There seems to be a lot of misconception about use of autothrottle.
The simple fact is, if you want to apply power manually when the autothrottle is in use, you simply disconnect it.
That is why Boeing provide a disconnect button on the side of each throttle which is pressed by the thumb as one applies manual power.
it is absolutely instinctive.
I don't see the problem.

So how come we know they existed?

Because there were 25 hours of data on the FDR, and investigators spotted the RadAlt glitches. The crews might not have noticed, never mind reported it.

PLEASE read the thread! The answer is there.

theamrad: The elevator would be maintaining ALT, V/S, a pitch attitude or the G/S and it should not be beyond the capacity of a competent crew to co-ordinate manual power adjustments with an A/P flown approach to preclude any 'pitch hunting' caused by over large variations in thrust. Though if A/P A/T approaches are the norm and manual power inputs the exception I could perhaps understand how unfamiliarity with required power inputs might lead to some rough handling, even absent turbulence or gusts. But then are we not in danger of producing pilots geared to flying the automation rather than the airplane with all the downside potential that creates when the automation for whatever reason fails to perform as expected?

I think that most semi-sensible, also the nonsense, theories have now been beaten to death several times over and it is time to wait for more info being released......the poor mods must need a rest from policing this thread :)

7777777777777777777777

Rananim,

May I politely suggest that you switch the brain on before pressing the keys on the keyboard.

The points I were making were facetious. Of course you don't need the items in my list, that was my point. I put a ridiculous one at the bottom (flashing the dome light if the aircraft sensed peril - bit of a half Hitchhikers Guide semi reference), but no, someone on Pprune thinks I'm being serious. Maybe a flashing peril-sensitive dome light was not ridiculous enough.

For your enlightenment, the NG is crude and simple. You will discover this when you get on to some more modern machinery, possibly the 777 or an Airbus. Incapable during non normal - you will also discover that on other aircraft when flying single engine you can do full flap landings, autolands, and fully automatic go-arounds. Nasty to fly = unstable in pitch (NG only, EG was great). It's only really obvious when you keep swapping types.

Just in case you still don't get it, I was saying that you can put as many beeps and warnings into all those automated systems as you like, but on this occasion it was the fault of the crew for not simply disconnecting and flying the plane.

Well that doesn't sound like let's look into all the factors that led a crew of 3 who accumulated many thousand hours, including an F4 pilot (does the F4 have autothrottles?) to end up short of 18R?

That sounds more like but on this occasion it was the fault of the crew for not simply disconnecting and flying the plane.

Let's call the board and save the taxpayer some bucks.

Please advise if my brain unexpectedly went into RETARD (FYI, I did get the subtlety) .

ant1,

Indeed - I then went on to mull over what we really would like to know. Exactly what happened in there to cause 2 or possibly 3 people to fail to realise that the a/c was not maintaining speed? We will have to wait for the CVR for that. It may well be that the "primary cause" of the accident is rooted in the behaviour in the flight deck during the approach - though there will be many secondary factors thrown in.

What ever the scale of automation or not, it´s up to the crews to check and manage the system. The whole idea of automatic flight is to give the pilots less of a work load and more time to concentrate on scaning the instruments. Now, if that goes to pot and the scaning goes out of the window...well, your guess is, as good as mine to where the blame might fall? Now, not undestanding how the automation works is another kettle of fish!!!

jackharr:

I see. Well, As far as I know the engines are not mounted in such way that they provide thrust that does not go through the center of mass. That means the thrust from the engines will produce torque which will try to rotate the aircraft. So what Safta probably experienced in the sim was immense back-trim in conjunction with the torque produced by the engines. Yoke fully forward was not enough to get the nose down. Maybe he (she?) could have recovered with not that much power... Anyway, I've learned that applying full power is the textbook way to recover from a stall. Hence, full power it is...

But this doesn't apply to you question as they've already lost control. A stall situation is the very definition of loosing control, isn't it?

RadAlt Problems Noted?
Quoting me in prior post:

"If a sensor, such as the radio altimeter, is giving you erroneous information, you have the option to disengage its circuit breaker."

Smilin' Ed:
"I don't think anyone ever noticed the RadAlt problems on this or any of the previous eight flights. If they did, I don't think they reported it."
--------

Have you and I been reading the same thread? The radalt going to -8 feet, as reported, will give GPWS "Too Low, Gear", which was reported somewhere on the approach. It also caused the AT retard. It may have cycled between correct and erroneous, causing multiple alerts and warnings; things such as "Too low, flaps." It would also display "-8" on the EADI, probably in a yellow meatball.

Had the crew pulled the Radalt circuit breaker after the first erroneous indication, the AT would not have pulled the throttles back again in the stall recovery.

GB

FORESIGHT is quite correct, it is VERY easy to disconnect the autothrottles and move them manually. EVEN if you forgot the disconnect button (which is easier than picking your nose), you could simply overpower the clutch mechanism and move them just fine.

RAINBOE...if that lear couldn't stop its climb using manual throttles, the pilot should lose his license.

Some pilots just need a huge amount of training and the discipline to keep things working right.

:ugh::rolleyes::rolleyes::rolleyes::}

737 AMM 22-11-00-146 (DFCS Functional Description)

Engage and Disengage Functions
24. The signal from the SMYD that shows a stall condition and activates the stick shaker must not be active.

So the answer to your question is yes; if the pilots had not yet pushed the control yoke forward, the autopilot is supposed to disengage when a stick shaker is activated by the SMYD.

100% Percent Please,
Sorry,I didnt realise you were being ironic.This thread moves quickly and I jumped the gun.Pilot error.
Smilin Ed,

No AoA indicator on 737 flightdeck.Two AoA sensors feed 2 SMYD computers and they use TE Flap position and TAI bias to determine what is known as the STALL ID(identification) AoA.If actual angle of attack>Stall ID AoA,the SMYD's activate the stick-shakers.The SMYD refines the STALL ID AoA by incorporating other parameters such as high engine thrust bias taking N1 input from the DEU's etc..

- have you ANY idea how long it would take to locate? Have you any idea how long one pilot (the Captain in this case) would be 'completely out of the loop' (ok - I know...), twisted around looking at a panel of 40 or so breakers? Have you noticed they probably did not notice it anyway?

It is an option for the 737NG to be displayed on the PFD. It's controlled (on or off) by your CDS OPC software.

AvEng - this is useful stuff! If only we had the AMM......................thanks for the info.