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AF 447 Thread No. 7

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AF 447 Thread No. 7

Old 12th Nov 2011, 13:04
  #121 (permalink)  
 
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I do not think the PF (and the PNF + Captain) made the same basic error as Old Carthusian has made.

What did they see?

**************

Having recovered the contents of the Avionics Bay, and the boxes, will BEA report as to what the Pilots were privy to in the way of displays?

Because from the outset, and to this day, one has difficulty believing that all three pilots missed the Attitude cue, believed the Vario, and were satisfied not to push the nose down. In fact, at one point, Captain says "Climb!". Not likely a result of seeing 15NU on the panel, with a descent of 11-15 thousand fpm. The two are not compatible, and because every wag here wants to be an expert, claim the pilots have stink for think. All Three?

For that matter, what was the command pilot seeing as he took control? Did he have honest data? I have my doubts. Would a simple Back up AH have been a life saver?

The communications twixt 1 and 2 show a distinct lack of common thought. If PF's reads were total duff, why wouldn't he hand off ?

He would, and that is why I think he felt his input was reasonable.

His reads were unreliable. imo.

Last edited by Lyman; 12th Nov 2011 at 15:07.
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Old 12th Nov 2011, 13:09
  #122 (permalink)  
 
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Originally Posted by rudderrudderrat View Post
Old Carthusian,
Isn't that exactly the same error that PF also made?
Likely so...
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Old 12th Nov 2011, 13:14
  #123 (permalink)  
 
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@rudderrudderrat: Yes, very likely!

@Old Carthusian:

Originally Posted by Old Carthusian View Post
Retired F4
Both the PF and PNF have displays with the same instrumentation on them. Your artificial horizon will tell you if the plane is climbing or banking. You derive your rate of climb (or descent) or descent from your altimeter.
Originally Posted by Old Carthusian View Post
BOAC
Of course artificial horizon will tell you if you are climbing - what do you think the gap between the horizon line and whatever symbol is used for the aircraft means? Yes it means your nose is raised but it also can be used to ascertain that the aircraft is climbing.
[My emboldening above]

With respect, repeating the same incorrect statement multiple times, does not ever make it correct Members BOAC, Retired F4, rudderrudderrat etc. are absolutely right in refuting your assertion on this point.

Please consider the other name for the artificial horizon is the attitude indicator. It is not called a climb/decend indicator - it only shows the plane's attitude (relative to the ground). The Wikipedia article on the AI seems a reasonable introduction, and I respectfully suggest that you read it - note that it correctly explains about showing the plane nose-up or nose-down (regarding pitch), and it correctly does not state that nose-up == climbing, since that would be a fallacy.

Attitude indicator - Wikipedia, the free encyclopedia

To summarise:

- When you are climbing, the AI does usually show nose-up attitude.
- When the AI shows nose-up attitude, you are not necessarily climbing.
- Therefore use VSI or altimeter (not the AI), to see if you are climbing/decending.

Does this help to explain the type of replies you've been getting?

[Edited to add "usually" regarding AI indication in climb - turbulance is another factor which alters this indication, and is yet another reason why the AI cannot be relied upon to show climb/decend indication!]

Last edited by Diagnostic; 12th Nov 2011 at 13:29.
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Old 12th Nov 2011, 13:32
  #124 (permalink)  
 
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If you had bothered to read all my posts properly you would note that I am perfectly aware of this. Selective quoting is all very well but I am guilty of abbreviating far too much and being too wooly in my terminology. However, given the phantoms that are being chased down here that can be forgiven. Actually I will strive to be a bit more precise in future - after all I can't very well criticise others if I am guilty of the same sin.
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Old 12th Nov 2011, 13:36
  #125 (permalink)  
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Good stuff, guys (and girls?), and really more suited to the wannabee forum, and I fear we are wasting our time with this 'shoal of red herring'. Personally I am relieved to see that the Old Carthusians appear to have no connection with aviation.
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Old 12th Nov 2011, 13:45
  #126 (permalink)  
 
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Wrong BOAC - I do have plenty of connection but the rebuke in this case is well taken. Next time - engage brain then type.
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Old 12th Nov 2011, 13:57
  #127 (permalink)  
 
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Originally Posted by Old Carthusian
If you had bothered to read all my posts properly you would note that I am perfectly aware of this.
How do you know what I "bothered" to do? That's a judgement call you're not qualified to make, unless you're looking over my shoulder at what I'm reading.

