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AF 447 Thread No. 10

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AF 447 Thread No. 10

Old 23rd Aug 2012, 01:11
  #61 (permalink)  
 
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Wow

Originally Posted by DozyWannabe

Originally Posted by gums
[Editorial comment: Cockpit layout something for another thread, IMHO. My friend was the captain of the Cali disaster, and the stoopid FMS had duplicate designations for a fix. The two of them realized that somethig was awry when the coupled-autopilot turned the wrong way, but continued their descent after correcting their course. Can talk about that tragedy someplace else.]
As I understand it, it was the paper map that was in error, listing Rozo (the correct waypoint) as "R", when it should have been "ROZO". What the AA965 crew did was type in "R", which brough up a list of matching waypoints, then simply hit "EXEC" twice, which sent them to the Romeo beacon near Bogota. The correct sequence was "R-O-Z-O-[EXEC]".
You just proved your humanity, or lack thereof. Gums asked for this to be discussed elsewhere. Your obsessed desire to have something to say for every occasion has betrayed you. Sometimes it's just best to leave something alone.

Sorry Gums
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Old 23rd Aug 2012, 01:21
  #62 (permalink)  
 
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With all due respect, gums did not request that it not be discussed at all, and rather than open up a new thread on a topic that has been discussed many times before, I elected to summarize what I knew here as briefly as I could.

In this case the FMS did not have two waypoints programmed in with the same designator (as gums said), but caused a partial entry to bring up a list which was sorted in alphabetical order - a feature which crews of the time were not trained on. I explicitly stated that the initial error was in the map supplied to the crew, and not the responsibility of the crew themselves.

I've lost friends to accidents and worse, so I'd never knowingly be disrespectful of anyone who'd gone through the same, but in this case there was a factual error in the telling which needed to be explained.

Apologies if I caused any grief or offence.
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Old 23rd Aug 2012, 01:30
  #63 (permalink)  
 
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I flew the same type B757 into Panama City that night, no moon, and my FO was concerned about descending visually and said the highest obstacle from here is a sailboat mast. I flew into Cali a lot after that and they offered me that same south landing and I always declined. Not because it wasn't safe but in respect for the people that lost their lives by the pilots doing it. The R outer marker was the same at Cali and Bogota. They lost situational awareness and flew into the hills from the valley going to Cali. Yes it was their fault but the FMC made it so easy to make the mistake.
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Old 23rd Aug 2012, 01:34
  #64 (permalink)  
 
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bubbers44 - both they and you should never have been given charts marking the outer marker as "R". This was a misprint and the designation should have been "ROZO".
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Old 23rd Aug 2012, 01:45
  #65 (permalink)  
 
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Maybe now it is.
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Old 23rd Aug 2012, 02:35
  #66 (permalink)  
 
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Not exactly. "Skill" and "ability to cope with a crisis situation" are two very different traits.
Exactly ...
Chief pilot say:
"This was pilots with maximum skill in the AF447"
But he will (nor AF) never admit that the "ability to cope" with the AF447 was not present
AF maybe train their pilots to have "maximum skill" but seem's they are not trained (or selected) to gain "ability to cope"
Maybe AF count on the 'luck factor" ?
Unfortunately luck is not always there when you need it in
Luck is something that deserves
Amundsen
Victory awaits him,who as everythings in order.
Luck we call it.
Defeats is definitely due for him,who has neglected to take the necessary precautions.

Bad luck we call it.
Three pilots who have no luck gathered by chance in the cockpit of AF447 ?
AF probably (maybe) thought it was not possible ... it is sometimes forgotten that there are some lotto whinners ....

Last edited by jcjeant; 23rd Aug 2012 at 02:52.
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Old 23rd Aug 2012, 03:13
  #67 (permalink)  
 
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Thank you, Bubs and Tex.

I shall never forgive my buddy for continuing the descent once they realized that the abbreviated FMS entry turned the AP the wrong way, and I have been amazed that anyone survived the "skip hit" on that mountain ( unlike the recent Suhkoi tragedy). Nick's final words are worth reading, and makes me cry. I lost other friends that had no clue about the rising terrain or the deficiency in the Viper auto pilot/FBW laws , 'nuff said on this.....

