Another brand new 737 Max crashes

[stomachmonkey]

Originally Posted by flipper35

To go a little further, the previous cars you owned were all similar with 4 channel ABS an you trained in the car on a race track and on your mental checklist is what to do if an ABS sensor goes bad triggering ABS on one wheel - The old737 NG. Now you have a new car but you don't know it has stability control, the 737 Max 8/9 and the ABS triggers oddly. What is your first thought?

Boeing marketed this plane as something that only needed 2-3 hours of ground training but included a system that apparently very few if any pilots were aware of.

I had to go to CA last month, was up in the mountains, Yosemite area.
Coming down the mountain its cold, hovering near freezing, raining, just miserable.
The rental car was all over the place, felt almost like it was either hydroplaning or hitting patches of black ice, almost.

Fought with it for an hour till I got to a lower altitude where it was warmer and dry but the thing is still driving the same way and finally the light bulb went off.

Whenever I have the room I will use up the entire road, drive in two lanes, whatever is the natural line.

Turns out the rental car had lane departure assist, if it detects you crossing the line it counter steers. No indication it had that feature and no indication it had been enabled.

Despite 40 years of driving experience I spent a stressful hour fighting the car, which was only doing what it was supposed to be doing, because I was not aware it was supposed to be doing what it was doing.

Found the toggle and turned that **** off.

[flipper35]

MCAS was designed to make the Max feel the same in its flight characteristics as the NG so there would be minimal differences in the aircraft handling qualities as far as the pilot was concerned specifically so there would not have to be type specific training.

To apply it to your lane departure case, the car would be activly trying to drive you off the road even though you are trained to drive in the center all the time. But you were trained how to disconnect the electric power steering in previous cars in case it acted up even though the previous did not have lane departure. It doesn't matter what system is causing the malfunction, the end result is you pull power to the control that is responsible for the movement.

[flipper35]

Aside from that, the point I was trying to make, if there is a sensor mismatch would a warning light tell you what system to turn off?

[stomachmonkey]

Originally Posted by flipper35

Aside from that, the point I was trying to make, if there is a sensor mismatch would a warning light tell you what system to turn off?

Maybe, if you were aware the system was there to begin with.

With respect to the car, some indicator that a system was active would have helped. Cars with TCS indicate when it's enabled / disabled.

Which I guess is the real point, not knowing it was there.

[javadog]

Originally Posted by flipper35

Aside from that, the point I was trying to make, if there is a sensor mismatch would a warning light tell you what system to turn off?

If you knew what you were doing. Here's the airworthiness directive issued by the FAA after the Lion Air crash:

https://rgl.faa.gov/Regulatory_and_Guidance_Library/rgad.nsf/0/83ec7f95f3e5bfbd8625833e0070a070/$FILE/2018-23-51_Emergency.pdf

[flipper35]

Since the Ethiopian captain had not been in a 737 MAX sim, would he have known what to do had he those extra instruments?

Since there was so much news about the Lion Air crash, should he have not know to turn the electronic trim off?

I think Boeing was stupid to rely on one sensor when there is already redundancy available. I think they should have mentioned the new planes had stability control, but the pilots should know how to turn off the stab trim regardless of which system is triggering the stab trim.

[flipper35]

On thing keeps sticking in my head with the Ethiopian crash. The transponder cut off close to 9000' altitude.

[Eric Coffey]

Originally Posted by beepbeep

...so if I get it right, Boeing extended 60's airframe in order to compete with hot-selling A320NEO without making costly new design, mended aerodynamic controlability issues with badly designed "FBW", self-certified the system (on basis of wrong info given to FAA?).
And then they told nothing to pilots about the system until planes started falling out from the sky...And the failure mode of system itself is such that it needs observant pilot to recognize the issue and flip correct switch?

No, not really. Auto-trim systems have been a "thing" on the 737 for a very long time. Both STS (speed trim) and MTS (Mach trim). The MCAS system on the newer MAX variants is basically like STS 2.0. While I agree that all pilots/airlines should be made aware of even minor changes to flight control systems, the protocol for dealing with a faulty MCAS system has (ultimately) remained unchanged.

Further, I would hope that ANY 737 driver would be an "observant pilot" and be able to deal with an issue for which the procedure is a mandated memory-item.

Further still, The A320NEO has had it's own share of problems, including multiple in-flight engine failures. Not to mention serious additional maintenance issues that have resulted in a high "out of service" (grounding) rate.

Ask Lufthansa how they are liking their recent NEOs deliveries...

[flipper35]

Yeah, but you don't see Airbus pilots riding a stall into the water. Oh wait.

Anyone can allow a plane to crash if they panic. Some pilots are natural fliers, others know only how to deal with things based on rote memorization. If it falls outside the bounds of what they have memorized they fall apart. Remember the old adage about C students still becoming doctors? Pilots too.

[javadog]

Originally Posted by flipper35

On thing keeps sticking in my head with the Ethiopian crash. The transponder cut off close to 9000' altitude.

