Ground stop message:


https://cimg6.ibsrv.net/gimg/pprune....2980ebf535.jpg

737-max ops Jersey

https://jerseyeveningpost.com/news/2...erife-service/

If I remember AF447 correctly it was all speculation as there was no data until over a year later when the recorders were recovered. At that time, if my memory serves me right, data showed the flight crew member in the right seat was commanding pitch up with his joystick while the pilot in the left seat was either neutral or pitch down. Basic flaw of joysticks on 2 crew cockpits in that they do not provide input by feel between flight crew. Thales sensors were speculation due to failure history.

I keep looking here to see if there is data confirming why Ethiopian crashed similar to the data on Lion Air. Have I missed it? In the case of the Lion Air there was the history of the previous flight where the pilot experienced the same sensor malfunction yet flew to destination. Ethoiopian says the previous flight was normal with no write-ups. It reminds me so much of the AA DC-10 in Chicago where the action was to shoot first and ask questions later with the evidence of what happened lying on the runway. Yes, the DC-10 had many faults resulting from rushing into production but engines falling off wings was not one of them. Engines falling off wings causing the slats to retract was a design flaw.

Now the media is interviewing MAX pilots who say they have spent their time as MAX pilots terrified of their life due to control problems. How come they did not say this before? And we have Donald Trump saying airplanes today are too complex for pilots to fly. It just keeps getting worse and worse.

Trump has just made the FAA look very very stupid by doing their job for them.

Aireon FAA
 

It seems Aireon had better data than FR24 and this led to the FAA decision. This is surprising because Aireon update rate is said to be once per minute.

Updated grounding advisory:


https://cimg8.ibsrv.net/gimg/pprune....a5c18c8ba3.jpg

FAA Emergency Grounding Order:

https://www.faa.gov/news/updates/med...ency_Order.pdf

oops ... should have noticed that from today's paper. <embarrassed>

That makes no sense. WTF is a "B738 MAX" ?

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...

That takes some doing.

Now Boeing have joined the party
https://www.bbc.co.uk/news/business-47562727

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.

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>

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.

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'??