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-   -   AF 447 Search to resume (part2) (https://www.pprune.org/tech-log/449639-af-447-search-resume-part2.html)

takata 18th May 2011 14:50

Bear,

Originally Posted by Bearfoil
I am posting in a timely fashion 'with permission' that there is nothing new to report.

Nice cut.
Once the sentence "there is nothing to report at this stage" is cut into "there is nothing to report", you can make big headlines like F. Amedeo, or say anything you imagine to prove any point of you, as you did.
But, hey, I wasn't really expecting that you will behave better than him!

infrequentflyer789 18th May 2011 14:51


Originally Posted by jcjeant (Post 6458521)
It's a way to prepare the public to accept the fact that in their next official BEA report ... crew will be pointed as making errors.
At least it's a possible scenario I can't discard.

Well that has been on the cards since the beginning, witness the previous reports noting lack of diversion, the excellent weather research of Tim Vasquez, and massive discussion here on weather radar etc. There is no way the plane decided to fly into a cb by itself (one day we may have a plane piloted by an artifical intelligence that choses to do that from a masochisitic sense of "fun", but that is not what FBW is). That only leaves pilot decision (or lack of) to explain it.

If the final report contains some criticism of the crew, I suppose you will now be pointing back to these posts of yours and saying that your conspiracy theory is thereby proved ? :ugh:

SaturnV 18th May 2011 14:57

Murphywasright, as mm43 recently noted about the awful results, in retrospect, of the June 1 search by both plane and ship, I would hope the final BEA report addresses the failures of that search, the causes of such, and what seems to be the unfortunate reliance in subsequent days on those awful results.

bearfoil 18th May 2011 15:02

Who says Vasquez' work is gospel?? Again with the "They flew into doom". Vasquez has shown error of up to 30 miles. At the outset, AF immediately reported, "The flight has reported "turbulences forte", then it was"Lightning", then the pilots were "unlucky with the Radars" (sic) (Gourgeon himself !!).

That was within the first month. All along with the bs, propaganda, and self-serving 'sacrifice' of the reputations of others. This has been a managed event, up to and including the "rabbit" of the leak. Do you for God's sake understand how much these suits spend on PR?? With more money than sense, (or integrity) the talking heads under contract have been spinning this since ORARO. If I am wrong, I will admit to it. In the mean time, scepticism is the fuel that fires objectivity.

MurphyWasRight 18th May 2011 15:13

SatrunV

Murphywasright, as mm43 recently noted about the awful results, in retrospect, of the June 1 search by both plane and ship, I would hope the final BEA report addresses the failures of that search, the causes of such, and what seems to be the unfortunate reliance in subsequent days on those awful results.
Totally agree, sorry that I was not clear that I was commenting on the pinger/sonar scan search phases, not the original search for wreck or hoped for survivors.

RR_NDB 18th May 2011 15:14

Checking CSMU integrity (sealing) before powering up
 
Chris and GS


Quote from Golf-Sierra:
As far as checking if there was water in the module prior to powering it up - would not the simplest way be to weigh it?

Nice one. Perhaps the experts can comment?
If i designed the "pressure vessel" i put a VERY SIMPLE SENSOR inside:

A humidity detector. There are several (one is VERY CHEAP) to implement it.

Electrically (using Ohms law) you EXTERNALLY check the electric resistance of a "sensor" inside the CSMU cylinder.

There are risks associated in powering up an electronic circuit contaminated by salt water.

My kids destroyed the processor area of an air band radio after a drop in a pool. ITHO if they washed and dried it before powering up very probably we saved the portable VHF.

The idea to weight is another possibility but may not indicate the presence of salt water moisture.

MurphyWasRight 18th May 2011 15:19


Checking CSMU integrity (sealing) before powering up

Chris and GS

Quote:
Quote from Golf-Sierra:
As far as checking if there was water in the module prior to powering it up - would not the simplest way be to weigh it?

Nice one. Perhaps the experts can comment?
If i designed the "pressure vessel" i put a VERY SIMPLE SENSOR inside:

A humidity detector. There are several (one is VERY CHEAP) to implement it.

Not sure I see the point in trying to detect water/moisture inside the module when it is very low risk to open it and have a look.

Things other than water such as a cracked PCB that can also cause problems.

