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Boeing Will Have To Stop Its 737 MAX Production Line. What will Trump Do To Avoid It?
The grounding of the Boeing 737 MAX will be further extended. Major airlines have already moved the date for the return of the MAX into passenger service to April 2020. They will have to move it again.
After the first 737 MAX crashed in October 2018 the Federal Aviation Administration calculated that it was likely that about 15 more fatal crashes would happen during the 45-year life of the 737 MAX fleet worldwide. Despite knowing that another crash was likely the FAA did not order the planes to be grounded. Only after a second MAX came down in March of this year did the FAA react properly. It was the last regulator to do so.
Global trust to the FAA and Boeing was lost and other international safety regulators are now taking their own detailed look at the planes problems. That process is far from over.
Since the 737 MAX plane type was grounded Boeing has announced again and again that the re-certification of the planes and their return-to-service was just two months away. The always unrealistic announced return date helped to hold up Boeing's stock price and put the FAA under pressure to agree to Boeing's changes. The new FAA administrator Stephen Dickson has finally had enough of it and personally told Boeing's CEO Dennis Muilenburg to shut up:
“The Administrator is concerned that Boeing continues to pursue a return-to-service schedule that is not realistic due to delays that have accumulated for a variety of reasons,” the email states. “More concerning, the Administrator wants to directly address the perception that some of Boeing’s public statements have been designed to force FAA into taking quicker action.”
“The Administrator wants to make clear that both FAA and Boeing must take the time to get this process right. Safety is our top priority and the Administrator believes public statements must reflect this priority,” the email states. “The purpose of the meeting is to ensure Boeing is clear on FAA’s expectations.”
There are still several open issues which Boeing has to fix before the plane can go back into service.
The old Maneuvering Characteristics Augmentation System (MCAS) system which caused the crashes used only one Angle of Attack sensor. The logic of its activation was running on only one of the two Flight Control Computers (FCC). Boeing had classified an MCAS failure as a 'MAJOR' incident. MCAS would therefore not require redundancy. But the two accidents have proven that an MCAS failure is a 'CATASTROPHIC' event and that the system requires a much higher degree of safety and redundancy.
The new MCAS version will use at least two AoA sensors and additional logic to compare their values. It will run on both Flight Control Computers which will compare their results and only act if those are equal. Previously a Boeing 737 could in principal fly without a functioning Flight Control Computer. It was not safety critical to have both of them. But now both are required for safety reasons. That again requires that the software running on them can not be allowed to crash the computer. It must be error free.
In November the European Union Aviation Safety Agency (EASA) demanded that Boeing provide documentation of a full formal audit of the software. Boeing played down the issue and the media quoted a person who said who said it would take 'weeks' to do that. As I have done audits of industrial software systems I had a good laugh at that. Even a large team will need several months to do a full formal audit of an FCC.
Another major new issue came up only recently after regular line pilots got confused during simulated MCAS incidents:
Pilots managed to cope with the various emergency flight scenarios they were confronted with, including, for example, a bird strike wiping out an angle of attack sensor at an altitude of 4,000 feet. However, regulators observing the tests were concerned that some of the pilots didn’t follow the expected procedures.
“They were using the wrong checklists,” said one person with knowledge of the tests, adding that the European Union Aviation Safety Agency (EASA) in particular may now require changes to the procedures and checklists.
A failure of one of the AoA sensor that drive MCAS leads to number of cockpit alarms. There will be speed warnings, stick shaker stall warnings, altitude warnings and some sirens that might go off. Each alarm requires the pilot to respond in certain ways. But with multiple alarms going off it is difficult for a pilot to analyze the root cause of the problem. During the simulator sessions more than half of the airline pilots reacted with the wrong procedure. It seems evident that the pilots need extensive additional training to fly a revamped 737 MAX. To save costs the airlines and Boeing had tried to avoid that.
There may still be additional issues with the MAX that must be fixed. While the FAA and EASA have taken the lead in the re-certification process of MAX, the biggest customer country for the plane is China. Yesterday the Civil Aviation Administration of China (CAAC) let it be publicly know that it has additional questions:
China has raised “important concerns” with Boeing Co (BA.N) regarding design changes proposed to end the grounding of the Boeing 737 MAX airliner, Beijing’s aviation regulator said on Thursday, declining to say when it might fly in China again.
