Nope -They knew exactly who they were selling to- the MAX had to be' the same ' as the NG other than cheaper to fly, and a few new shiny objects. And NO extra sim time. SW who was a major customer said if sim time. cut us a check for 1 Million per plane.

The most egrious issue was allowing a single sensor to take control from the pilot. And no mention, no flags, and no change relating to that issue in the paperwork. All else flows- follows from that choice. AS to pilots- ' average' doesn't cut it - west half of the bell curve always applies.

It resets on pilot input to the trim switches. Those are pilot inputs.

It responds to trim switch inputs, from the pilots. Not only does it stop immediately, it resets. Had the pilots let the trim switches alone MCAS would have run once and stopped out of trim. Had they over trimmed ANU, then MCAS would have brought the trim back to nominal. Much like someone coming across a cute bear cub and going to cuddle it, they did not realize what they were provoking.

The discussion was for what MCAS was designed to do when the AoA system was working correctly.

MCAS should also be dependent on AoA - which it was doing in the accident aircraft. The amount of trim is dynamic pressure dependent so there's that, but it should gradually apply trim AND as the AoA increases and stop if the AoA stops increasing rather than running continuously for no reason. Again, under the conditions it was designed for. Since the AoA was not decreasing, MCAS ran until the timer ran out.

OldnGrounded

It was not a secret by the time the ET302 flight crashed. I knew how it was working with the failed AoA data and how it responded to the pilots from the preliminary report that was issued in, what, December? Months before ET302. I think that knowing a little about it was what made things worse for ET302 as the pilots seemed to pick some details and actions out-of-order and in the worst possible way, as if they recalled reading something about it once but were foggy on the details.

A critical piece I've never seen is the force required to hold the nose up through the progress of the accident flights and at what point the forces should have been high enough to demand attention to pitch trim.

Care to explain how that works, please?

Perfectly in every 737 except the MAX.

A secret even when the ET flight crashed - pulling back hard on the elevators use to work fine.

The quote requiring explanation was That was the specific bit that seemed to require explanation.

Many months ago it was highlighted that the 737 had a smaller elevator in relation to the stabiliser than other Boeing aircraft. The longer this goes on the more relevant it appears.

The ground was close- pushing forward would be not a thing to do, when you wish to climb G or no G every visual indicator was pull up.

Also given MCAS was a turbo trim speed - more reason to pull back on the yoke than use the slow trim switch to gain height.

I honestly doubt the crews noticed much in the way of any G forces, but that is just a guess.

Finally Another Test Flight
 

After no apparent test flights for almost three weeks, there was finally another flight yesterday,. Hopefully Friday the 13th will bring some luck to Boeing.

If you haven't looked at the flight tracking for these test flights as of yet, you are missing something fascinating. Go to flightaware.com and for the flight, type in BOE1. Then scroll down to see the flights by date.

So no negative G then, you agree, which was my point. All your other explanations and comments are not necessary, thanks.

No I do not agree nor do I think it is relevant.

I prefer not to be narrow minded, so happy to hear your relevance of the G.

FWI, my limited experience with G's and flying.

Is that the fun beat ups dog fighting over the beach to impress some campers in a Pitts and a Yak proved to have much higher G recorded on the meter than a aerobatic display. The dog fight seemed less G than the hard display on my body - but the G meter showed much different.

P.S I am not a pilot but have worked in the industry in several countries at many levels since 1985 also a aircraft owner

That's an interesting flight compared to the last few after 3 weeks on ground. 35kft dives and stalls followed by similar at 15kft. It may, of course, have nothing to do with the current grounding.

I'm guessing that Grebe was visualizing the flight deck of an airplane screaming Earthward at V[max|never\whatever]. Pretty likely that the crew would be (was!) experiencing negative gravitational forces.

It is a known phenomenon that some people react to negative G with a large and sustained PUSH on the stick to a crazy attitude (+forward trim if applicable), even if there are massive visual cues that it is excessive. For example, it has resulted in fatal glider accidents after a winch cable break (first action, adopt a normal gliding attitude = brief period of negative G), where the pilot has pushed, and continued to push extreme nose down, right into the runway clearly visible outside the canopy.
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Groooannnn- suspect some missed my sarcasm for starters - but perhaps a bit more explanation by this SLF as to the negative g comment- For the real pilots here - please excuse me -its just attempt to clarify what I think someone missed is the frame of reference- being the pilots-crew- passenger frame .

1) As I recall, the flight recorder traces on one of the flights did show negative g due to flight path altitude change ??
2) My frame of reference was to the pilots body, positive g being what you get when you are normally pushed down towards your butt, and negative being when your motion is towards your brain or top of head while sitting.
3) If one assumes you start in level flight i/n smooth air- then 1 g positive. IF you or HAL pushes stick forward or moves elevator - stabilizer such that you rapidly start to dive, the flight path ** starts** to be circular in the vertical plane. And assuming you stayed in the ' outside' loop, pilot-passengers would be experiencing negative G- ( motion towards your head ) throughout. Just how much would depend mostly on velocity. And unless you are strapped in, you will float up !
4) Several examples come to mind - Vomit comet with a 707, etc in a parabolic flight path
A ' circular ' orbit around the earth since you- station- are ' falling' towards the center of earth, etc in a mostly circular flight path.



Nuff...

Sick, #4508 ‘It is a known phenomenon that some people react to negative G with a large and sustained PUSH on the stick to a crazy attitude (+forward trim if applicable), ’

See Flydubai accident - not so much negative ‘g’ as a reduction - less than 1.

Any technical references or formal definition for this phenomenon ?

If it had worked correctly, we wouldn't be having this discussion.

Your reference to negative G forces* was perfectly logical and fits with what we know about the accident flight(s). I have no idea why some appear to think otherwise.

*As experienced, of course. We're really talking about relative acceleration, but neg-G is the usual terminology.

A CFI told me about it - he also personally had a student who was frozen, holding full forward stick after a simulated cable break and he had to scream at him, and pull at full strength to make him let go. I also recall reading about it in an accident report some years ago. Sorry, locating it on my phone here is not really practical, but a search might find. I had flyDubai in mind when I mentioned it, but then the subject of negative G came up here.