I have read all your posts in this thread ("properly" is subjective and also depends on the clarity of your postings), and it's definitely not clear that you are aware of the correct interpretation of an AI. I don't claim to be perfect, but I was just trying to help, after believing there was a genuine misunderstanding on your part.

Originally Posted by Old Carthusian
I am guilty of abbreviating far too much and being too wooly in my terminology.
Thanks for explaining how we got into this.

@BOAC - Agreed, I'm stopping here.
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Old 12th Nov 2011, 13:58
  #128 (permalink)  
 
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At this point, Old Carthusian, you would need to go in a flying school and ask a flight instructor to demonstrate you what the flight instruments and particularly the artificial horizon may or may not indicate regarding what the aircraft is doing.

Just to make sure, what is your experience in instrument flying ?
What is your experience in flying ?
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Old 12th Nov 2011, 16:25
  #129 (permalink)  
 
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You have no 'career' information in your profile, so I have to conclude you are inexperienced in Instrument flying.
Is this a "You show me yours & I'll show you mine..."?
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Old 12th Nov 2011, 16:47
  #130 (permalink)  
 
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Cool

Hi,

Lyman
Not likely a result of seeing 15NU on the panel, with a descent of 11-15 thousand fpm. The two are not compatible, and because every wag here wants to be an expert, claim the pilots have stink for think. All Three?
Collective hallucination?
You can not rule out this possibility
Read police reports about testimony regarding the UFO's
Lots conclude a collective hallucination
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Old 12th Nov 2011, 17:03
  #131 (permalink)  
 
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jcjeant. Yes, a possibility of collectively focused interpretation of confusing data. I think that is what existed between the two, prior to Captain's return. A hybrid, though disagreeable "rapprochement" between LHS and RHS.

But, after Captain pops back in, the focus is on him, "What do we do?".

His is the new hope for a solution, and unfortunately, he does not grok the panel(s), nor does he see (relax....) the SS. There is virtually no chance he saw, believed, and acted upon two divergent readings from two separate instruments. His was the 'stuckness' one feels when out of options, let alone decent data.

It takes a leap of uncommon collective hysteria to believe these were three stooges. They were not, they were baffled by a situation that had gotten so far ahead of them, there was not sufficient time to unwind it, and try options.

So, back to square one: 2:09:30. A Flight computer commanding a dive, airspeed reads that were duff from either ICE or Turbulence, and a crew who were not "following" the bird as it lost its way.......

In the absence of explanation for the autoflight command to dive (Zipper), a postulate. The a/c malfunctioned, and the pilots were handed back an a/c that was in UPSET, without awareness of the level of trouble they were in.

Nothing of any sort by way of casting aspersions. This is unaddressed by BEA. How long will this remain the case?
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Old 12th Nov 2011, 17:13
  #132 (permalink)  
 
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Originally Posted by OK465
As far as SS commanded proportional 'G' and the THS, what was the 'G' indication in the Flight Data block during the full nose down SS command prior to manual re-trim?
At that time we were well established in a 15000ft/min descent, stable, no bank, a G meter would have probably indicated 1G.

With the SS full forward, I would expect the elevators to be full leading edge up for a simulator full nose down command, and be displayed as such on the SD.
Then we both agree that both elevators should show a full down deflection.
If it was not the case, it would be a major MAJOR concern ...