The remarks broke months of public silence from China, the first country to ground the 737 MAX in March following the second deadly crash involving the model in less than five months.
Neither the FAA, nor EASA, nor the CAAC are happy with the several layers of band aid Boeing put onto the 737 MAX. Boeing should take some radical steps to change the root cause that required an MCAS system in the first place. It could change the aerodynamics of the plane to defeat the nose up attitude of the aircraft. That would cost additional money and possibly more time. But it is probably the only solution that everyone can accept.
With no end in sight to the grounding of the MAX Boeing will soon have to stop producing more of the planes:
The issue is finding parking for and managing the inventory of more than 400 airplanes that will have been produced by the end of December. January will add another 42 MAXes at the current production rate, and so on.
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All this means Boeing executives have to decide very soon—perhaps as early as this month, more likely in January—whether to reduce production or suspend it entirely.
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Boeing’s 2019 financial results will be announced Jan. 29. A suspension of stock dividends is already expected, a major move by Boeing that the Board has resisted since the grounding. (Stock buybacks were suspended right away.)
If a decision is made to cut or suspend production, an announcement may come before the earnings call on the 29th.
There are thousands of companies, big and small, involved in building an airplane. If Boeing has to shut down the production line many of the hundred thousand people involved will have to move on to do something else. The people and their know-how will try to find someone else to work for. Some of the companies involved may go bankrupt. That will make the later restart of the production line difficult and costly.
But Boeing's current stock of 400 planes will already take more than a year to clear. Boeing simply can not afford to make hundreds of new planes that are not allowed to fly.
Boeing's lobbyists emphasize that Boeing is one of the largest U.S. exporters and that several hundred thousand people are involved in building its planes. If Boeing has to shut down its 737 production line many of them will lose their jobs.
That will not look good for the sitting president during a re-election year. But what could Donald Trump do to avoid it?
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Previous Moon of Alabama posts on Boeing 737 MAX issues:
Back in March, with the second accident still very fresh, I made a statement that was proven wrong:
Too Big To Fail Banks, imposed misery and death on tax payers globally, but they benefited from an apparently vague link between the cause and its effect. TBTF Boeing does not share that benefit, their failure directly translates in death/injury, before everyone’s scrutiny. It will be interesting to follow the developments of this story. The comparatively low quality of the manipulation and mystification to be achieved. Gladly there are signs it will be inadmissible any kind at various levels of influence in the global scale.
As it happens, Boeing PR was very effective misdirecting its responsibility on the accidents, first there were the pilots, then the bad training, then the third world operator, then the bad maintenance… But after the second accident it became impossible to hide MCAS, the flawed system that is today not in dispute as the main culprit of the accidents, it was their design that had to be disallowed from public view. If MCAS became public all hell would brake loose, Boeing PR new exactly what to do if they reached that point: framing any discussion on a subjective basis, although one which would be painted all over with aerodynamic concepts and for that reason scientifically dense.
How to keep it subjective while scientific at the same time? By denying access to quantitative data which so far Boeing have been the only producers of, assuring the discussion to be kept on a qualitative basis at best. The resulting tension morphed into a simple question: Is the MAX a (longitudinaly) stable airplane?
What does that quantitative data consist of? Regulation imposed requirement of Boeing’s MAX flight tests, those with and those without MCAS, the latter the condition that imposed the introduction of this augmentation system. It is the purpose of augmentation systems to correct for aerodynamic insufficiencies. As any honest participant of this discussion, mostly inclined on either response, will tell you: We don’t know and we currently can’t know the answer for that question.
But if we can’t know either way, what should be our position. As it happens we are required into a very specific fallback position. Rationale for which I share, as posted in another forum – Leeham News. Slightly edited, the post is divided into three parts, including a FORMAL and a TECHNICAL part, the following is my best attempt at objectifying the current state of affairs:
Sources mentioned CFR part 25, Lion Air Accident Report, JATR report.
