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-   -   AF447 wreckage found (https://www.pprune.org/tech-log/447730-af447-wreckage-found.html)

dlcmdrx 8th August 2011 17:08

It is actually really sad to see so much ab apologists. Ab philosophy is clearly that of reducing costs, pilots costs included, and if that has so much flaws seems it doesnt matter, there are still a lot of short sighted people believing everything the bea says and shouting pilot error anytime they can

Lyman 8th August 2011 17:13

If not understanding how thye a/c keeps trimming, this is Pilot error.

If a fundamentsl trap, this is aircrafts error. If Pilots know the trim is happening, and cannot feel it, where do they see it?

Loose rivets 8th August 2011 18:36

Many years ago I posted on full automation. I suggested pilots were already redundant and electronics would take over within the next 20 years. Public sensibilities? We could employ actors. Then I quipped, "Oh, we already do."

It was meant to cut. I again referred to Davis' 'Handling the Big Jets' - later edition. Hey, I haven't seen a quote from that yet. Is there a single first officer that doesn't carry it with him these days?

It was all meant to shout: If humans are on the flight-deck, they MUST be able to fly the aircraft. Really fly it. Oh, and be allowed to fly it.

Twenty years on and every incident, let alone accident, will be built into the logic of civil airliners' control systems. All that will remain is what to tell the passengers. Frankly, if they believe half the horse-feathers they're fed now, they'd believe anything. They don't matter. Conveying the aircraft to destination with perfect safety is all that matters.

The entire problem that faces the industry now is how to bridge the gap from the human nervous system controlling the kit, to a total black-box industry. That really is not an easy question to answer.

Today I read of a new alloy. A molecular seeding that will make aluminum/aluminium very, very much stronger. Plastic aircraft are a stop-gap, in the same way the hybrid human/electronics control interface is. It's just getting over these years.

As an electronics bod who was later forced to fly the Zero-Reader, I know how difficult this transition period is going to be. The Zero-Reader was a smoldering pile of valves/tubes and melting rubber insulation. How the heck did it find itself advising human captains of civil aircraft?

Reverserbucket 8th August 2011 18:59


I again referred to Davis' 'Handling the Big Jets' - later edition. Hey, I haven't seen a quote from that yet. Is there a single first officer that doesn't carry it with him these days?
Sadly, yes.

Gretchenfrage 8th August 2011 19:23


It was all meant to shout: If humans are on the flight-deck, they MUST be able to fly the aircraft. Really fly it. Oh, and be allowed to fly it.
Your words in gods ear!

The reality is that whenever the automatics are no longer capable of handling, due to invalid signals they need, they throw the aircraft back at the human.

- Perfect - It will be him screwing up finally.
Good for statistics and engineers.

Second reality is that even when the automatics switch off autopilot and autothrust, it can still intervene with pilot inputs, through automatic protections, and therefore limit his authority.

Why on earth? ?
It had detected itself incapable of handling the aircraft, but still messes with controls.

Isn't that a paradoxon?


I am not entirely against automation and technology to improve safety. But the implemented systems must work flawlessly.
Otherwise I don't need them.
So before introducing even more protections, please fix the technology that's already on board.

Concerning statistics, lots of contributors just love those, I am still missing a serious one about automation induced pilot errors. This would give a clearer picture than the one containing just plain pilot error. Not that it would excuse any such error, eliminating those should be just as noble a cause, but it would point back at the magic automatics that benefit from too big a confidence and a lack of genuine criticism, as it would mean responsibility (meaning doe) from you who I mean.

kwateow 8th August 2011 19:28

I ask myself
 
Over and over again I ask: did these 2 FOs do any better than an average, armchair, MS Flt Sim "pilot"?

We'll never know, but they were paid big bucks to do better.

DozyWannabe 8th August 2011 19:38


Originally Posted by dlcmdrx (Post 6627656)
It is actually really sad to see so much ab apologists. Ab philosophy is clearly that of reducing costs, pilots costs included, and if that has so much flaws seems it doesnt matter, there are still a lot of short sighted people believing everything the bea says and shouting pilot error anytime they can

That's a pretty serious accusation - where's your evidence?

Lyman 8th August 2011 20:00

Here, the poster has said, "We the computer have some ill readings, so you pilot must fly, out." But the computer stays close, and interferes....

For Gretchenfrage then a new word, '.Paradoxicon..' A smiley airbus?

hetfield 8th August 2011 20:04


Concerning statistics, lots of contributors just love those, I am still missing a serious one about automation induced pilot errors. This would give a clearer picture than the one containing just plain pilot error
Spot on Gretchenfrage.

About one week ago I opened a thread about this subject at this very place.
It was deleted within minutes for whatever reason.....

AF447, TAM 3054, XL 888T, etc. etc.

blind pew 8th August 2011 20:24

KWATEOW
and for three hundred grand plus one would have expected the captain to be on the flight deck during THE critical part of the enroute phase!

Safety Concerns 8th August 2011 20:25

somebody asked about statistics. well no accidents involving european airlines during 2010. safety levels the best they have ever been.

its time to look forward. automation has improved safety but isn't quite perfect yet.

JJFFC 8th August 2011 21:38

@JCJEANT : Right Seat vs Left Seat ; how do you manage ?
 
I apologize if my last post appeared to point out a pilot error again. It is not my point.

My point is that you have two co-pilots with equal rights giving dual inputs.

If the two pilots have to hand-flight because of a mechanical problem, then:

- Can the plane detect and decide who's of the pilot it has to obey yet it has problems and gave the control to the pilots ?
- Can the designers predict in which seat will be the good pilot vs the bad and therefore, allow this seat to take control of the plane and withdrow this possibility to the other seat ?