@ JCJ: "luck" is when preparation meets opportunity.

For many of us, it's "there but for the grace of God were I".
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Old 23rd Aug 2012, 03:55
  #68 (permalink)  
 
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Originally Posted by PJ2
The unilateral actions by the PF, within a second of the start of the UAS event do not conform to standard responses to abnormalities, nor did the actions of the PM as the problem rapidly degraded.
What do you want him to do when the bank is at 8 deg the attitude is 3 deg under a normal cruise attitude the altitude is 400 feet below the assigned FL and all of it under AP control ?

At the first warning, which is for AP disc, the guy grab the stick and follow the up FD command which is still visible for 3 seconds after that disconnection.

Never in that short period he can analyze that the problem is an unreliable airspeed indication. For the 30 previous known events, how many have called "UNRELIABLE SPEED" and applied the memory items ?

The initial action is necessary, what came after was not, the PF did not focus on the attitude and let the attitude to rise to 11 deg at a cruising altitude 10 seconds after AP.
The PM gave valuable indications but did not sufficiently prioritize the monitoring of the PF performance ... ECAM was calling him ...
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Old 23rd Aug 2012, 04:03
  #69 (permalink)  
 
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What if direct law ... 2 ?

Originally Posted by HN39
What were the PF's targets, and why would they have been different in direct law? Would direct law have prevented these targets to be achieved? Would there have been less "mayonnaise stirring"? Would direct law have prevented full sidestick deflection?
What direct law does ?
Itís here but I can try to tell more :

As soon as the real speed bleeds, the nose wants to lower, it is a natural protection net.
If nevertheless the pilot wants to pull in order to achieve his targets, the aerodynamic let him know what kind of effort it takes on the sidestick. If mayonnaise there is, every down command will materialize in down elevator deflection.

To stall an aircraft in direct law just takes more effort than in a 1G command and the BEA does not disagree on that.

But letís pretend the guy goes for full deflection before and during the stall ... and the PNF does not question anything of it Ö

THS is still at 3 deg and the stall cannot be that developed so the indicated airspeed wonít go below the threshold to silence the stall warning that will still warn when the captain is back. Of course if that captain had the chance to naturally contemplate what kind of input is made by the PF on the flight control commands Ö that could enormously help him to positively evaluate whatís going on here.

What many here like to call 'graceful degradation' had nothing of graceful during that night.
That law that trim and that sidestick concept worked against that crew that night.
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Old 23rd Aug 2012, 07:59
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Originally Posted by CONF iture
To stall an aircraft in direct law just takes more effort than in a 1G command and the BEA does not disagree on that.
It took about 5 - 6 degrees of NU elevator to stall the airplane. In direct law that would correspond to about 3 degrees (2.8 lbf) of sidestick, vs about 2 degrees (2.1 lbf) in alternate law. Do you really believe the PF would have felt the difference in his erratic movements of the sidestick?

Last edited by HazelNuts39; 23rd Aug 2012 at 10:41. Reason: stickforces added
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Old 23rd Aug 2012, 15:04
  #71 (permalink)  
 
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Doze, "skill" among pilots includes the set of "monkey skills" and set of "brain housing group and headwork" skills. Those two subsets are combined to create the larger set of "pilot skills."

I thus find the AF chief pilot's statement of dubious value. (If it has been translated properly).

I don't care how coordinated you are -- if your headwork is poor, brain doesn't work well while flying and you won't be much good at flying since you'll eventually run into something you should not.

Likewise, there are very well equipped (mentally) folks whose eye-hand-foot coordination renders them dangerous. We used to refer to them as "plumbers" back when I was a flight instructor.

Those skill groups come as a set, like the Lone Ranger and Tonto, or like Dolly Parton's left and right breasts.

You don't break up a set.

