Machinbird

theficklefinger
As one who has spent quite a lot of time flying at night over water and far from land, there isn't any VMC at night without a bright moon shining all the way down to the water.
It is rare to see lights at night on the surface far out from land and one or two does not help in orientation.

augustusjeremyreborn
Nope. The trim held the trump card.

GarageYears

JD-EE: Normally I find your comments/assessment rational, but in this case I feel you are way off. Hal did not trim the airplane, the pilot input CAUSED the trim, no other reason than hauling on the joystick. Pitch-up commands for the majority of the ride down to doom.

- GY

CONF iture

Not too sure about that one Tyro ...
Could be an indicated airspeed of 60kts or anything below, AoA probes won't be affected by gravity with an obvious negative vertical speed of 100kts or above.

henra, I don't think there is anything as Alpha Floor protection in case of A/THR failure.
No one would trim up beyond a STALL WRN, how is it possible the Airbus still auto trim after such warning ... !?
Things don't add up here.

Svarin, your comment regarding the wiring (WRG) ACARS message is interesting. You will need to tell us more.

gums

Salute all!

Good to see many of the stalwarts back here later in the day.

Garage! Until we see the traces of the FDR, we won't know if the THS was commanded up by the pilot or Hal. My reading of the manual indicates the THS will stay at last commanded position once system reversion occurs due to Hal's opinion of reliability/validity of several parameters. From then on, the pilot has to move that wheel. So doesn't look like it will continue to move nose up due to pilot stick inputs after Hal is in Alt 2 or Direct law.

Some points/thots:

- The sticks add inputs, so a forward 5 deg on one can be overcome by an aft 10 deg on the other stick. We need to see the FDR trace. Of course, there's the "I have it" button on each stick, and that is another thing I hope the FDR captures.

One pilot here commented about the Boeing approach. For this plane, I would like that implementation. On the other hand, how many times is an IP "helping" the newbie? Or an old salt is "following thru"? Our Viper family model had tandem seats, so I couldn't see student studly's hands or feel his inputs. The computers added the inputs just as the 'bus.

- Several old salts here seem to advocate that some of the reversion sequences and even the "laws" could be simplified. I shall throw my lot in with those folks.

- Warning and caution indications seem to be less than optimum with regards to the most essential pilot action at the time.

- I have a really hard time with the AoA presentation, or lack thereof. The plane seems to have a comfortable range from basic cruise and stall onset. But once things turn to worms with known air data faults that have occurred in the past, I would really like to see what those vanes were sensing. In my jet, the AoA WAS GOD!!! Didn't prevent a deep stall, but you had to work real hard to get to one.

- I would love to fly a 'bus on an approach to stall maneuver. Some jets I flew announced the condition in no uncertain terms - wing rock, shaking, burble, buffet, etc. Others were as smooth as silk with only a slight buffet or buzz ( delta like F-102A or Concorde).

So what kinda feedback does the jet provide that you are treading on dangerous ground?

Are the pilots trained to recognize stall onset without having all kinda warning and caution lights?

and the beat goes on.

Gums sends...

jcjeant

Hi,

This is a first answer ....

john_tullamarine

.. one presumes that that statement is now in question ?

One point bothers me. Putting aside the possibility that the crew was simply overwhelmed by multiple sensory inputs and just could not think straight (and I suspect that we all have been in such a situation from time to time in the box), how is it that the observation of

(a) a reasonably level or nose up attitude plus

(b) low IAS plus

(c) a shedload of ROD

doesn't immediately equal the mental deduction of stall ?

jcjeant

Hi,

Indeed ...

I do not think that at the next Paris Air Show Airbus representative will make the same declaration to try to sell his equipment ...

mm43

JT
That is the crux of the matter, and their situational awareness was such that what they saw/heard/felt made no sense.

JD-EE

deSitter, "How would the airplane behave if its fin came off in the zoom? Wouldn't it start Dutch rolling?"

To quote a great philosopher, or at least a prior posting here:

Ohhh, nooooo!
Not again!!

