Go Back  PPRuNe Forums > Flight Deck Forums > Rumours & News
Reload this Page >

Ethiopian airliner down in Africa

Rumours & News Reporting Points that may affect our jobs or lives as professional pilots. Also, items that may be of interest to professional pilots.

Ethiopian airliner down in Africa

Old 13th Mar 2019, 20:04
  #1161 (permalink)  
 
Join Date: Jun 2001
Location: Rockytop, Tennessee, USA
Posts: 4,714
FAA Emergency Grounding Order:

https://www.faa.gov/news/updates/med...ency_Order.pdf
Airbubba is online now  
Old 13th Mar 2019, 20:04
  #1162 (permalink)  
 
Join Date: Mar 2010
Location: Often in Jersey, but mainly in the past.
Age: 74
Posts: 5,085
Originally Posted by rog747 View Post
oops ... should have noticed that from today's paper. <embarrassed>
MPN11 is online now  
Old 13th Mar 2019, 20:05
  #1163 (permalink)  
 
Join Date: Jan 2008
Location: Reading, UK
Posts: 9,793
Originally Posted by Airbubba View Post
Updated grounding advisory:


That makes no sense. WTF is a "B738 MAX" ?
DaveReidUK is offline  
Old 13th Mar 2019, 20:08
  #1164 (permalink)  
 
Join Date: May 2010
Location: PLanet Earth
Posts: 778
Originally Posted by whitefriars View Post
Quote:
American air safety experts are trying to persuade their Ethiopian counterparts not to send the flight data to crash investigators in London, The Wall Street Journal reported. Instead, they want it examined by the National Transportation Safety Board in the United States.
Wow!
That's bordering on all-out National panic of losing their big aircraft manufacturer. Wouldn't have expected the Panic going that far and reaching formerly largely independent Organisations (NTSB) in the US.
So far I had not really been concerned the US would go from Template Democracy to Bananas Republic in just one Presidency. Seeing this I start scratching my head...
henra is offline  
Old 13th Mar 2019, 20:08
  #1165 (permalink)  
 
Join Date: Jan 2006
Location: Gatwick
Posts: 105
Originally Posted by AndyJS View Post
Trump has just made the FAA look very very stupid by doing their job for them.
That takes some doing.
bbrown1664 is offline  
Old 13th Mar 2019, 20:09
  #1166 (permalink)  
 
Join Date: Jul 2004
Location: Netherlands
Posts: 587
Well my dear fellow Ppruners,

Perhaps this is the day that we, as an aviation resource site, have caused the global grounding of an aircraft type. I believe that the discussion that was/is going on here, and the raised concerns by some very knowledgeable experts (between some questionable commenters) has provided the world the leverage that was necessary.

Sometimes it is better to be prudent. Maybe this is it.

I am looking forward to the FAA “new evidence” that they mentioned.
fox niner is offline  
Old 13th Mar 2019, 20:10
  #1167 (permalink)  
 
Join Date: Jan 2006
Location: Gatwick
Posts: 105
Now Boeing have joined the party
https://www.bbc.co.uk/news/business-47562727
bbrown1664 is offline  
Old 13th Mar 2019, 20:12
  #1168 (permalink)  
 
Join Date: Feb 2000
Location: 500 miles from Chaikhosi, Yogistan
Posts: 3,411
Originally Posted by AndyJS View Post
Trump has just made the FAA look very very stupid by doing their job for them.
I would suggest that he got wind of the FAAs intentions after they received some data and announced it just before them.
compressor stall is offline  
Old 13th Mar 2019, 20:13
  #1169 (permalink)  
 
Join Date: Jan 2019
Location: Belfast
Posts: 35
FCeng84FCeng84 , 12th Mar 2019 22:26
Quote:
Originally Posted by hans brinker
You would be making things worse by adding power. To get out of a high AOA, you lower the nose before adding power.....
Hans - your patience is amazing. You are correct about the relationship between 737MAX engines and need for MCAS. It has nothing to do with the thrust pitching moment!!!