Well, this seams appropriate. Friends, and all those who appreciate logic…
A) We can find four stances regarding the MAX’s stability:
a) “thinking that MAX is” unstable
b) having moderate/strong suspicions that MAX is unstable
c) having moderate/strong suspicions that MAX is stable
d) having “settled” that it is stable
Note that only A.a) and A.d) express certainty, but are also mutually exclusive as are A.b) and A.c). Speaking for myself and as I began to approach this from a more informed point of view, I fit in position strong b). There may be those that are neutral but we can skip that stance.
B) Before going further in this logic exercise, lets keep the simple intuition that stability is the ability for an aircraft to return to its trimmed regime (AoA and airspeed) after being affected by any disturbance (it balances itself out). But lets suspend the technical discussion regarding the concept and agree that static stability is defined authoritatively in CFR part 25:
STABILITY
§25.171 General.
The airplane must be longitudinally, directionally, and laterally stable in accordance with the provisions of §§25.173 through 25.177. In addition, suitable stability and control feel (static stability) is required in any condition normally encountered in service, if flight tests show it is necessary for safe operation.
(…)
GENERAL
§25.21 Proof of compliance.
(…)
(e) If compliance with the flight characteristics requirements is dependent upon a stability augmentation system or upon any other automatic or power-operated system, compliance must be shown with §§25.671 and 25.672.
C) It simply follows that for one to assert objectively about the stability of an aircraft, one needs only to observe dispositions in §§25.173 through 25.177 and to know the results of the tests from the section §25.175 Demonstration of static longitudinal stability, and in addition prove compliance with §§25.671 and 25.672.
D) Lets also agree that those tests are a requirement, having failed the tests an aircraft can’t be said to comply with defined static stability. One cannot state any aircraft or rock is longitudinally stable until those tests are made and turn positive. IMPORTANT – it establishes the onus being on the claim of stability, not on otherwise. ie. by convention an aircraft is as stable as a ballistic rock until proven otherwise!
E) FORMAL facts granted:
1) Only flight tests provide certainty either way.
2) Only Boeing had access to the results of the full batch of certifying tests (with and without MCAS).
3) FAA/EASA/Regulators only had access to partial results of tests (with MCAS only).
4) Only FAA/EASA/Regulators can technically validate the tests and formally emit the certification, in this order.
5) Technical Experts/Flight enthusiasts/Public had no access to any test results at all.
I invite anyone to dispute any of the above.
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Conclusion 1: Only Boeing can claim technically that MAX without MCAS is longitudinally stable because of E.2). No one else can.
Conclusion 2: The Regulators can’t claim neither technically, neither formally that MAX without MCAS is longitudinally stable because of E.3). Not even Boeing because of E.4).
Conclusion 3: Everyone else in E.5) is required to consider MAX as stable as a ballistic rock, because of Conclusion 2. This includes members of any opinion group A.a), A.b), A.c) and A.d): Technically because of E.2) – only Boeing has seen the full batch of tests. And Formally because of D) – demonstration onus on stability claim lies on Boeing.
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(…)
Do notice we don’t even need to bring MCAS and its complexity to the table to claim with certainty that Boeing 737 MAX IS NOT Longitudinally Stable, in fact that position is required formally by one submitting to CFR Part 25. If this was not materially true, MAX would be enjoying its certification and happily flying.
