim was not working and asked if he could try it manually. The Captain told him to try.” Eight seconds later First Officer Ahmed Nur Mohammed “replied that it is not working.” The report notes that the controls of the jet were pulled to raise the jet’s nose from the moment the MCAS system activates erroneously.

What contribution, if any, the lockup — known as a mistrim — played in the Ethiopian crash is unclear, but the revelation of a long-standing design issue adds a fresh layer of complexity into the investigations and what guidance and training was provided to 737 Max pilots to recover from an erroneous activation of the MCAS system.

Lemme posted his initial summation of the conditions that would create a flight control lockup prior to Tuesday evening’s Wall Street Journal report that revealed the crew had initially followed proper procedures. Lemme deliberately included no mention of the Ethiopian crash. Without supporting facts from the preliminary report, Lemme did not want to imply a link to the on-going Ethiopian investigation. The Air Current was interviewing Lemme about the mistrim issue as that news broke on Tuesday evening.

Separately, Lemme has found himself in the middle of the investigation itself and said that he was served on Monday afternoon with a wide-ranging subpoena from the Department of Justice as part of its criminal inquiry into the 737 Max. Lemme left Boeing 22 years ago and was not involved in any aspect of the development of the 737 Max.

Lemme is not the only one to note the compounded challenge of trying to manually crank the trim wheel while attempting to keep the nose of the aircraft raised. YouTube Channel Mentour Pilot, in conjunction with Leeham News, recreated the same conditions inside a 737 Next Generation simulator. The older generation 737 does not have MCAS — a feature exclusive to the 737 Max — but can simulate a horizontal stabilizer’s runaway trim. The video intended to illustrate how the design issue could compound an already difficult situation, even with all the proper procedures carried out. With the trim pushing the nose down and the controls pulled back by the pilot to maintain altitude, the first officer could barely crank the trim wheel, nearly out of breath while fighting the mechanical system. The video was only posted briefly on Wednesday morning before it was removed.

Detailed guidance on handling this situation isn’t part of the contemporary 737 training manual, however it does makes reference to this condition. “Excessive airloads on the stabilizer may require effort by both pilots to correct the mis-trim. In extreme cases it may be necessary to aerodynamically relieve the airloads to allow manual trimming.”

A Roller Coaster Recovery

Training materials from the early 1980s model 737-200 spell out the recovery maneuver directly. “If other methods fail to relieve the elevator load and control column force, use the “roller coaster” technique,” according to Boeing procedures dated February 1, 1982 for flying the 737-200. The original documentation was provided to The Air Current by the Australian pilot from his days flying the early-model 737.

“My company practiced the Boeing-stated ‘roller coaster’ techniques during 737-200 simulator training in those days,” said the pilot in an email.

An excerpt from the 1982 pilot training manual for the Boeing 737-200. Courtesy of Centaurus.

In other words, first relax the controls back to neutral before attempting to crank the trim wheel. Then quickly spin the trim wheel for a few moments, then pull the controls back again. Repeat until the aircraft is stabilized. Think of it like reeling in a fish — it’s incredibly hard to crank the reel handle if you’re pulling back on the rod. You’d relax and lean the rod forward to quickly reel in the next length of line.

In the case of a stabilizer mistrimmed to lower the nose (in an erroneous MCAS activation on the 737 Max), the “roller coaster” is a repeated descending and leveling of the aircraft. The maneuver ultimately relies on having enough altitude to recover and level the aircraft.

The detailed recovery maneuver was not included in the subsequent training documents for the 737 Classics in the mid-1980s, the 737 Next Generation in the 1990s nor most recently with the 737 Max. Additional Boeing documentation dating back to 1975 identified the roller coaster method as the “least desirable” to recover the aircraft during a mistrim situation.

“For some inexplicable reason, Boeing manuals have since deleted what was then — and still is — vital handling information for flight crews,” the Australian pilot wrote on pilot forum PPRUNE.

An earlier version of this article stated that the aerodynamic forces on the tail’s elevator (trying to raise the nose) and horizontal stabilizer (positioned to lower the nose) would combine to paralyze the jackscrew. In fact, the elevator alone would overwhelm the crew’s ability to manually trim the nose upward while struggling to maintain altitude with an improperly configured stabilizer. The graphic and article have been updated to reflect this.

Jon Ostrower is Editor-in-chief of The Air Current. Prior to launching TAC in June 2018, Ostrower served as Aviation Editor for CNN Worldwide, guiding the network's global coverage of the business and operations of flying. Ostrower joined CNN in 2016 following four and half years at the Wall Street Journal. Based first in Chicago and then in Washington, D.C. he covered Boeing, aviation safety and the business of global aerospace. Before that, Ostrower was editor of the award-winning FlightBlogger for Flightglobal and Flight International Magazine covering the development of the Boeing 787 Dreamliner and other new aircraft programs from 2007 to 2012. Ostrower, a Boston native, graduated from The George Washington University's School of Media and Public Affairs with a bachelor's degree in Political Communication. He is based in Seattle.


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