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Old 21st Feb 2012, 19:15   #1381 (permalink)
 
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Let's not forget the PF did two things perfectly after the loss of the autoflight.

"I have the controls". Perfect.

He input Left ROLL, and NU. Had he not, the a/c would have continued its right bank and Nose down (3degrees). I give the ship ten seconds to be rolled 90 degrees, and flight Path Vertical. DOWN
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Old 21st Feb 2012, 19:29   #1382 (permalink)
 
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Grrr

Lyman opined:
Quote:
organfreak. "Dollars to doughnut......" Hmm. Right, that is not speculation, that is an accusation. We should be better than gratuitously making wagers on a dead man's training.
Excuse me sir, with all due deference, I know exactly what I meant when I said that. It most certainly is speculation. I accuse him of nothing, but I suspect that he didn't know, based on his driving. "Dollars to doughnuts" is simply a colorful expression, and far from a serious wager. Engaging PLONKing device; I've read enough. BYE now!
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Old 21st Feb 2012, 19:33   #1383 (permalink)
 
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Oh, and....speaking of "gratuitous," I'm speculating (again) that you are the only one here in the forum who doesn't believe the pitots were fouled by ice.
Wanna know what I think? (Probably not.) Preposterous!
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Old 21st Feb 2012, 19:47   #1384 (permalink)
 
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Quote:
Let's not forget the PF did two things perfectly after the loss of the autoflight.

"I have the controls". Perfect.
Lyman: One thing....

Quote:
I have the controls". Perfect.
Nothing from then on was perfect. Whatever he did to counter the right bank/nose down was certainly NOT executed anywhere near perfectly, with the end result being the same outcome as you postulate would have happened had he done nothing... just a number of seconds and wild ride later.

I have steered clear of commenting for a very long time, primarily because we have received nothing new to comment on. But you woke me up.

Back to silent mode.
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Old 21st Feb 2012, 20:50   #1385 (permalink)
 
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Quote:
I'm speculating (again) that you are the only one here in the forum who doesn't believe the pitots were fouled by ice.
Well to me it aint nearly as important to know what initiated this specific event as to what actions were taken or not taken to mitigate the result.

That's the difference between finding a causal factor of blame "if not for ..." rather than accident prevention which should have been "in spite of .... "

I still await a report on this towards preventing future similar accidents
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Old 21st Feb 2012, 21:15   #1386 (permalink)
 
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wise words

Quote:
lomapaseo
Well to me it aint nearly as important to know what initiated this specific event as to what actions were taken or not taken to mitigate the result.

That's the difference between finding a causal factor of blame "if not for ..." rather than accident prevention which should have been "in spite of .... "

I still await a report on this towards preventing future similar accidents
Thank you for that comment, it forced me out of silent mode for this moment.
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Old 21st Feb 2012, 22:16   #1387 (permalink)
 
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Quote:
PNF said, “we’ve lost the speeds then,” then, ”alternate law protections
Thanks, Organfreak, Lyman, memory did not serve.

I just looked at the law matrix again, and note limitation of AOB to 67 deg is active in Alt 1. IIRC, the degradation kicked AF 447 into Alt 2, so stopping the roll (besides being standard airmanship in response to an undesired roll) would be the natural response, but also necessary since it won't stop itself.
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Old 22nd Feb 2012, 00:21   #1388 (permalink)
 
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Pilot S/A, instant

LW

Likewise the Pitch was trending up, from 0 degrees (-3 from a cruise setting) so not only was arresting and reversing ROLL important, but from PF's 'snapshot' of PITCH, his NU was not required, in fact, he should have left PITCH alone, but to my mind he didn't have the time to orient his inputs. So what ensued was what MB calls a potential PIO, and a robust NU that resulted ultimately in their demise. Inheriting a maneuvering a/c in those conditions may not be appreciated by the cognoscenti here. I continue to insist that the critical time frame is the twenty or so seconds either side of a/p loss. Sure CRM seems non-existent, and a basic understanding of what the sirframe was up to as well, however, once upset, the odds were long. Captain says it all: "We are going to crash, this cannot be..." "Climb", "No, No, don't climb." "Pull". "But I've been Pulling for some time". A regular CF, but the horse bolted long before this abject confusion. I am glad BEA are concentrating on HF, however, this wreck was not such an unexpected event, given the traps set for it right along. This flight was flukey, and an embarrassment to all involved. Such a loss.
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Old 23rd Feb 2012, 01:10   #1389 (permalink)
 
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Our agenda

Hi,

Prevention, as i understand is what most of us should be pursuing through careful analysis and thinking.

In order to be able also to verify if the final report gone well and deep to the most important points among all the involved issues.

Our effort could allow us also to evaluate the conclusions, obviously if the report brings finally all required factual information.

In the meantime, as i understand we could increase our capabilities with the natural Synergy of an interacting group.

Always necessarily unbiased.

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Old 25th Feb 2012, 17:14   #1390 (permalink)
 
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Lightbulb what is that ?



Hi,
Quote:
Originally Posted by RR_NDB
In the meantime, as i understand we could increase our capabilities with the natural Synergy of an interacting group.
is it this thread ?

I have never learned so much outside of mine own life, that with PPRuNe
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Old 26th Feb 2012, 21:00   #1391 (permalink)
 
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Deserve, THEN Desire

Hi,

what is that ?

I desire to understand, if possible, everything on AF447.

To do so, to deserve i use all means available.

PPRuNe and the SYNERGY of an interacting group is a good resource!


