737 Max Updates and Cancellations


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https://www.usatoday.com/story/opinion/2019/10/29/faa-admin-boeing-737-max-will-it-fly-again-column/2487912001/

Seems like it's return isn't guaranteed.

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The FAA is fully committed to address all of the recommendations raised by investigators, including those that pertain to when, whether or how the 737 Max will return to service. As we have said repeatedly, the aircraft will fly only after we determine it is safe.

 

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Who cares how Southwest  feels.  They got what they demanded,  they get what they deserve. 

14,000 Words Of "Blame The Pilots" That Whitewash Boeing Of 737 MAX Failure The New York Times Magazine just published a 14,000 words piece about the Boeing 737 MAX accidents. It is headlined:

On a humourous note, maybe Boeing just wants to be more.....'environmentally friendly'???  

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19 hours ago, dagger said:

The compensation claims from both large Canadian carriers will be something to behold. Westjet wants comp to include what amounts to alienation of affection between passengers and the MAX. A rebuilding trust exercise that will be hard to cost out. 

Notwithstanding potential civil litigation for damages, each settlement will also be a function of leverage. Who has it. Who doesn’t. 

Is WJ going to threaten to switch to Airbus? Is that a credible threat? For AC, it most certainly is including future WB fleet renewal.

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3 hours ago, rudder said:

Notwithstanding potential civil litigation for damages, each settlement will also be a function of leverage. Who has it. Who doesn’t. 

Is WJ going to threaten to switch to Airbus? Is that a credible threat? For AC, it most certainly is including future WB fleet renewal.

I think this might be more than a shot-across-the-bow for both carriers. WJ has a somewhat aging 737-600 and -700 fleet that will need to be replaced in much the same way that Air Canada has a lot of older A319 and A320's. 

I can see one or both Goeing (you see what I did there?) to Airbus for their narrow-body requirements. I can't really see it for the wide-bodies though, AC has a fairly new fleet of 777's and a very new fleet of 787's and WJ has invested a lot into getting their initial 787 ops up and going.

The wildcard for WJ could be the new owners who also have a leasing company with over 500 aircraft already.

I can't think of a case where a company of Boeing's size has ever had this much self inflicted damage. 

 

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3 hours ago, Maverick said:

I think this might be more than a shot-across-the-bow for both carriers. WJ has a somewhat aging 737-600 and -700 fleet that will need to be replaced in much the same way that Air Canada has a lot of older A319 and A320's. 

I can see one or both Goeing (you see what I did there?) to Airbus for their narrow-body requirements. I can't really see it for the wide-bodies though, AC has a fairly new fleet of 777's and a very new fleet of 787's and WJ has invested a lot into getting their initial 787 ops up and going.

The wildcard for WJ could be the new owners who also have a leasing company with over 500 aircraft already.

I can't think of a case where a company of Boeing's size has ever had this much self inflicted damage. 

 

Don’t be so sure that AC does not become an A350 customer.

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13 hours ago, Don Hudson said:

From the archives of the Royal Aeronautical Society, D. P. Davies, (Handling the Big Jets) speaks about design, especially 40:00 to 47:00.

https://www.aerosociety.com/news/audio-the-d-p-davies-interview-on-testing-the-comets-boeing-707-britannia-brabazon/

That was a lot of fun to listen to!

Its not hard to imagine what he would have to say about the certification process of the max. Around the the 1:30 mark the comparisons of the later version of the 707 in reference to stalling characteristics is uncannily similar to what must have took place with the max...only it wasn't properly resolved.

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His comments on the deHavilland Comet are equally interesting, and not flattering to the effort. But "rip-stop" design that Boeing incorporated emerged from the Comet's problems.

The entire KNKT Report is well worth reading, for pilots and management personnel as well as designers, engineers, human-factors / flight safety personnel and even though the matter is far from over for the U. S. Regulator and Boeing, the general public if they wish to know what really happened and why.

For example, take a look at the following sections of the report which detail the Xtra company's work as it relates to the AoA sensor. These sections examine precisely how the left AoA sensor output on the accident aircraft came to be tested as "normal" by Lion Air Mtce but was in fact 20deg out of calibration:

1.6.4 Angle of Attack (AOA) Sensors Historical Record

1.17.3 Xtra Aerospace LLC

2.6 Xtra Aerospace LLC

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Where is this going now?...

The notion that MCAS was intended as "stall prevention" in rare corners of operation is showing up and now being discussed.