There is a cert requirement that as AOA increases, the nose up pilot command required must not decrease. This is demonstrated at fixed thrust levels so there is no change in thrust pitching moment. The 737MAX issue here that gives rise to the need for MCAS is that as AOA increases the lift provided by the engine cowling that is so large and mounted so far forward of the wing causes a nose up pitching moment that results is a decrease in the column pull needed to maintain a steady positive AOA rate. That characteristic is not compliant with the requirements. MCAS comes active during this maneuver putting in nose down stabilizer that must be countered by the column. The net effect of engine cowling lift and MCAS nose down stabilizer as AOA increases is that the column needed to complete the maneuver does not decrease part way through the range of AOA for which characteristics must be demonstrated. 737MAX without MCAS fails the cert demo. 737MAX with MCAS passes the cert demo.
I know there's little evidence at this stage for this tragedy, but to elaborate and hypothesise about MCAS function:

1. MCAS activated by errant AoA vane data. (This same data may also lead to warnings such as stall etc.)

2. So, by the time you run through checklist, source the problem and stop the MCAS from further inputs by flicking the Stab trim cutout, the stab is already at X° nose down.

3. At relatively low speed you're able to manage this by pulling back on the yoke, and the now fixed stab angle may even go unnoticed and forgotten about for a while

4. Additional engine power may already have been applied, but, if not, you do so now as you need some height, especially with advancing terrain and the loss of altitude that you'd suffered.

5. The effects of the engine cowling on aerodynamics, as stated in the comment above, helps lift, as does the thrust moment created by the engines

6. You think you have the problem somewhat under control compared to the situation you were in a minute ago. You've now been able to climb and seem to have relatively stable manual control.

7. Now you're at Y feet, (still with X° nose down stab trim) with an increased airspeed of Z, up until now has been controllable due to your elevator inputs being assisted by thrust moment and engine aerodynamics, but, at this new increased airspeed and increased altitude the yoke is becoming even more difficult to keep holding back. The stab is still in the same X° nose down it was when you switched the cut-outs, and up until now you mightn't have thought about it because you'd disabled it- in accordance with the checklist.

8. You think about returning and getting this back on the ground

9. Once you level off, or even before then, with that stab STILL at X° nose down (now with a much higher airspeed component) there's only one place you're going. Once this vertical direction change has momentum there's now no chance, no elevators in the world are going to help you.

Look at the memory item for stab runaway- i.e.- not told to manually wind back trim wheel, the instruction is to "grab and hold".

All this could be caused by one errant sensor? Madness that it was certified.

Last edited by positiverate20; 13th Mar 2019 at 22:20.
positiverate20 is offline  
Old 13th Mar 2019, 20:15
  #1170 (permalink)  
 
Join Date: May 2004
Location: Toronto, Canada
Age: 68
Posts: 44
Issued by whom?

<pedant mode> A number of PPRuNe posters and news outlets have said that Trump has issued an emergency order. Perhaps I'm not reading the right news, but I see only that Trump has said that "we" and "the FAA" will issue an emergency order, and I see that the FAA has said, "The FAA is ordering the temporary grounding of Boeing 737 MAX aircraft..." - no emergency order from the White House per se. </pedant mode>
boaclhryul is offline  
Old 13th Mar 2019, 20:16
  #1171 (permalink)  
 
Join Date: Feb 2019
Location: In the clouds
Posts: 1

FAA chief says data aligns Ethiopia flight data to Lion Air accident

From CNN's Greg Wallace
Speaking with reporters on a conference call, acting FAA Administrator Daniel Elwell said the grounding of the 737 Max 8 and 9 will remain in effect pending new information including from the flight data recorder and voice recorder.

“Since this accident occurred we were resolute that we would not take action until we had data,” Elwell said.

“That data coalesced today.” Elwell said the new data was "added fidelity -- missing pieces that we did not have prior to today." It aligned the Ethiopian flight data to the Lion Air incident.

Elwell declined to guess how long the grounding would last but he said he hoped to keep it "as short as possible."

