News Ethiopian 737 crashed on way to Kenya, 157 people on-board

IronRain

The One and Only (AFAIK)
Administrator
Moderator
Donator
Joined
Oct 11, 2009
Messages
3,391
Reaction score
200
Points
103
Location
Utrecht
Website
www.spaceflightnewsapi.net
An Ethiopian Airlines Boeing 737 passenger jet has crashed on a flight from Addis Ababa to Nairobi.
The flight is believed to have had 149 passengers and eight crew members on board, the airline says.
A spokesman said the crash happened at 08.44 local time on Sunday, shortly after take-off from the Ethiopian capital.
In a statement, the airline said that search and rescue operations were under way.
It did not provide details on the number of casualties.
"Ethiopian Airlines staff will be sent to the accident scene and will do everything possible to assist the emergency services," the airline added.


Sources:
- https://www.bbc.com/news/world-africa-47513508
 

Wolf

Donator
Donator
Joined
Feb 10, 2008
Messages
1,083
Reaction score
2
Points
38
Location
Milan
It's the second 737-800 MAX (after the Lion Air one) let's see what the investigation report will come up with; really hope the two accidents are not related.
 

MaverickSawyer

Acolyte of the Probe
Joined
Apr 11, 2011
Messages
3,919
Reaction score
3
Points
61
Location
Wichita
Hmm. This one's a -8MAX. Wasn't the LionAir one a -10MAX? If it was, the cause cannot be the same, as the -10 has some serious changes to the pitch controls to keep handling the same.
 

Urwumpe

Not funny anymore
Addon Developer
Donator
Joined
Feb 6, 2008
Messages
35,872
Reaction score
390
Points
173
Location
Langendernbach
Hmm. This one's a -8MAX. Wasn't the LionAir one a -10MAX? If it was, the cause cannot be the same, as the -10 has some serious changes to the pitch controls to keep handling the same.


Well - there could still be common components....
 

Urwumpe

Not funny anymore
Addon Developer
Donator
Joined
Feb 6, 2008
Messages
35,872
Reaction score
390
Points
173
Location
Langendernbach
The system that is currently believed to be responsible for the loss of the LionAir flight is unique to the -10MAX.


Still, that doesn't mean that there could be a common component of both versions that responsible for THIS crash. It just means that it is less likely (but not unlikely) that one cause of the first crash also applies to this one. Remember, planes don't crash because of just one failure or error.
 

dbeachy1

O-F Administrator
Administrator
Moderator
Addon Developer
Donator
Beta Tester
Joined
Jan 14, 2008
Messages
8,843
Reaction score
784
Points
203
Location
VA
Website
alteaaerospace.com

crisk73

New member
Joined
Mar 8, 2013
Messages
17
Reaction score
0
Points
0
Location
Venezia
Lion Air 610 was a Max 8 as well, anyway all Maxes have the same avionics and systems including the MCAS which was found to be what triggered the events chain in the LionAir accident.
Here, looking at the altitude vs. speed and v/s profile of today's crash on FR24 it appears to be pretty much similar even though it is too early to say.
 

Wolf

Donator
Donator
Joined
Feb 10, 2008
Messages
1,083
Reaction score
2
Points
38
Location
Milan
The system that is currently believed to be responsible for the loss of the LionAir flight is unique to the -10MAX.

Could you give some details of this unique system? AFAIK the whole MAX “family” has the same exact system (like the NG family: -700/-800/-900 have the same platform)

---------- Post added 03-11-19 at 10:37 AM ---------- Previous post was 03-10-19 at 10:02 PM ----------

It looks like the crew requested an immediate turnback to the airfield due to airspeed unreliable and problems controlling the aircraft. Airspeed unreliable is a very bad thing but there is checklist designed to keep the airplane safely in the air, so the loss of control problem may or may not be related to the wrong instrument information regarding the speed.
Meanwhile it looks like China grounded all the 737 MAX (maybe a bit of a rushed decision, though it could be the correct one)
 

Gingin

Member
Joined
Feb 5, 2015
Messages
256
Reaction score
4
Points
18
Location
City of Light
Last edited:

Linguofreak

Well-known member
Joined
May 10, 2008
Messages
4,156
Reaction score
54
Points
73
Location
Dallas, TX
I have heard that China has grounded the 737 MAX.

The impression I get from the Wikipedia article on the LionAir flight is a combination of poor maintenance and a design issue that does not tolerate poor maintenance. Specifically, a stick pusher system that can suffer false alarm activations when air data sensors are poorly maintained.

China's action in this case is probably half realpolitik ("Ground the scaaaary daaaangerous American aircraft!") and half genuine safety concern. In general, it can probably be anticipated that Western nations and nations with good relationships with the US will cave to Boeing lobbying and keep the 737 MAX flying unless they have very serious concerns about the maintenance standards of their domestic airlines and feel they can admit it without compromising their national pride, or unless the FAA grounds the aircraft. Nations hostile to the US will likely ground the aircraft to stick it to the Americans.