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If we do touch MCAS, attempting a view on the technical side…
F) TECHNICAL qualitative/quantitative facts in public domain:
1) Stability must be considered both at an Aerodynamic and Pilot Control level, it is highly influenced by Pitch/AoA and Airspeed – suitable stability and control feel (static stability) (from CFR 25 – §25.171)
1.a) The speed must return to within 10 to 7.5 per cent of trim speed after stick “disturbs” pitch and is slowly relaxed depending on flight regime test conducted. (§25.173)
1.b) A set ratio between stick force versus speed exists amounting to 1 pound for each 6 knots. (§25.173)
(from §§25.671 and 25.672)
2) Stability Augmentation systems:
2.a) Affect Pilot handling Control FEEL (pounds / knots per second) (ie. EFS – Elevator Feel Shift – Elevator)
2.b) Affect Aircraft direct Control SURFACES (deceleration knots per second) (ie. STS – Speed Trim System – Stabiliser)
2.c) Are ultimately invoked at any speed under several flight regimes in corners of the flight envelope before a STALL becomes imminent (identification/prevention systems)
2.d) Must show “by analysis, tests, or both”
2.e) Must consider Gusts and Turbulence Loads
2.f) Upon failure/malfunction of flight control system and surfaces (including trim, lift, drag, and feel systems) allow safe control at any speed and altitude at least within a practical operational flight envelope
2.g) “The trim, stability, and stall characteristics are not impaired below a level needed to permit continued safe flight and landing” (cited in full)
2.h) Provide warning, permit counteraction
3) Manoeuvering Characteristics Augmentation System (MCAS) as an Augmentation system:
3.a) Constitutes a novelty, certified for the first time with MAX (only used elsewhere in one also recent military craft)
3.b) Only weaker authority version was certified compared with the final delivered (0.6deg instead of final full 2.5deg)
3.c) Acts directly on the Stabiliser with higher rate of movement at 0.27deg/sec (compared with STS or Manual Electric Trim at 0.2/sec)
3.d) Is introduced in addition to, not in place of existing system STS (with which it is hardly integrated with, moderated or bounded by)
3.e) FCOM Pilot flight manual contains no mentioned or explanation system function (aside of its acronym)
3.f) Acts when autopilot is OFF, flaps up, depending on STALL limit AoA angles (lacking AoA indicator installed by default)
3.g) Acts on both AoA and Mach data (AoA being retrieved from a single sensor (schedule of which is unknown to pilots)
3.h) Removed two of the fail-safes available to the pilot associated with similar STS (Column Switch CUTOFF, STAB CUTOUT Manual/Auto separation)
I invite anyone to dispute any of the above, keeping in mind that 1) and 2) are mostly paraphrases of CFR Part 25, and 3) are commonly undisputed facts mostly revealed within official reports, Lion Air Accident and JATR.
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Observation 1: Attempts at characterizing MCAS as a mere control FEEL system unrelated with eventual/imminent STALL for the effect of diminishing its importance on Static Longitudinal Stability are immediately defeated by 1), 2.a) 2.f). FEEL systems are augmentation systems intimately related with Pitch/AoA and Airspeed and subsequently with STALL antecipation/prevention. Sorry Boeing PR.
Observation 2: MCAS is provided with the highest order authority inherent to the Stabiliser versus Elevator Control Surfaces, invalidating the notion that this choice is made to maintain Pilot’s attributed Elevator authority (to somehow preserve Boeing control philosophy). Elevator which could only be disauthorized by the Stabiliser when working in inverted directions, see 1.b) – Weak Pilot Elevator ANU effect with high forces vs Stronger Stab MCAS AND effect with added speed. Sorry Rob.
Conclusion 4: B737 MAX-8’s MCAS is essential for its static stability. This is undisputable, at least formally, but also technically, given the relative importance of its control authority versus equivalent systems on the model it replaces (B737-800), which should at least be indicative of the magnitude of the issue it is addressing, again: static longitudinal stability. If not, notice the incremental authority with respect to points 1.b), 2.h), 3.b), 3.c), 3.d), 3.e), 3.f), 3.g) and finaly 3.h).
Question 1: If one is not disputing the aplication of CFR part 25, given these Observations and Conclusions, how can anyone aside of Boeing officials, be confident that B737 MAX-8 without MCAS will not lead to other fatal accidents, eventuality now explained not by the malfunction of the cure (MCAS) but by the treated disease (insufficient static stability)?
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Notice also that I haven’t yet touched the ugly stuff:
– Blaming Pilot training, a proper one which Boeing itself denied access
– Nov 2018 AD, calling for runaway trim stabiliser NNC, when Boeing must have known it would hardly provide assurances to prevent a repeat of the tragedy
– Certification process with numerous flaws, concidently overlaping areas with respect to critical information revealing the impact of MCAS
– Misrepresentation in Boeing’s engineering simulator of MCAS effect of Control Feel forces
Question 2: How can anyone trust a single word out of Boeing’s PR?
Requirement 1: The Regulator must act on behalf of the flying public as is its institutional mandate in order to assert the compliance of Boeing’s 737 MAX series as a safe aircraft models.
Posted by: Vasco da Gama | Dec 14 2019 17:52 utc | 36
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