One then would in general expect the nose of the simulator to follow this command. Why it didn't in the 330 and evidently did in the 320 is what's at issue.
My personal answer would be that the 12 deg NU THS position influence for the 330 simulation had much more impact than the full ND elevators position.
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Old 12th Nov 2011, 17:15
  #133 (permalink)  
 
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Originally Posted by OldCarthusian
Instruments are more reliable than human perceptions .
This statement is correct, but it means absolutely nothing in the context of this discussion. The original problem with AF447, as far as we know, was UAS. Unreliable Air Speed. That is an instrumentation/indication anomaly. An incorrect instrument. In this case, the less reliable human was forced to deal with a computerized system unable to function as designed. In my opinion, the human is the only intelligent link in the chain, but the only link influenced by perceptions. The instruments and computers are not influenced by perceptions, but they are also unable to function in the absence of proper data.

Overall, I think your statement indicates an lack of awareness of the situation the pilots faced. In the interest of preventing further UAS instigated deaths, why don't we focus on the reasons the human perceptions were incorrect? In fact, they were operating/flying a machine that uses computed info for both flight indications and flight control. We HAVE to focus on the human to machine interface instead of defending the machine at all costs. Anything less is a disservice to the dead.
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Old 12th Nov 2011, 17:19
  #134 (permalink)  
 
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Lyman,
I can well understand your last post and I do share it.
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Old 12th Nov 2011, 17:20
  #135 (permalink)  
 
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Originally Posted by Lyman View Post
So, back to square one: 2:09:30. A Flight computer commanding a dive
Again with the making stuff up. Where do you come up with this, and do you find misdirection that enjoyable?

And airtren, could you be more specific with the "manufacturer problems", because outside of the pitot tubes, I don't see any.

Silent running re-engaged...
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Old 12th Nov 2011, 17:51
  #136 (permalink)  
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Originally Posted by OK465
Is this a "You show me yours & I'll show you mine..."?
- actually no, but based on the apparent complete lack of understanding of aircraft performance and instrumentation. Don't tell me you cannot see it?

Incidentally, all are welcome to see 'mine' - just a simple click.
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Old 12th Nov 2011, 18:11
  #137 (permalink)  
 
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Able to raise the dead with a mere click, eh? Erm, misdirection? I like to think of it as focus. There are anomalies present (and ignored) since day one. Why not cease the misdirection toward the messenger, and address the problems? "Nothing to see here, merely a poor graphing result....."

Full of conclusions re: defense, yet an obvious sleight of mouse when confronted with exculpatory?

If one owns the "correct" conclusions, one is credible? If one merely proposes, or asks a question, "off the reservation," one is to be ignored?

Nice try, Lazarus.
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Old 12th Nov 2011, 18:11
  #138 (permalink)  
 
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Note from a total non-pilot!

Yep BOAC, it is apparent even to me, re who knows WTF they're talking about and who doesn't! (I've learned a tremendous amount about flying the big jets by simply following these threads, thanks to all.)

I think that, given the complete lack of solid truth about this accident, toady we have gotten closer to The Truth in both threads (whatever that may be).
Clearly, it is much more complicated than either incompetent pilots versus evil software. Those firmly on one side or the other are talking out their, uh, patooties.

[A side note, if anyone is interested. I'm getting mysterious private messages from unknown parties that question me about misrepresenting who I really am. I don't know what the problem is, but I've apparently touched some nerves out there. It's rather unsettling to get these creepy accusations. Maybe they mistake my intelligence for some sort of sekrit piloting knowledge. ]

Last edited by Jetdriver; 13th Nov 2011 at 02:44.
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Old 12th Nov 2011, 18:17
  #139 (permalink)  
 
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Organfreak. It is the constant annoying paranoid PMs that I receive that have caused me to molt. It comes with the terror-tory....

This subrosa attempt at moderating is unsettling, but harmless. It speaks to the fear some have of probing questions.

CONFiture. Thank you, Sir.
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Old 12th Nov 2011, 18:24
  #140 (permalink)  
 
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Thanks for the reassurance, Lyman. Good to know.
I should have also mentioned that I also received some private thanx from more than one real pilot, for defending their posts. That tells me that I'm not (entirely) talking through my hat. And now, back to our regularly-scheduled tomfoolery.
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