Last edited by Lonewolf_50; 23rd Aug 2012 at 15:05.
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Old 23rd Aug 2012, 15:23
  #72 (permalink)  
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Originally Posted by CONF iture Post #69
What do you want him to do when the bank is at 8 deg the attitude is 3 deg under a normal cruise attitude the altitude is 400 feet below the assigned FL and all of it under AP control ?
I'm not arguing that the initial response to the aircraft's (minor) bank (which he rapidly controlled), and the suddenly-lower indicated altitude. I am commenting on SOPs and CRM - I am observing what followed in terms of a crew response which was entirely non-standard, and upon this point we appear to agree. This is an observation, it is neither a judgement nor is it a statement of blame. Those kinds of statements are for others who are not doing flight safety work.
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Old 23rd Aug 2012, 16:22
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Very nice summary, Wolf-man.

I used to call them "mechanics", but "plumber" works as well.

My friends and I that survived twenty + years flying fighters had the combination of mental abilities, being able to think ahead of the jet, and decent hand-eye coordination. The mental component always seemed to me to be slightly more important than the Chuck Yeager "hands". But being able to fly the plane without thinking allowed folks like me to use what little smarts I had to survive and not become a smoking hole in the desert, or jungle, or a half mile short of the runway.

I soloed many troops that had marginal "hands", but they could think ahead and even if they couldn't hold speed within a knot or descent rate within 50 feet per minute, they were "safe" and effective and survived. 'nuff philosophy for now. But.....

"luck" is when preparation meets opportunity. I didn't see that on the part of the AF crew that dark night.
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Old 23rd Aug 2012, 16:32
  #74 (permalink)  
 
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ACARS Pitot Fault message

Originally Posted by PJ2
roullishollandais;

The way this system works is, these ACARS messages are not printed out on board the aircraft at the time they occur. They are transmitted to the airline's maintenance department in real time (timings as per early discussions on these messages), but are held in memory on the aircraft until the aircraft is parked at the gate, at which time a post-flight print-out occurs, which could and likely would include such ACARS messages. I have seen this many times
Thank you for your answer PJ2. I have seen the maintenance messages printed, and we can perfectly understand why the Captain wants to know that the next flight may be delayed due to maintenance . Another airline, another Captain. Would an AF Captain know the use of that ACARS printer ?
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Old 23rd Aug 2012, 17:14
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Originally Posted by gums
I used to call them "mechanics", but "plumber" works as well.

My friends and I that survived twenty + years flying fighters had the combination of mental abilities, being able to think ahead of the jet, and decent hand-eye coordination. The mental component always seemed to me to be slightly more important than the Chuck Yeager "hands". But being able to fly the plane without thinking allowed folks like me to use what little smarts I had to survive and not become a smoking hole in the desert, or jungle, or a half mile short of the runway.

I soloed many troops that had marginal "hands", but they could think ahead and even if they couldn't hold speed within a knot or descent rate within 50 feet per minute, they were "safe" and effective and survived. 'nuff philosophy for now. But.....

"luck" is when preparation meets opportunity. I didn't see that on the part of the AF crew that dark night.
The interesting thing is: Airbus fans think that the Airbus does allow them to "fly the plane without thinking" and I think that the Airbus requires me to think about flying instead of "flying without thinking". Perhaps more interesting is the fact that the previous pitot clogging incidents resulting in a positive outcome appear to have been "handled" by my kind of "fly without thinking" crews, while the accident crew appears (to me) to be the kind of pilots that think the Airbus allows them to fly without thinking. IOW's, both sides understand the need to "fly without thinking", but we have diametrically opposed views about the Airbus' contribution to that end.

I don't blame an Airbus style of flying pilot for feeling the way he does, I blame the business, training and regulatory environments that lied to him and told him that the Airbus "flys like any other airplane". See Operational Golden Rule #1.

Nothing I've ever previously flown (numerous commuter and transport category turboprops, various models of LearJets, DC9 and stretch DC9) required me, the pilot, to think about which mode the controls were in in order to properly fly the airplane.

Even with that said, I expect to spend the next fifteen years in an Airbus, then retire. I don't fear it, nor have disdain for it - nor do I trust it. I just wish that the books included a few simple statements. For example, "excepting a state when USE MAN PITCH TRIM in announced on the PFD, the SS is the sole allowable input for pitch. In degraded control states, significantly exaggerated pitch inputs may be required to effect the desired change" .
I've observed too many crews (from the jumpseat) and my own First Officers utilize the "slap the stick" method of control. The manuals should clearly indicate that this is undesirable, instead of the current FCTM language that states, "the PF needs to perform minor corrections to the sidestick, if the aircraft deviates from its intended flight path".