SaturnV 18th May 2011 15:20

bearfoil, for better or worse, your skepticism has not yet reached the level of a former poster on this board, who was not content to simply post an amalgamation of theories, propositions, facts, and conjecture on PPRuNe:

http://www.ntsb.org/Wiringcargodoor/...mithAAR182.pdf

(Note the sleight of hand on the domain.)

KBPsen 18th May 2011 15:22


If the final report contains some criticism of the crew, I suppose you will now be pointing back to these posts of yours and saying that your conspiracy theory is thereby proved ?
That is the beauty of conspiracy theories. Everything can be used to prove the theory. If the facts do not fit the conspiracy theory then the facts are part of the conspiracy and therefore proves the conspiracy. If facts do fit the theory then that also proves the conspiracy.

So much for keeping an open mind.

kilomikedelta 18th May 2011 15:22

Weighing recorders
 
What is the variation in weights of brand new recorders? How do you compensate for the lost paint chips and the missing bits of labels? The amount of salt water which would cause corrosion of the electronics is probably a very small percentage of the weight of the recorder.

HazelNuts39 18th May 2011 15:22


Originally Posted by grity
flying in future "sound and altitude" as backup system.....!

Perhaps the cockpit noise is somewhat sensitive to sideslip and AoA. The AF447 analysis can (will?) use IRS-derived groundspeed together with last known wind speed at cruise FL, and from meteo data at lower altitudes, or alternatively, airspeed derived from Weight and AoA. The principle is shown in this graphical illustration. The latter method may also be useable as backup system

Lonewolf_50 18th May 2011 15:41

For l@serdog

Lonewolf... I've also wondered about your question ".. why were they not able to regain control? They had 30,000+ feet in which to do so, based on FL selected." 1. The ACARS message at 2:12 seems to hint at an upset with the loss of the l@ser ring gyro integrity.
2. I wonder how much simulator time on upset recovery is spent by flight crews?
Avoidance of those situations is certainly stressed, but when it happens on a bumpy night in the middle of a cell with nothing to see outside the cockpit, that is a daunting task to put on anyone.
Many thanks, I italicized and numbered the two critical concerns that are hidden from the layman when people toss about the term "pilot error" without understanding contributors. My response is with the non-pilot in reader mind. Even sciolists may benefit from what follows.l :E

I had not remembered, nor quite grasped, from previous discussion that l@ser ring gyro integrity might be a system failure or malfunction facing the crew.

Note for the non-pilots on two words I use here. If you have a malfunctioning piece of equipment, sometimes a reset, or a bit of working with the equipment, or adjustment with its controlling knobs and switches, restores its operation. If you have an equipment failure, typically you don't get it back to functioning status until you land and the maintenance / engineering crew repair or replace whatever stopped working correctly.

The chance of l@ser ring gyro integrity failure (or malfunction) gives my many-pages-back-question on "tumbling gyros" part of an answer.

If I understand correctly, the l@ser ring gyro integrity being compromised leads to (may lead to?) unreliable attitude reference system on the pilot's display.

For the non-pilot reader.

If that happens in level flight, it's a matter of deliberate trouble shooting and dealing with the malfunction, and if needed, due to being in instrument conditions, using a partial panel scan by the flying pilot while the non flying pilot trouble shoots, resets, restores, whatever. If in less benign flight conditions, there's trouble ahead.

When the primary attitude reference instrument for flight in instrument conditions (which pilots are trained to refer to first, and to trust, when flying on instruments) is lost, or it gives false indications, it requires that the pilot use cross references to continue to fly in instrument conditions. Being good at this requires initial training, and practice. It's not easy, but if kept refreshed, it is a tool in every professional pilot's kit bag.

Here's the part that can kill you.

Until this failure or false indication is recognized, using this instrument as primary attitude reference (wings level or not, nose up or down) can lead to erroneous pilot inputs. (Think JFK, Jr., spiraling down off of Cape Cod due in part to not knowing how to correctly use, or to incorrectly using, flight instruments when flying in instrument conditions - no reference to outside horizon).

Once recognized, such a display failure requires the pilot(s) to transition to a partial panel scan to recover from what I assume in this case is an upset/out of control flight condition.

Even if, as might be the case, the attitude reference system might have been in "malfunction" rather than "failure" mode, the time constraint of falling in unstable flight can have precluded the crew being able to reset/restore the primary flight instrument (attitude reference) due to being up to their elbows in a partial panel, unusual attitude/upset/out of control recovery problem ... in turbulent air associated with a Tstorm. :eek: As l@aserdog notes, "when it happens on a bumpy night in the middle of a cell with nothing to see outside the cockpit, that is a daunting task to put on anyone." Pucker factor goes to 9.9 out of a possible 10 ...