“I can’t and I don’t want to hazard a guess as to how long. My hope is that the FAA, the carriers, the manufacturer, that all parties will work very hard to make this grounding as short as possible so that these airplanes can get back up into the sky," he said.
BAM279 is offline  
Old 13th Mar 2019, 20:19
  #1172 (permalink)  
 
Join Date: Oct 2009
Location: Spain and Gibraltar
Posts: 21
Those airlines that have ordered the 737 MAX versions, can they just cancel their orders, or are they stuck with them probably with a 'No get out cause'??
Nil by mouth is offline  
Old 13th Mar 2019, 20:23
  #1173 (permalink)  
 
Join Date: Jun 2001
Location: Rockytop, Tennessee, USA
Posts: 4,714
Originally Posted by Tech Guy View Post
If one presumes the grounded aircraft will be towed to an unused corner of their respective airports rather than taking up valuable space on the apron, or at gates, would preventative preparations be made for an extended grounding? How long can the aircraft be grounded for in a "cold" state without requiring extensive checks and maintenance prior to returning to service?

Would the airports be levying a "storage charge"?
It looks like ferry permits will be issued to move the aircraft for maintenance, storage or modification.

From the Order:




Airbubba is online now  
Old 13th Mar 2019, 20:23
  #1174 (permalink)  
 
Join Date: Oct 2009
Location: Spain and Gibraltar
Posts: 21
I just read this https://www.bbc.com/news/business-47562727

Last edited by Nil by mouth; 13th Mar 2019 at 20:28. Reason: Already posted
Nil by mouth is offline  
Old 13th Mar 2019, 20:24
  #1175 (permalink)  
 
Join Date: Sep 2000
Location: Planet Earth
Posts: 274
Is it is true that ET are sending the FDR and CVR to Europe instead of the USA ?
6000PIC is offline  
Old 13th Mar 2019, 20:27
  #1176 (permalink)  
 
Join Date: Nov 2010
Location: Atlanta
Age: 51
Posts: 250
Originally Posted by Nil by mouth View Post
Those airlines that have ordered the 737 MAX versions, can they just cancel their orders, or are they stuck with them probably with a 'No get out cause'??
https://www.boeingstore.com/pages/return-policy

/S
hans brinker is offline  
Old 13th Mar 2019, 20:28
  #1177 (permalink)  
 
Join Date: Jan 2008
Location: Netherlands
Age: 41
Posts: 118
Originally Posted by cynar View Post
yeah, what's this new evidence? what do we know today that we didn't know Monday?
They probably confirmed that the aircraft has had to come down in a near vertical nose down attitude, similar to the Lion air case.
procede is online now  
Old 13th Mar 2019, 20:31
  #1178 (permalink)  
 
Join Date: Jun 2001
Location: Rockytop, Tennessee, USA
Posts: 4,714
Statement from ALPA (United's pilot union, the American Airlines pilot union is APA, Southwest's is SWAPA):



Airbubba is online now  
Old 13th Mar 2019, 20:33
  #1179 (permalink)  
 
Join Date: Aug 2013
Location: Washington.
Age: 69
Posts: 438
Originally Posted by SLFinAZ View Post
Amazing reading.

Basically what it confirms is that for competent well rested crews the potential MCAS issues are a minor speed bump. Doesn't mean that it isn't a very real issue but the bottom line specific to Lion Air is simple and compelling....crew error. As for the current tragedy we really don't know enough but it doesn't have any of the trim related oscillation seen in Flight 610...

At some point the various regulatory agencies will need to figure it out.
FAA needs to require Boeing to remove this "speed bump." That some alert and competent pilots are able to overcome it is wonderful, but still an insufficient level of safety as attested to by hundreds of fatalities. If it turns out that AoA sense system failures are the root cause of the MCAS behavior, then the AoA sensor system needs to be made more reliable (higher integrity), in keeping with potential catastrophic failures.
GlobalNav is offline  
Old 13th Mar 2019, 20:37
  #1180 (permalink)  
 
Join Date: Apr 2015
Location: Under the radar, over the rainbow
Posts: 45
Originally Posted by hans brinker View Post
Boeing Store Return Policy (link)

/S
What percentage do you think will choose store credit over refund?
OldnGrounded is offline  

Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

Copyright © 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.