Ethiopian 737 Max 8 crash and Fallout

Well, British Airways never gives a toss about their customers to begin with so they might as well buy a dodgy aircraft type and let them die to save a few bucks...
 
Well, BA were reportedly angling for some discounted A380s towards the end of their lifecycle, but couldn't get enough of a discount. They probably tried some bottom fishing here, but with more success given the criticality of the 737 to Boeing.
 
Apparently it’s a letter of intent, not a firm order yet, and if they are converted to firm orders they’ll be assigned to Vueling, Level, and BA flights from LGW
 


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Efforts to get Boeing Co.’s BA -0.40% 737 MAX jetliners back in the air have been delayed in part by concerns about whether the average pilot has enough physical strength to turn a manual crank in extreme emergencies.
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In a flight-simulator test earlier this month, The Wall Street Journal’s Scott McCartney and pilot Roddy Guthrie, fleet captain for the 737 at American Airlines, experienced troubles in turning the wheel. As described in a June 5 article, Capt. Guthrie couldn’t move the wheel until Mr. McCartney pitched the plane’s nose down, easing some of the pressure on the wheel.
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[Capt. Chelsey “Sully”] Sullenberger told the committee that he recently experienced a recreation of the fatal MAX flights in a flight simulator. He came away from it understanding how crews could have been overwhelmed by alerts and warnings without enough time to fix the problem.
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Running out of something is how most accidents happen. Out of time, fuel, height, runway, speed.
I thought comments about the strength needed to fight the automatic trim were in the same dimension - running out of strength.
 
I thought comments about the strength needed to fight the automatic trim were in the same dimension - running out of strength.
Whilst it's about strength to a degree, the issue is that nose down trim can have more effect than nose up elevator. There comes a point where full aft elevator will not arrest the nose down motion. So, even if you were superman, holding the stick fully aft would not help.

The issue is also that the strength needed to move the manual trim wheel is beyond what is likely to be available. This was always a poor design, which is why it has disappeared from virtually every new aircraft...except for.... This may have been doable in earlier 737s, which is where we get led into a discussion about unloading the aircraft so that the trim jack has less pressure on it. But, with the 737NG, Boeing changed the design of the wheel to allow more space for the FMCs. There is some discussion about whether that was ever tested. The upshot is that whilst the NG does not have MCAS, and so is not susceptible to this form of runaway, the procedure for manual trim after a runaway in that aircraft may also be built on a house of cards.

Whilst I don't expect any regulators to demand that Boeing certify the aircraft as if it were new, I don't think that there is any doubt that it would not be certifiable under current regulations. You have to wonder whether this is a good thing given that airlines are talking about taking deliveries around 2025.
 

Seems in the simulators the 'wheel' is too easy to turn when simulating high speed.

I can guarantee you it's not easy to turn even in the simulator at high speed (>300kts). I've got my sim in the next couple of weeks and a focus part is the runaway stabiliser. I'm sure we will get a chance to have a play and try to recreate the event.
 
Boeing sued by more than 400 pilots in class action over 737 MAX's 'unprecedented cover-up'


More than 400 pilots have joined a class action against American plane manufacturer Boeing, seeking damages in the millions over what they allege was the company's "unprecedented cover-up" of the "known design flaws" of the latest edition of its top-selling jet, the 737 MAX.

This latest lawsuit filed against Boeing marks the first class action lodged by pilots qualified to fly the 737 MAX series, who have alleged that Boeing's decisions have caused them to suffer from monetary loss and mental distress since the jet's suspension.

The originating plaintiff, known as Pilot X —who has chosen to remain anonymous for "fear of reprisal from Boeing and discrimination from Boeing customers" — lodged the statement of claim on Friday, which seeks damages for them and more than 400 colleagues who work for the same airline.

In court documents seen by the ABC, the claim alleges that Boeing "engaged in an unprecedented cover-up of the known design flaws of the MAX, which predictably resulted in the crashes of two MAX aircraft and subsequent grounding of all MAX aircraft worldwide."
 
I can guarantee you it's not easy to turn even in the simulator at high speed (>300kts). I've got my sim in the next couple of weeks and a focus part is the runaway stabiliser. I'm sure we will get a chance to have a play and try to recreate the event.
One of the questions is whether the sim’s modelling is actually correct, or whether the tailplane/elevator relationships is actually from the pre NG models of the aircraft.. If the model is not correct, then everyone who thinks they can actually control the aircraft after one of these events is possibly mistaken. All TBA I guess.
 
One of the questions is whether the sim’s modelling is actually correct, or whether the tailplane/elevator relationships is actually from the pre NG models of the aircraft.. If the model is not correct, then everyone who thinks they can actually control the aircraft after one of these events is possibly mistaken. All TBA I guess.

Absolutely. I’ve been told checkies can try to emulate MCAS in the NG by leaving the flap out to simulate the faster trim rate.

There’s a sentence in the old 100/200 series FCTM that never made it to the NG. Something I had come across during my research since all this happened.

Basically, if the PF was to actually release the back pressure, let the PM manually trim, it would have been easier to do so even at high speed. It has to do with the position of the jackscrew in the tailplane being quite forward and putting load on it while trimming in the same direction.

I shall see if the theory works in a couple of weeks but I suspect I’d need A LOT of altitude to recover.
 
Apparently it’s a letter of intent, not a firm order yet, and if they are converted to firm orders they’ll be assigned to Vueling, Level, and BA flights from LGW

Yes loads of wriggle room to get out of it if the situation continues to deteriorate.

Quite smart actually, screw your under siege supplier down get an great price but have an easy out if the problem becomes too big / a toxic PR issue later.
 
I shall see if the theory works in a couple of weeks but I suspect I’d need A LOT of altitude to recover.

I’ve found mention of it in a number of places. It was apparently a taught procedure, and a number of the old and bold wondered how it disappeared when the NG appeared. An article a few weeks back had it being flown on an NG sim, and the scenario they used involved the use of about 8,000’ of sky.

There’s a catch 22 in all of this, with regards to large amounts of nose down trim. One reason that the trim wheel becomes so hard to move is the very high speed that was reached. The simple solution would be to just pull the power back....but if you do that you’ll add to the nose down moment, and so make the trim issue even worse.
 
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So it comes back to the last item on the runaway checklist - manually turn the trim wheel. Boeing says that is what you do in all the 737 - classics to Max.
Unlike all the other control surfaces on the 737 which I think have hydraulic assist, the manually operated trim wheel is unpowered. Presumably there is some degree of mechanical advantage engineered into it but without power I wonder if its like trying to steer a power steering car without power in the steering or worse.

Q: Has Boeing ever studied the torque necessary to manually turn the trim wheel and how that torque changes with airspeed?
 
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