An interesting read from the BBC
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From the press reports i read that the nose down trim was to be applied using hand held wheel ( for the lack of a correct word ) beside the pilots seats and they were too feeble and did not workā¦
anyways i suppose the folks investigating this would have by now got to the bottom of it and will be looking at how to fix it.
But the main problem is the instability of the airframe itself when the larger fuel efficient engines are located more forward on the wing to accommodate the larger engine.
This basic character needs to be sorted firstā¦
Some fighter planes are designed to be inherently unstable but this is not a fighter planeā¦ the airframe needs inherent stability not instabilityā¦
IMOā¦
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The Airbus A320 NEO - fitted with P&W engines
we see news reports of engine related trouble mid air quite frequently
So even Airbus has issues though not with the plane itself but with new fuel efficient engine choices.
for me - i would choose utter reliability over fuel efficiency in these matters.
Upside of fuel efficiency can be ripped apart by inconsistent performance and flight delays caused due to return to base.
regards
many many moons ago - i used to own a Royal Enfield bullet motorcycle,
It was carburettor tunedā¦
the mechanic would decrease the air to fuel ration by detuning and sometimes the engine would sputter and stop on the road.
reminds me of that.
regards
From what I understand it was not possible to disable just the MCAS. You had to switch off the whole trim system and use the mechanically connected controls but when the planes was in a highspeed dive the airpressure made this control require very high physical force to even move slightly.
Now the FAA are saying they are going to test every single plane coming off assembly which will cause long delays.
Boeing just had another failure when (unmanned) testing of the starliner project supposed to shuttling people to the international space station. For some reason the shuttle clock was 11-hours off (local time for the developers?) and instead of docking the ISS the shuttle started executing whatever was scheduled at 11-hours off. The meant the shuttle was tilted in such a way they could not get radio control over it for many hours and burned alot of fuel.
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We seem to have forgotten the Dreamliner that caught fire 
at Heathrow, faulty batteries. If that had happened in the airā¦
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In all these cases I see one common factor.
A lack of or deficient or incompetent oversight mechanism .
Or someone who signed off was not aware or had a faulty team around him / her.
To be fair, some accidents/design errors are down to simple human error - history shows this, albeit via the accident investigation regimes of various events.
This said, we mustnāt overlook the tragic circumstances which have taken place and itās correct all necessary learnings are taken from such incidents.
Take care most humans are caused by accidents.
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Letās go back 30 years to 1988 ā¦
"Official reports concluded that the pilots flew too low, too slow, failed to see the forest and accidentally flew into it. The captain, Michel Asseline, disputed the report and claimed an error in the fly-by-wire computer prevented him from applying thrust and pulling up. In the aftermath of the crash, there were allegations that investigators had tampered with evidence, specifically the aircraftās flight recorders (āblack boxesā).
This was the first fatal crash of an A320."
Airbus/Air France were also slow to identify and implement a retrofit of the Pitot tubes on aircraft, which together with their Joystick configuration that has independent feel between Captain and Co-pilot, didnāt help in the fatal crash of an Airbus A330, Flight AF447 in the South Atlantic.
Basically, new, human adventures donāt come with a guarantee of safety and never have done. But equally, they also seem to attract dishonesty in its worst possible forms.
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Boeing currently also has problems with premature cracking pickle forks on the B737-NG variant. These components dissipate load in the wing/fuselage joint.
Some posts have blamed the regulatory process. That seems incorrectly targeted, as the fault lies squarely with the manufacturer - yes the regulation system should have caught it, and clearly there are lessons to be learned and, it would seem, much tightening up to do, but that is the backstop, not the cause of the problem. Although not quite the same, its a bit like blaming the police for your house being burgled, rather than blaming the burglar, or Environmental Health officers failing to prevent an contamination of food with e.coli 0157 causing deaths, when the responsibility is the food producers.
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Thatās exactly why I said primarily Boeing and secondarily the FAA.
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That Boeing was allowed to virtually self-certify, by the very regulator that is supposed to have oversight (the FAA), is very telling, especially given the glaringly obvious shortcomings in the design of this variant of the 737. Design and implementation of a critical system that operates using data from only one sensor makes Boeing look bad, if nothing else; omission of this by the FAA is absolutely unforgivable. Myself? I would never fly on the 737 Max, because in my opinion it is inherently unstable in flight and therefore unsafe. Over the last fifty years or so, there is only one other aircraft that I have refused to fly on, and that was the DC-10. The Max is added to that list.
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The āmodificationsā that were introduced to the 737 to create the Max version were extensive, but primarily icreased the the Thrust/Drag couple remarkably.
The handling characteristics would therefore change, with a tendency for remarkable nose-up pitch changes when increasing thrust, and nose-down changes when reducing thrust.
To mask this change in handling, I imagine the pitch controls and servos were modified but even that introduced further problems. The MCAS (Maneuvering Characteristics Augmentation System) strikes me as an afterthought, added to make the Max āfeelā like previous versions of the 737. But even then, there appears to have been the risk of strong nose pitch-up tendency with high thrust settings such as when taking off or going around.
Nose-up pitching eventually leads to a wing stall and needs to be avoided (we teach all students how to recognise this, avoid it and recover from it - basically you push the control column forward !). A wing stalls at a given Angle of Attack (angle between the relative airflow and the wing chord). Given that the Max was fitted with two AoA measurement devices, I am surprised that Boeing chose only to rely on one device to input data to the MCAS system !
I am further surprised that they devised the MCAS system to push the stick forward in such a way that it was virtually impossible to stop pushing it forward regardless of subsequent events.
How such a novice system could get past conceptual design reviews without too much questioning is beyond me, never mind get through test-flying and certification by the FAA, EASA and other national certification agencies.
Basically, if Boeing said it was āOKā, then the FAA said it was āOKā, and if the FAA said it was OK then so did EASA and every other certification organisation.
The whole global system is up for review ! or should be IMHO.
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My thoughts exactly! There can be no doubt - all this points to regulatory failure.
There can be no doubt that Boeing have much to answer for in all of this, because the business/corporate culture has changed away from technical excellence and dependability towards shareholder value. This type of capitalism has shifted the culture to a place where risks are calculated and compared with benefits. This cynical calculation means that actually developing safe and dependable aeroplanes becomes a game, a calculation, rather than an assessment of moral integrity and accountability.
Take supply chain management (SCM), for example. Gone are the days when everything (or at least most things) were made in-house. Often, work was outsourced to places where labour is cheap. The downside, though, is that the savings are often lost because the costs of actually managing these (often) byzantine chains with (again, often) kafkaesque technical and management system standards are quite high, and itās almost impossible to effectively assure the quality of the product created. Put bluntly, itās a bloody nightmare and itās little wonder I decided to get out when I could!
The FAA should have been aware of these kinds of forces acting upon the industry, and should have had some kind of strategy for dealing with them. They themselves should have acted sooner, but they seem totally inept to the kind of changes within the very industry they were tasked to regulate.
So Iām sorry but this IS a regulatory failure. Ultimately, the buck stops with the FAA and, for that matter EASA and other bodies that regulate air navigation and airworthiness and that matters, because they are not accountable to shareholders - they are accountable to the very taxpayers, citizens, that fund them. That is the vital difference.
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It is most telling that the hq is in ā¦ Chicago!
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Is there a name of someone who is credited with such a convoluted design? He deserves a Nobel prize.
But it can be used for steep landings, e.g. at London City Airport! I donāt get used to the shaking though.