I don't recall the exact number but I think the crash site was at an elevation over 8,000 ft.

[flipper35]

Well that could explain it.

[flipper35]

Interesting theory.

https://leehamnews.com/2019/03/22/bjorns-corner-the-ethiopian-airlines-flight-302-crash-part-2/

[beepbeep]

It is nice read but it is not like compressibility is new thing. it is a known factor on all airframes. The real question IMHO is how MCAS got certified in the first place.

This is also an interesting read (albeit a tad jingoistic here and there):
https://drive.google.com/file/d/1249KS8xtIDKb5SxgpeFI6AD-PSC6nFA5/view

[red-beard]

Originally Posted by flipper35

Since the Ethiopian captain had not been in a 737 MAX sim, would he have known what to do had he those extra instruments?

Since there was so much news about the Lion Air crash, should he have not know to turn the electronic trim off?

I think Boeing was stupid to rely on one sensor when there is already redundancy available. I think they should have mentioned the new planes had stability control, but the pilots should know how to turn off the stab trim regardless of which system is triggering the stab trim.

That was a software mistake. It should have been two out of two voting instead on one out of two voting. The idea behind the warning light was that if the two disagreed, the light would come on. I do not think Boeing knew they had programmed one out of two voting.

[flipper35]

I thought it was one out of one voting for MCAS. I think on some of the older 737 models they used the left side sensor for part of the systems and the right for others and only both for a limited number for some reason.

[javadog]

There are two AOA sensors on the Max 8, each feeds into a flight control computer on its side of the aircraft. The plane uses one at a time, which alternates with each successive flight.

[sammyg2]

Not really related, but funny in a sad way:

British Airways flight takes off in wrong direction, lands 525 miles away from destination
By Alexandra Deabler


A British Airways flight bound for Germany ended up in Scotland because of a paperwork mix-up, the airline confirmed to Fox News.


The 525-mile mistake happened Monday, after an incorrect flight plan was filed, changing the flight path of the London, England flight from Düsseldorf, Germany – where it was originally scheduled to land – to Edinburgh, Scotland.


Passengers on the hourlong flight did not realize they landed in a different country until the pilot made an announcement welcoming them to Edinburgh, BBC reported.


The flight was scheduled to go to Germany when it flew to Scotland due to a paperwork mix-up.


Passenger Sophie Cooke told the BBC that those on the flight thought the pilot was joking, until flight crew confirmed that they were in Scotland.

"The pilot said he had no idea how it had happened. He said it had never happened before and that the crew was trying to work out what we could do," Cooke said.


British Airways confirmed the incident to Fox News and said in a statement they were following up with German firm WDL Aviation, which operated the flight for the airline.

“We are working with WDL Aviation, who operated this flight on behalf of British Airways, to establish why the incorrect flight plan was filed,” the statement read. “We have apologized to customers for this interruption to their journey and will deal with them all individually.”


The flight was redirected to Düsseldorf two-and-a-half hours after the “involuntary stopover in Edinburgh,” turning the typical hour-and-ten minute flight into a nearly six-hour journey.

British Airways said the safety of the passengers was never “compromised.”

In other news:

NAKED MAN ATTEMPTS TO BOARD FLIGHT AT MOSCOW AIRPORT, CLAIMS NUDITY MAKES HIM MORE 'AERODYNAMIC'

https://www.foxnews.com/travel/naked-man-attempts-to-board-flight-at-moscow-airport-claims-nudity-makes-him-more-aerodynamic

[Eric Coffey]

Originally Posted by sammyg2

In other news:

NAKED MAN ATTEMPTS TO BOARD FLIGHT AT MOSCOW AIRPORT, CLAIMS NUDITY MAKES HIM MORE 'AERODYNAMIC'

https://www.foxnews.com/travel/naked-man-attempts-to-board-flight-at-moscow-airport-claims-nudity-makes-him-more-aerodynamic

Should have told him to hop out on the wing and find out...

[Jeff Higgins]

It looks like one of the AOA sensors was damaged shortly after takeoff, possibly by a bird strike or other FOD.

https://komonews.com/news/local/sensor-damage-on-ethiopian-airlines-737-max-abc-news-reports

A damaged angle-of-attack sensor may have erroneously triggered anti-stall MCAS software on board a doomed Ethiopian Airlines Boeing 737 Max jet.

ABC News reports the sensor was damaged on takeoff from a bird or foreign object sending the plane downward and eventually crashing into the ground. ABC cites two aviation sources close to the investigation.

It sounds like, with this information, they will be revisiting the Lion Air crash to determine if it may have suffered a similar fate. We do know, in their case, that they had recently performed some sort of service on the AOA sensors. It has been suspected that the service performed may have been substandard.

[javadog]

It's been reported that the Ethiopian pilots flipped the switches to disable MCAS... which sort of indicates that at least one of them recognized the problem and knew how to handle it...

...but then they flipped them back on.