In AF447, if the PNF or the Captain had not a mean to prevent the PF from giving inputs, since this PF didn't obey his Captain, what should have they do?

Knock Down the PF ?

OK : but what if it has been the PF that was right ?

This has nothing to do with the stall warning or the SS, since the PF'brain was stuck at nosing up whatever would be the stall warning !.

IMO, in the actual state of the art, only a human action could have stop the PF, not the plane.

In particular, it is wrong to say that the Capt and the PNF didn't recognized a stall. Not only they did but they gave the good advices to the PF, only 21s after the PF took control !

And they keep on asking the PF to go down for minutes.

But when the PNF took control, the PF re-took it, several times and again in the last seconds.

Without a knock down he would'have stoped.nosing up.

Should the Capt. have had a billy ?

Casper 8th August 2011 21:49

KWATEOW
and for three hundred grand plus one would have expected the captain to be on the flight deck during THE critical part of the enroute phase!

Couldn't agree more, blind pew. Crossing the ITCZ is not the time to be in the sack.

HarryMann 8th August 2011 22:52


The Aircraft was hand flown from a stable configuration into a stall situation, albeit unwittingly complicated by the autotrim..... leaving the best aviation experience/resource in the non control role , or absent from the cockpit and not decisively involved throughout.

The problem was a skill, perceptual (including spatial disorientation) and CRM one on the pilot/company side, worsened by design faults with the aircraft ( pitots, autotrim, stall warning parameters useless in a mjaor attitude upset, no A of A display, digital readouts vs analogue readouts worsening performance in emergency environment, unobserved sidestick)
Mimpe, pretty well covers it.... :D

A33Zab 8th August 2011 23:42

@Gretchenfrage:
 

The reality is that whenever the automatics are no longer capable of handling, due to invalid signals they need, they throw the aircraft back at the human.
To prevent the system of using faulted sensor input but unfortunately the human input was faulted too.


Second reality is that even when the automatics switch off autopilot and autothrust, it can still intervene with pilot inputs, through automatic protections, and therefore limit his authority.

Why on earth? ?
It had detected itself incapable of handling the aircraft, but still messes with controls.
It didn't messed up......... it followed PF demand and didn't limit his orders.



I am not entirely against automation and technology to improve safety. But the implemented systems must work flawlessly.
As pax may expect from the crew in front.

misd-agin 9th August 2011 01:34

Casper - Couldn't agree more, blind pew. Crossing the ITCZ is not the time to be in the sack.

Casper,

Agreed. I pick my break so that I'm in the cockpit if I anticipate difficult conditions. I don't pick my break, the conditions dictate when I'll go on break.

bubbers44 9th August 2011 01:44

Pilots should never be flying an aircraft they can not hand fly. These two obviously couldn't. If you always fly on autopilot, as Airbus and a lot of airlines want, you lose hand flying skills. AF447 crashed because of lack of hand flying skills. Why can't we let pilots do some hand flying enroute to keep these skills up or rebuild them?

Pitch Up Authority 9th August 2011 01:59

It is simple
 
There are those that train to pass a check and there are those that go beyond that.

Knowing your power-settings and attitudes for unreliable airspeed is something the first group doesn't bother about.

Having said so, flying a jet manually at high altitude (reduced dynamic stability) and low excess power available is not easy.

Another issue is that very few airlines train their pilots well for cases of failed sensors and/or ADC.

takata 9th August 2011 02:00

Autothrust
 

Originally Posted by Man Flex
Also very telling is the autothrust disconnect, the realisation that climb thrust has been inadvertantly applied and then the subsequent reduction in thrust.
The PF didn't want to climb otherwise he would have remained in climb thrust.

What is very telling is that none of the facts do fit with your "proposition".
When autothrust disengage, it doesn't "inadvertantly" apply "CLB" thrust (that's an urban legend) as thrust is frozen at its last setting which is independant of thrust levers position (CLB at cruise). Actual thrust levers position is only providing for autothrust its possible range of operation: when placed on CLB, autothrust may adjust N1% between IDLE and CLB level.
When autothrust is disconnected, a warning is sounding and an ECAM will display "ENG THRUST LOCKED", which means that Thrust is frozen. This should be acknowledged by the pilot, stopping the alarm, by moving the levers to their current settings or anywhere wanted.

In AF447 case, it is exactly what happened and thrust was locked at N1% 84, which is low for such FL and weight (about 94% would be needed at Mach .80). In fact, few seconds prior to disconnection, pilots changed their selected Mach from 0.82 to 0.80 (turbulence penetration speed). Consequently, she was decelerating. Next, thrust levers were not unlocked before about 15 seconds after autothrust disconnection, while she first climbed, then still at 84%.
When levers were unlocked, PF manually applied 100% N1, for about another 15 seconds, before reducing thrust when PNF asked him to go down... but she was still climbing. Shortly after that, stall alarms sounded and he applied TOGA while pulling up, and... she stalled. (it is taken from DFDR tracks and report).

Mimpe 9th August 2011 02:33

if he had just picked an appropriate attitude and power setting ( im not commercially trained) ...I presume its a bit over

1. 85 percent power and
2. 4-5 degrees nose up
3. checking wings level and minimal change of altitude,avoiding overcontrolling and changes to thrust... and
4. immediate (read...IMMEDIATE) call to Captain

none of this would have happened?

I also wonder whether the small thunderstorm in front obscured the Really Big One immediately behind that they ended up fyling into (my view of the relevant satellite depictions and track taken).Can this happen with weather radar? It seems they were in weather they really had no need to be in...supercooled water and all that. A right divergent track of about 20 degrees looked a lot healthier.


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