The implications are significant. Stall prevention systems are not permitted single-points-of-failure, https://www.satcom.guru/2019/10/flawed-assumptions-pave-path-to-disaster.html

For ease of reference, here is the link to the JATR, https://www.faa.gov/news/media/attachments/Final_JATR_Submittal_to_FAA_Oct_2019.pdf

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I'm not sure who, other than the press, call MCAS a stall prevention device....it's purpose (according to a Boeing test pilot who was at a presentation I attended) was to ensure similar handling characteristics with the 737 NG....to maintain a common type rating.... nothing else.

 

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5 hours ago, anonymous said:

I'm not sure who, other than the press, call MCAS a stall prevention device....it's purpose (according to a Boeing test pilot who was at a presentation I attended) was to ensure similar handling characteristics with the 737 NG....to maintain a common type rating.... nothing else.

 

By pushing the nose down in response to certain power inputs.  Thus lowering the nose to a lower AOA to PREVENT A STALL.

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I think it is semantics.  The system is designed to make the plane behave like an NG by preventing a stall which is defined as a stall prevention system.  Call it anything that makes you feel good but in the most base description, the MCAS is there to prevent a Stall.

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17 minutes ago, boestar said:

I think it is semantics.  The system is designed to make the plane behave like an NG by preventing a stall which is defined as a stall prevention system.  Call it anything that makes you feel good but in the most base description, the MCAS is there to prevent a Stall.

The system introduces nose down trim so that the control feel on the yoke in the pitch axis feels the same as the NG.  To be certified as a common type with the NG the control feel must be similar through all flight regimes. The MAX was too light in pitch feel in the flaps up, high AOA regime to be certified as a common type, hence the need for MCAS.  It essentially puts the airplane in an out of trim state so it feels heavier on the yoke, that’s it.
It has nothing to do with preventing stalls.

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Yep thats the Boeing description.

However the dynamics of it tell a different story.  Left unchecked certain Thrust vectors on the engine installation will cause a pitch up of the airframe, increasing the AOA of the aircraft. (That sounds like the description of an impending stall no?)  Left unchecked the aircraft will eventually stall.

This is something that the NG did not do.  

So to make it behave more like the NG and NOT stall they added MCAS.  Boeing can spin it any way they want to as can others but in the end, no matter what you call it, the end purpose was to prevent the aircraft from reaching a high enough AOA to stall.

 

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Boestar, that’s not my understanding.  It’s spelled out in the regulations for certification as a common type, control feel must be essentially the same.

You are correct in that it is the positioning of the engines that causes the Max to feel light in pitch compared to the NG.  But any aircraft with engines mounted under the wing will pitch up with thrust.

Of course we wouldn’t be discussing this if Boeing hadn’t continued on with this antique, still using cables and pulleys.  FBW and this wouldn’t be an issue.

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It's possible that MCAS was indeed a certification-as-same-type solution before the test flights, but after flight testing, Boeing quietly, (as in, didn't communicate the change to others), increased the MCAS response rate from 0.6deg ND per application to 2.5deg ND per application and didn't tell anyone who would need to have known, (like pilots).

Though Boeing continues to state that MCAS was not designed as a "stall prevention" system, if that adjustment in HS trim speed turned MCAS into a stall-prevention system from merely a "feels-the-same-for-common-type purposes" system then Boeing has a significant problem and so does the FAA. I think this is why we are beginning to see these comments.

From AC25-7D:

42.1.5.2.2 To ensure that inadvertent operation of the stall identification system does not jeopardize safe flight, and to maintain crew confidence in the system, it should be shown that:
 No single failure will result in inadvertent operation of the stall identification system; and
 The probability of inadvertent operation from all causes is improbable (not greater than 10-5 per flight hour).

Also, the shift in thinking concerning MCAS may be coming from the JATR, Finding 3.7A:

Joint Authorities Technical Review
Boeing 737 MAX Flight Control System
Executive Summary
____________________________________________________________________________
VI
Recommendation R3
Based on the JATR team’s observations and findings related to the certification of the B737
MAX flight control system and related interfaces, JATR team members recommend that the
FAA review the B737 MAX compliance to 14 CFR §§ 25.1329 (Flight Guidance System),
25.1581 (Airplane Flight Manual – General), and 25.201 (Stall Demonstration) and ensure
the consistent application and interpretation of regulatory guidance material for the system
safety assessment, handling qualities rating method, and conformity requirements for
engineering simulators and devices. Should there be a non-compliance, the root cause
should be identified and measures implemented to prevent recurrence.

and,

Recommendation R3.7: The FAA should review how compliance was shown for the stall
  identification system on the B737 MAX with respect to inadvertent operation due to
  single failures.
         o Finding F3.7-A: The JATR team considers that system features on the B737
            MAX might constitute a stall identification system. This system is vulnerable to
            inadvertent actuation due to a single failure, which would not meet the accepted
            guidance contained within AC 25-7C, Chapter 8, Section 228.