If we go to the Rumors sub forum thread, I see "well, it's pilot error." If we get some of journalists involved, we get "pilot error," and if we get pilots talking, we get "how do you solve this flying problem, and are you prepared, trained, and experienced in this mode of flight?"

This takes me to the question (2) on what weight unusual attitudes and partial panel scans get in the sim training, and during refresher / annual / periodic training.

Does this vary by airline? I suspect so, but am ignorant of detail.

lomapaseo 18th May 2011 15:46

SaturnV


widebody and lomapaseo, if the preliminary read of the FDR had indicated unreliable air speed perhaps associated with pitot failure, would Airbus (or Boeing or Dassault) have sent out the telex phrased as Airbus did?

Respectfully I'll treat this as an honest question :)

I'll leave it to our seasoned speculators on this board to propose an answer.

I predict that with little thought they will deduce a coverup :E

Lonewolf_50 18th May 2011 15:54

loma:

IIRC, Airbus had already issued a service bulletin a couple of years ago (or an AD by BEA??) about pitot probes. If "nothing new to report" is what Airbus said, then even if FDR has indicated issues with A/S inputs, there had already been a remedy in the system for well over a year (nearly two or three?) to address that (possible) causal factor.

Have I missed a trick here? :confused:

jcjeant 18th May 2011 15:55

Hi,

Anyone who know the AF rules (SOP) concerning the maning of the flight deck ?
EG .. how many pilots minimun in flight deck
What rule if one pilot leave for some time the flight deck .. etc .. ?

snowfalcon2 18th May 2011 15:58

Lonewolf50:
But would a malfunction or failure of a gyro not show up on the FDR trace? And would Airbus in that case have sent out the AIT ?

Your scenario then seems to suggest initially an in-flight attitude upset beyond the gyro's limits, which then caused a "tumbling gyro" malfunction. Rather than a gyro malfunction leading to an attitude upset?

RR_NDB 18th May 2011 16:07

Slow motion evolution of recorders and pingers
 
GY,


This seems overly complicated and unnecessary given the low cost of solid-state memory. In fact the idea that the 'recorder' is manipulating (mixing and storing) the data once recorded seems astonishing to me... but then I suppose the design is some 20 years old or so (haven't checked that - it is a guess!).
It seems they designed this "architeture" to allow some flexibility in the a/c config. (microphones, etc.).

But i agree with you. IMO this shows there are "room for improvement". For example, why not a better fidelity in ALL channels (Nyquist) to allow an easier analysis. Memory chips are cheap like you mentioned.

On Pingers we will "soon" see in the market solutions that could avoid this ABSURD two years (3rd Interim report by summer) delay.

Turbine D 18th May 2011 16:09

grity,


there is a graphic for whigt and balance (CG limits) on s.10
the range for an A330-200 with 210t is from 17 to 39%

there is no advice that the stability is badly different in this range...
and no advise what is the most stable position of CG (24...26% ???)
Interestingly, I noticed the same thing you did and ask the same question to myself. If I interpret the A-300-200 for a 205 ton weight, they were operating within the limits, but right at the edge. For the -200 the limit is just under 38% and they were at somewhere between 37.3-37.8%. I would have to believe one would have better control (absent the computers) if the CG was as you suggested. The capability is there to pump the fuel either way, from or to the trim tanks. I am not sure how long it would take to pump the quantity of fuel to the center tank from the trim tank to equal a 24-26% CG. Tubby gave an estimate of the amount of fuel in the trim tank in his post #1253. However, that said, it could be pumped back to the trim tank after the perceived turbulent episode was over to regain the desired efficiency. Perhaps one or more of the A-300 pilots could comment on the pros and cons of this idea.

HazelNuts39 18th May 2011 16:13

RE: 3rd Interim report by summer;

I'm afraid "not before summer" means after summer - october?

Lemurian 18th May 2011 16:16

jcjeant,


Anyone who know the AF rules (SOP) concerning the maning of the flight deck ?
AirFrance provides each pilot with a foldable chamber pot so that they stay at all times in the flight deck.:rolleyes:
Of course, not much attention to the flight instruments is given at these times when one is on his /her paper throne as etiquette requires the other pilot to look to the side window.:ugh:


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