Personal experience shows me that smooth pressure applied to the stick results in adequate control. It also keeps my muscle memory trained to control the aircraft in a way that will be effective in aircraft with either (FBW or not) philosophy of aircraft control. The pilot who is trained to make minor corrections AS PER THE FCTM, is IMHO, poorly prepared to deal with situations that require true aircraft control inputs.
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Old 23rd Aug 2012, 20:13
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Instead of asking again for any Bus pilot to address "slapping" the stick, let me ask you, Tex.....

You say: "I've observed too many crews (from the jumpseat) and my own First Officers utilize the "slap the stick" method of control. The manuals should clearly indicate that this is undesirable, instead of the current FCTM language that states, "the PF needs to perform minor corrections to the sidestick, if the aircraft deviates from its intended flight path". "

I have called it "Quick Stick". 'Mayonnaise' is unsatisfactory, for it implies the action is not based on flying the aircraft....

"Slapping the Stick" works, so, is it similar to what I take it to be? I think it is a method of utilizing the controls such that the Angle of Incidence of the a/c is not affected by the THS. IOW, defeating the Autotrim.

We have seen video of it, I think, was it grity? It strikes me that if this is done to thwart the philosophy of Airbus, there may be a serious problem?

Muchas gracias amigo. Or as they say in Ft. Lauderdale: "Ah Swannee"
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Old 23rd Aug 2012, 20:17
  #77 (permalink)  
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Would an AF Captain know the use of that ACARS printer ?
I can't say if AF captains know how to do this as I don't know any AF captains but as an A330 captain myself, (retired), on our A330's the printout was automatic after setting the park brake and if there were any maintenance messages printed out along with the entire flight summary (times, fuel, etc) we placed them between the thrust levers for either Mtc's awareness, (they would certainly know how to print these messages), and/or the next crew's awareness. Generally the knowledge is not required of flight crews because there are other means to communicate maintenance issues to the next flight crew, (usually the log book, of which an examination is required by the crew before flight).

That said, if the crew wished to know what the ACARS messages were while in flight, that is easy enough to do by navigating to the appropriate ACARS page summarizing these messages and printing that page. I've forgotten the details but it can be done though it isn't an automatic feature in the circumstances AF447 experienced, nor would there be sufficient time to examine the messages. Also, the "Stall" warning from the FWC is not part of the ACARS message system and would not be in any of the ACARS messages.
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Old 23rd Aug 2012, 20:51
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Thank you PJ2.
The Pitot fault message was on the ACARS at 02:10... and was missing on the ECAM!
Of course stall is not a ACARS message. But if one of the three pilots had seen that Pitot ACARS message it would have help the crew... to analyse the situation and they would have known immediatly they had to go to the UAS procedure.
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Old 23rd Aug 2012, 21:04
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Cool

Hi,

TTex600
've observed too many crews (from the jumpseat) and my own First Officers utilize the "slap the stick" method of control. The manuals should clearly indicate that this is undesirable, instead of the current FCTM language that states, "the PF needs to perform minor corrections to the sidestick, if the aircraft deviates from its intended flight path".
From the jumpseat ....
Interesting real life recount .. so do you suggest that the AF447 captain was able (like you) to see what were making the two other pilots with the SS ? (and was certainly able to see the position of the trim wheels dial)

Last edited by jcjeant; 23rd Aug 2012 at 21:15.
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Old 23rd Aug 2012, 22:17
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jc, considering where the AF447 Capt reentered the picture, I doubt that he was looking at SS movement. However, I think it possible had he thought it necessary. I'd guess that he was overwhelmed trying to make sense of ECAM and flight instruments.

Lyman, I think it's just bad technique. I doubt that those who use said technique actually have a real clue about Airbus philosophy, no less have any desire to thwart it. They use it because it basically works in normal situations. A quick hit is all it takes. I prefer softer, more steady pressure; a technique which works as well.
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