The correct action is probably to perform a sober, apolitical analysis of the maintenance standards of domestic airlines that is neither trigger happy about grounding nor afraid to ground the aircraft if maintenance standards are found wanting.
 

crisk73

New member
Joined
Mar 8, 2013
Messages
17
Reaction score
0
Points
0
Location
Venezia
Agree, but it's difficult to talk about maintenance in both cases of four months old machines..
Ok, Indonesian pilots were not trained enough to take the right countermeasures, but what happened here? Shouldn't the experienced pilot (12 yrs of 737 plus aware of the Indonesian accident) know what to do?
 

Urwumpe

Not funny anymore
Addon Developer
Donator
Joined
Feb 6, 2008
Messages
35,872
Reaction score
390
Points
173
Location
Langendernbach
The impression I get from the Wikipedia article on the LionAir flight is a combination of poor maintenance and a design issue that does not tolerate poor maintenance. Specifically, a stick pusher system that can suffer false alarm activations when air data sensors are poorly maintained.

That is a too easy conclusion - Lion Air isn't known for poor maintenance and Ethiopian Airlines is especially notable in Africa for their modern fleet and good maintenance. Especially in this case: The airliner was delivered to the airline in November 2018. Its just a few months old.

In the case of Lion Air, a faulty pitot sensors was replaced before the final two flights, because earlier flights reported similar issues. It is not known if it was incorrectly calibrated then, but the aircraft already had problems with altitude and airspeed that resulted in the maintenance. The next flight needed to try three different off-normal procedures until the problems had been under control. Not sure what the final flight attempted in the final 10 minutes, but the crew was constantly correcting the automatic nose-down trim, while the aircraft was overspeeding.

I am not sure, if the issue is really caused by maintenance of the pitot sensors. But that a system like the MCAS only makes use of ONE pitot sensor sounds like a terrible joke to me. Also the almost open-loop behavior of MCAS is pretty disturbing - it doesn't care about the control inputs or actual flight condition, just Mach number and AOA.

The whole story about how MCAS came into the 737 MAX sounds like "evil hack" - as fix for the torques produced by the new engine position.
 

Marijn

Active member
Joined
Mar 5, 2008
Messages
638
Reaction score
44
Points
28
Location
Amsterdam
...the crew was constantly correcting the automatic nose-down trim, while the aircraft was overspeeding.

Can't they just switch the autopilot off and take manual control? Why should you keep fighting a system if you can disable it?
 

Gingin

Member
Joined
Feb 5, 2015
Messages
256
Reaction score
4
Points
18
Location
City of Light

Ripley

Tutorial translator
Donator
Joined
Sep 12, 2010
Messages
2,957
Reaction score
183
Points
78
Location
Rome
Website
www.tuttovola.org
...Why should you keep fighting a system if you can disable it?
Good question, but this is just one link in the error chain.
Maybe you "keep fighting" it because you trust in it and you're sure that it will be able to recover the situation.
Meanwhile, said situation gets worse and worse...

I don't know what this MCAS system is, I'm reading about it now.
 
Last edited:

martins

Orbiter Founder
Orbiter Founder
Joined
Mar 31, 2008
Messages
2,349
Reaction score
17
Points
0
Website
orbit.medphys.ucl.ac.uk
[...] is probably half realpolitik ("Ground the scaaaary daaaangerous American aircraft!") and half genuine safety concern. [...]

Is this a fake Chinese accent I am hearing there? :huh:

An interesting use of the word "realpolitik", by the way. I think I heard it first in the 80s in connection with the German Green party when a rift appeared between the more fundamentalist wing trying to preserve the party ideology (the "Fundis") and the "Realpolitiker" (the "Realos") trying to compromise to make the program more mainstream and improve the electability and the chance of powersharing.

A quick search for "realpolitik" comes up with "a system of politics or principles based on practical rather than moral or ideological considerations", which sounds about right but seems almost exactly the opposite of your use of the word.
 

Urwumpe

Not funny anymore
Addon Developer
Donator
Joined
Feb 6, 2008
Messages
35,872
Reaction score
390
Points
173
Location
Langendernbach
Can't they just switch the autopilot off and take manual control? Why should you keep fighting a system if you can disable it?

Because you need to know that this system causes the problems. The preliminary report of the Lion Air event suggests that this is not so obvious.

Also completely disabling the MCAS takes more action, pressing the button on the stick or moving the trim wheels only disables it temporarily. A software patch by Boeing is planned to improve this behavior.

This article here shows pretty well already in the beginning, what is wrong with MCAS and what I meant with "open loop-like behavior":

https://www.satcom.guru/2018/11/737-mcas-failure-is-option.html
 
Last edited:

jedidia

shoemaker without legs
Addon Developer
Joined
Mar 19, 2008
Messages
9,578
Reaction score
395
Points
173
Location
between the planets
An interesting use of the word "realpolitik", by the way.

Indeed, the word seems misapplied. We generally use it to describe politics focused on compromise rather than populism. Taking an option that does not live up to your ideals because in reality, it's the best you're going to get.
It is often applied with a negative conotation, though. Like for example "we really should do something about global warming quickly, but Realpolitik is making it impossible" or somesuch.
 
Top