More seriously, can you imagine the sequence of messages if the tail is lost? What electrical lines are broken? What hydraulic lines are broken? How does the airplane not know it's lost it's tail? I should be able to make a modest maintenance note to that effect.

I also note that 16 degrees is a tad more than I envisioned when I tried to place the plane meeting ocean with some forward motion and great downwards motion. When the flat surface of the elevators slams into the water the tail is pushed up sharply. It breaks off at the weakest point aft of the cabin. That tilts the assembly up. But the VS nose is still planted on unbent aircraft. The leading edge and trailing edge literally pry the VS loose from the plane as it hits the water. It probably hit the water slightly to the side and aft of the elevator. When its joints broke it must have rather sprung up into the air quite dramatically.

{^_^}

Machinbird

J.T., My initial reaction after reading the BEA document was to exclaim:
"Put these guys flying the Airbus in a real airplane and make them explore the limits."
This airborne simulator that babies them is ruining them!"

But then I wondered what kind of indications the PF had on his panel to make him do such a silly thing. I concluded it was initially probably very different from the side the DFDR was reporting on.

It has been said elsewhere that experiences that do not kill me make me stronger. This is particularly true in aviation.

blind pew

The more I read the more I think there but the grace of god.........

One of the few memory drills I learnt in the 70s was for runaway stabilizer and we had in effect that during this accident. - serious s**t on it's own.

Middle of the night.
Turbulence.
Hypoxia
myriad of warnings - some completely false.

Lack of training.
no ins or gps speed indication.
known pitot problem

I now honestly believe that most of us wouldn't have made it.

I only once used the TURB button on the DC10 - the other crew members were so comatose that they both kept switching the autothrottle back on.

Having flown the route for 6 years and operated in the european country where severe turbulence was an often occurrence I empathize with the poor b*****ds.

But I ain't so in love with guys who sold two crew and incredibly complicated "life saving" aircraft systems to the world.

What happened to the old values of leaving an aircraft's trim to the pilot, followed by if you point the beast in the right direction and add the correct thrust it will go where you want it to!

RIP

JD-EE

Graybeard, "JD-EE: Normally I find your comments/assessment rational..."

That was immediately after reading the report and before reading anything here. The trim simply followed pilot input, even to the point of becoming silly it was so extreme.

Hal betrayed them by failing to recognize the abrupt decrease in the plane's air speed without any control inputs to have caused it. Rather than declaring a stall Hal should have declared something else, "I'm lost in a maze of twisty little lines instruction code and need you to take command probably to fly pitch and attitude for a short while."

The stall warning created a wrong but apparently predictable reaction in the person flying the plane. Grab sky and grab speed.

I understand that in a more rational world at altitude a genuine stall warning means get the nose down and gain speed then get altitude back. But that never happens so it's never trained for, except it did happen.

Between Hal's erroneous stall warning and the pilot's trained in responses there may well have been no way for the pilots to really figure out what was going o and recover - especially so in that nerve shredded cockpit.

edit: Incidentally, this is not a programmer's problem or error. This is a design inadequacy above their pay grade.

{^_^}

deSitter

There should be an engineer on board whose job is to know the aircraft systems in his bones, not to fly the airplane, or at least not primarily to fly the airplane.

-drl

Bienville

JD-EE say: Um... are you ok? The plane stalled. That's why the stall warning went off.

I take it you are not a pilot. At 37,000 feet over the ocean, he hardly needed to "grab sky." -- Unless there was a 38,000 tree in front of him. The proper reply was to drop the nose. THE PILOT failed to do so. Not 'Hal" but the THE PILOT.

1) It was a genuine stall, that's why the plane fell out the sky.
2) High Altitude stalls do happen and they are trained for. The pilots failed to execute the proper procedures.

It was three stall warnings and all of them were legit. THAT"S WHY THE PLANE CRASHED.