Last edited by RR_NDB; 27th Feb 2012 at 01:45. Reason: Typo
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Old 28th Feb 2012, 15:27   #1392 (permalink)
 
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Difference between systems voting among 3 or 5

Quote:
Originally Posted by RR_NDB
It seems almost ridiculous the fact the aviation industry is still today using sub heated Pitot's.
Were they subheated ? Who had never a sudden pitot failure ?

AoA indicator is a mandatory solution after the AF447 loss of control, that has already been said by some of you.

But three systems (Airbus) may be replaced by five (Space shuttle), to have a better resolution of systems voting : With two pitots tubes blocked by ice the vote among three says these two are good ! And the third not blocked is supposed to be false... The vote among three is cheaper, the vote among five is much safer !
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Old 28th Feb 2012, 22:23   #1393 (permalink)
 
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tly

roulishollandais

Better still with two only Pitot Tubes ! These two, if designed differently, but to spec/reg, will never fail simultaneously, the fail chain cannot be identical. It does not eliminate failure, only failure in concurrent fashion.

Anomalous design.

Three of the identical design/manufacture are three blind mice, identical triplets.

Reasonably stupid.
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Old 29th Feb 2012, 00:45   #1394 (permalink)
 
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Amount of probes

Quote:
will never fail simultaneously
They didn't fail and certainly not simultaneously. if they clogged up for more than 10 sec. at the same time
the ADR DISAGREE message would have been displayed at ~ 02:10:15 ISO 02:12:xx.

First RH(FO) Pitot freezed up, 5 sec. later LH probe, a few sec. later STBY probe which returned to normal value for a brief moment.
@02:10:20 LH and STBY returned - but faulty -.
@02:10:40 LH was back on line (correct displayed) and 5 sec. later also RH probe. (FDs returned and needs 2 valid speeds)
At that time they switched over to ADR3 as source for RH PFD,

IMO If they didn't had done that action they would have had proper and coherent speed displays on both LH as RH PFD. (35 sec. after start of event)

ADR3 returned at 02:11:10.
ADR 1 returned in ~30 sec., ADR 2 in ~35 sec. and STBY in ~1 minute.

loss of speeds thereafter caused by hi AOA & NCD ADIRU output.

@RRR:
Don't know what you mean with 'sub'heated, its self temp. controlled.
The heat applied is inversely proportional to the temperature of the probe.
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Old 29th Feb 2012, 11:01   #1395 (permalink)
 
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Quote:
It does not eliminate failure,...
Right, so survival will always depend on correct application of the appropriate procedure. Would it be very difficult to have the pitch and power appropriate for the flight condition displayed on the ECAM? Would an "Ice particle detector" be useful?
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Old 29th Feb 2012, 14:36   #1396 (permalink)
 
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Hazelnuts39

Right. Full circle then. There have been dozens of theories, and points of view, not to mention politics. You bring us back to the fundamental focus of this crash. If it is to be instructive (at such a cost), we need to address some few things.

BUSS not important? Do posters here dismiss its possible ability to save the flight from the Sea? Add BUSS, and the a/c lands in Paris. Add PITCH/POWER, CRM, high altitude upset training (or at least emergent resources to instruct),(check lists to address it), the pitots are less important. Things break, but procedures are developed for that eventuality.

Particle ID? Perhaps a high speed version of a Particle separator? Design makes progress, but the impetus for change is lessened when players seek scapegoats.

We will see how far the authority goes to be aggressively honest, in the interests of the pilots and the passengers. If this is but a reprise of Rudder hardover, fuselage fracture/disintegration, and several iterations of a fundamental flaw must ultimately goad the players into change, it will be sad. Also, not unexpected.
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Old 29th Feb 2012, 15:06   #1397 (permalink)
 
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HI HN39,

I suppose you mean translating the UAS Pitch/Power table into a formatted ECAM message?

Then the parameters required are: FL, Flight mode (CLB, Cruise or Descent), GW and F/S config.

- FL comes from Air data (or GPS ALT have to be used)
- GW normally comes from FCMC (Fuel Control Monitoring Computer),
FE computation is used if both FCMC fail. so available.
- F/S Config wouldn't be any problem.

- how would it determine Flight mode?
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Old 29th Feb 2012, 15:10   #1398 (permalink)
 
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Talking I keep saying this; don't read

Everybody's got an opinion. I've got a bunch of them!

I hope that they fix every single possible thing that might have
contributed to the confusion and crash, no matter how tentative. Sure, that would cost lots of $$$, but the mass extinction of 228 lives is just unacceptable. The bottom-line-calculations of cost-benefit-analyses are, to me, an obscenity.

Flying has famously gotten more and more safe, in statistical terms. But for me, the sheer horror of this kind of death trumps everything else. It's still not safe enough for me.
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Old 29th Feb 2012, 15:45   #1399 (permalink)
 
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Quote:
Originally Posted by A33Zab
I suppose you mean translating the UAS Pitch/Power table into a formatted ECAM message?
No, I would think more like a back-up for the UAS 'memory item':

IF in TOGA: .... TOGA/15°
ELSE, below FL100: CLB/10°; above FL100: CLB/5°
THEN: Refer to QRH
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Old 29th Feb 2012, 15:47   #1400 (permalink)
 
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It costs a bit more to avoid (divert around) CBs. But it's SOOOO much safer. You don't get ice on your pitot tubes when in the clear. And you get home in one piece. Some people just don't seem to get it. Unbelievable!!!!!!!
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