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Author Topic: Boeing 737 MAX family  (Read 20693 times)

Offline Arjen

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Re: Boeing 737 MAX family
« Reply #105 on: April 07, 2019, 09:37:26 am »
tomcatvip: I find many of your contributions hard to understand. Of what I can understand, you appear to say that much of the responsibility for the recent 737 MAX crashes lies with the mechanics who serviced and with the pilots who flew both aircraft. On the other hand, the FAA - after some nudging - and many other authorities who certify aircraft for passenger services are considering inherent weaknesses in the 737 MAX design as a likely explanation to such an extent that they have stopped 737 MAX operations. I do not know your qualifications, but I have just enough trust in the FAA - even after the shambles they made of the 737 MAX's certification - to assume something is seriously wrong with the 737 MAX and with the way pilots are trained to fly it.

And do try to be clearer in your contributions.
« Last Edit: April 07, 2019, 09:45:33 am by Arjen »

Offline steelpillow

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Re: Boeing 737 MAX family
« Reply #106 on: April 07, 2019, 10:19:15 am »
Joining this thread for the first time, I am astonished to find people looking to pick holes in pilot performance, flap settings and other distractions. WTF?

Boeing themselves have at last admitted that they messed up and have apologised to the families of the victims. Although the final analysis is yet to come in, preliminary reports from both the LionAir and Ethiopian investigations conclude that the crews tried all the right things and that it was the MCAS system (or something that acts very like it) that was to blame. Failed sensors, software bugs and cutbacks on warning indicators and pilot training - all self-certified by Boeing with the blessing of the FAA - conspired to cause two fatal crashes and a host of other reported incidents. The update recently announced by Boeing addresses all the issues so far identified:
  • The MCAS will now poll both AoA sensors simultaneously and not operate unless both agree.
  • The MCAS will operate the elevator with less authority than the trim wheel, allowing crews to counteract it.
  • The MCAS will be less inclined to repeat its actions over and over just because the pilots are fighting it.
  • A warning indicator that has until now been an optional extra will be retro-fitted as standard.
  • Pilots will actually be trained in the system and its foibles before being sent to fly it.
Other than waiting to see if more Boeing gaffes might surface, do we really need to look any further?
« Last Edit: April 07, 2019, 10:23:03 am by steelpillow »
Cheers.

Offline Arjen

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Re: Boeing 737 MAX family
« Reply #107 on: April 07, 2019, 10:46:34 am »
Boeing admitting fault. I wonder whether THAT will convince people picking holes. Of which I count one.

Offline Antonio

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Re: Boeing 737 MAX family
« Reply #108 on: April 07, 2019, 10:47:12 am »
Dear sirs, since the thread has mutated its main subject from plain "unbuilt projects" to the tragedy in which the 737 MAX is now involved, please try to avoid personal hostility and conflictive posts. Thanks

Offline steelpillow

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Re: Boeing 737 MAX family
« Reply #109 on: April 07, 2019, 11:01:30 am »
Antonio, I take your point and thank you. I would suggest that the not-yet-operational fixes recently announced by Boeing are relevant, and it is acceptable to query their background. Of course personal attacks should not be permitted (though sadly, some against myself have slipped through in the past), but criticism of stated opinions has to be fair game if the truth is to out. If I stray the wrong side of decency, I trust that our Admins will bring me up sharp.
Cheers.

Offline TomcatViP

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Re: Boeing 737 MAX family
« Reply #110 on: April 07, 2019, 02:09:38 pm »
As a end note to that digression (and i will refrain to add more until we have some new material), my opinion is very much in concern with:

   - The passengers that had to endure an horrible agony and trauma (including physical)  - see what happened to teh public in that 747 discussed earlier
   - The pilots, the ones that dare to bring back safely a plane compromising somewhat their career with an aborted flight.

Best to all

TC
« Last Edit: April 07, 2019, 02:11:18 pm by TomcatViP »

Offline Richard N

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Re: Boeing 737 MAX family
« Reply #111 on: April 11, 2019, 01:29:08 pm »
The latest in a series of videos about 737 Max incidents by a current airline pilot.  The full list here: 




Offline Grey Havoc

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The sole imperative of a government, once instituted, is to survive.

Offline TomcatViP

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Re: Boeing 737 MAX family
« Reply #113 on: April 14, 2019, 06:50:12 am »
Ethiopian Crash Data Analysis Points To Vane Detachment

Quote
[...] the aircraft’s left angle-of-attack (AOA) sensor vane detached seconds after take-off and that, contrary to statements from the airline, suggests the crew did not follow all the steps for the correct procedure for a runaway stabilizer.

Detailed analysis of the FDR trace data shows that approximately six seconds after liftoff was signaled by the weight-on-wheels switch data, the data indicate the divergence in angle-of-attack (AOA) and the onset of the captain’s stick-shaker, or stall warning. Almost simultaneously, data shows the AOA sensor vane pivoted to an extreme nose-high position.

This, says one source, is a clear indication that the AOA’s external vane was sheared off—most likely by a bird impact. The vane is counter-balanced by a weight located inside the AOA sensor mounting unit, and without aerodynamic forces acting on the vane, the counterweight drops down. The AOA sensor, however, interpreted the position of the alpha vane balance as being at an extreme nose-high angle-of-attack.

IMOHO expressed earlier, a sensor experiencing a catastrophic failures should have embedded elementary systems that prevent it to send an erroneous feed to the aircraft systems. In that case, the loss of counterbalancing could probably have been detected by a simple torque limiter (a cheap device) that would have turned mechanically the sensor off.

Source:
AviationWeek.com
« Last Edit: April 14, 2019, 07:34:30 am by TomcatViP »

Offline Joe Warner Cherrie (TsrJoe)

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...'excuse me mister, is that plane for real'...!!!

IPMS (UK) 'Project Cancelled' SIG. co,co-ordinator
IPMS (UK) 'TSR-2', 'Cold War' & 'What-if' SIG. Member

Offline Richard N

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Re: Boeing 737 MAX family
« Reply #115 on: April 15, 2019, 12:50:45 pm »

Offline sublight is back

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Re: Boeing 737 MAX family
« Reply #116 on: April 15, 2019, 01:55:51 pm »
The design decisions were just stupid, and while good pilots can work around that, they shouldn't have to. This in not going to go away. Their only stroke of luck from a litigation point of view is that none of the domestic airlines crashed one. As long as that doesn't happen, they can Just take the 393 Airframes, convert them to cargo planes.

But the current CEO probably wants to leave with his shares intact, so he'll kick that can down the road.

Offline Antonio

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Re: Boeing 737 MAX family
« Reply #117 on: April 16, 2019, 04:19:04 am »
Please, avoid political posts...