-------------------

Really, if you have nothing to offer but drama laced nonsense, spare wasting the time of people who actually know a bit about how those airplane thingies fly.

jcjeant

Hi,

IMHO it's sometingh wrong in the BEA communication ....

At 2 h 10 min 16, the PNF said "so, we’ve lost the speeds" then "alternate law […]".


At 2 h 10 min 51 , the stall warning was triggered again. The thrust levers were positioned
in the TO/GA detent and the PF maintained nose-up inputs. The recorded angle of attack, of
around 6 degrees at the triggering of the stall warning, continued to increase. The trimmable
horizontal stabilizer (THS) passed from 3 to 13 degrees nose-up in about 1 minute and
remained in the latter position until the end of the flight.
Around fifteen seconds later, the speed displayed on the ISIS increased sharply towards 185 kt;
it was then consistent with the other recorded speed. The PF continued to make nose-up
inputs. The airplane’s altitude reached its maximum of about 38,000 ft, its pitch attitude and
angle of attack being 16 degrees.
Note: The inconsistency between the speeds displayed on the left side and on the ISIS lasted a little less
than one minute.



At around 2 h 11 min 40 , the Captain re-entered the cockpit. During the following seconds,
all of the recorded speeds became invalid and the stall warning stopped.


At 2 h 12 min 02, the PF said "I don’t have any more indications", and the PNF said "we have
no valid indications". At that moment, the thrust levers were in the IDLE detent and the
engines’ N1’s were at 55%. Around fifteen seconds later, the PF made pitch-down inputs. In
the following moments, the angle of attack decreased, the speeds became valid again and the
stall warning sounded again.


Make the math ... and the result is not "little less than one minute"

blind pew

JD-EE
edit: Incidentally, this is not a programmer's problem or error. This is a design inadequacy above their pay grade

Couldn't agree more - as is often the case in aviation the office wallahs are there because they can't fly and who better to lead the design philosophy team-NOT.

Trident destroyed by BEA management.

They also ordered a bespoke instrument panel for the Tristar based on the Lancaster and Trident.

Fokker 100 navigation system without ins platforms was lethal when you most needed - in mountainous terrain as it dropped out.

DC10 system pared down to absolute minimum by accountants.

and EADs don't understand their own systems - look at the bird that went through the blast deflectors at toulouse -EADS pilot/engineer.

Bienville

jcjeant... no the math is ok. 2 h 10 min 51- 2 h 10 min 16 is less than a minute.

THEN they lost proper indications a second time... Now whether the crew noticed they were valid for some time in the middle we'll never known. I personally doubt they noticed from the sounds of it.

blind pew

beinville
you are wrong

I trained for minimum loss of altitude assuming that the stall warning would happen on the latter stages of approach - full power and maintain attitude or stop it increasing unless it was extreme.

Automatics
We used to fly military type visual approaches with the engines in idle down to 500ft.
Two F100s had stall warnings on final turn at Nice - both were initially thought to be false as we had been told we had 100% stall protection a la airbus - not true as with a certain FMS selection we could get into an open descent mode without stall protection.
The books were rewritten.

The stalling demonstrations that I carried out on the sim were generally the same as taught in little aeroplanes and not representative of real life.

I had several stall warnings in the earlier part of my career - generally in turbulence and in all but one case they were written up as false which turned out not to be the case.

I seem to understand that the initial stall warning was false?

Again the Stab trim - this was considered so important on a couple of airliners that I flew that it beeped on every rotation of the wheel and we could reach a CB to isolate it if it started to runaway.

rudderrudderrat

Hi All,

If the pilots mistakenly believed they were in windshear conditions, it might explain why the pitch attitude was around 17.5 degs for most of the time, and why full back stick was used to prevent height loss iaw QRH 1.26.

I've seen some crews in the sim simply rely on FBW stall protection (rather than piloting skill) to nibble in and out of the stall warning during wind shear exercises.

Bienville

Blind Pew, please explain how I am wrong. I hope you are not saying stalls do not happen at high altitude. If so, you might want to google that before you answer.