Edited to add:

I disagree with the use of the word, "identification" in the paragraph above. MCAS is not "identifying" an impending stall, it is responding to AoA data that indicates an impending stall. "Identifying" a potential stall is the work of the stick shaker, and any addition to that system would necessarily have to be part of the FCOM as it is a major change in the flight control system, (much the same as a stick pusher).

This is a longitudinal stability issue, one that has history.

Edited by Don Hudson
add "ND" to MCAS application direction
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As I stated before.  Boeing says its just a "feel" thing.  In practicality it is a stall protection thing.  

They parked firmly in a grey area that is becoming less and less grey as the light shines upon it.

Homerun.  I agree completely that is the 737 MAX was a clean slate design with FBW, We, Boeing and the FAA would not be having this discussion.

 

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It wasn’t just a ‘feel’ issue as compared to the NG. It was about inherent stability (or lack thereof).

At certain angles of attack, the new engine shroud appears to develop lift which reduced the back pressure required on the control column to maintain the pitch up attitude.

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and the cheese just got a little more binding.  I wonder how CUPE expects will prove the aircraft is safe?

Media Advisory - Transport Canada will have to demonstrate that the Boeing 737 Max are safe to fly Français

 
Logo: Canadian Union of Public Employees (CUPE) (CNW Group/Canadian Union of Public Employees (CUPE))

NEWS PROVIDED BY

Canadian Union of Public Employees (CUPE) 

Nov 05, 2019, 10:37 ET


OTTAWA, Nov. 5, 2019 /CNW/ - The unions representing flight attendants at Air Canada, Sunwing and WestJet stand in solidarity with the American flight attendant unions who expressed safety concerns about the Boeing 737 Max flying again soon. The Air Canada Component of CUPE (Air Canada Mainline and Air Canada Rouge), CUPE local 4055 (Sunwing), and CUPE local 4070 (WestJet, WestJet Encore and Swoop) are calling on Transport Canada to take its responsibility in ensuring the safety of these aircraft.

The safety of passengers and crew must always come first. The federal government's decision to ground the Boeing 737 Max in Canada was the right thing to do. Given the record of Boeing and the Federal Aviation Administration in that file, it will now be up to Transport Canada to provide assurances that these aircraft are fully compliant and safe for our members and the travelling public.

Like the US flight attendant unions, CUPE must be consulted before Transport Canada makes the decision to allow the Boeing 737 Max to fly in our skies again. We need access to all the information required to assess the safety of these aircraft. The highest possible safety standards will be called for to avoid another tragedy. Simply stating these aircraft are safe does not make it so.

Air Canada, Sunwing, and WestJet are the three Canadian airlines operating the Boeing 737 Max. CUPE represents more than 13,000 flight attendants working at those airlines.

SOURCE Canadian Union of Public Employees (CUPE)

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23 minutes ago, anonymous said:

Awesome...I wonder if CUPE will hire external consultants or stick with their internal experts??

I imagine they will have lots of help.

Tuesday, November 5, 2019 Posted by Travelweek Group

OTTAWA — Flight attendants on both sides of the U.S.-Canada border are standing in solidarity over safety concerns about the Boeing 737 Max.

The unions representing flight attendants at Air Canada, Sunwing and WestJet are showing their support for their American counterparts, who last week expressed their concerns about the troubled aircraft. In a letter dated Oct. 30, American Airlines’ flight attendants union, which represents 28,000 employees, said they are refusing to “walk onto a plane that may not be safe and are calling for the highest possible safety standards to avoid another tragedy.”

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Transport Canada was among the last of the world's regulators to acknowledge that the 737 MAX needed to be grounded.  As poorly worded as the above bulletin is, it's appropriate for CUPE to remind TC of its responsibility to ensure that the aircraft is safe before allowing it to return to service.

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