AF 447 Search to resume
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My initial comment on the loss of electrics lacked clarity and thanks to all for correcting me.
What I’m really getting at is pulling the plug on something that provides all your necessary flight information and the cause might be behind a panel.
Something that didn’t come across in the calm cockpit shown in the recent BBC documentary was just what it’s like to fly in a cocktail shaker conditions AF447 may have been flying through.
The initial AF perhaps knee-jerk statement was – it may have been struck by lightning, yes possible but more important where, it may have taken out some important wiring.
Connectors shouldn’t but can come adrift, wiring can chafe and short, circuit boards can fracture.
I presume that a PFD failure requires a complete circuit to generate a failure message.
Basically with PFD’s all you eggs are in one basket and I’m going to stick with the opinion that this flight crew lost more than just their airspeed indication
What I’m really getting at is pulling the plug on something that provides all your necessary flight information and the cause might be behind a panel.
Something that didn’t come across in the calm cockpit shown in the recent BBC documentary was just what it’s like to fly in a cocktail shaker conditions AF447 may have been flying through.
The initial AF perhaps knee-jerk statement was – it may have been struck by lightning, yes possible but more important where, it may have taken out some important wiring.
Connectors shouldn’t but can come adrift, wiring can chafe and short, circuit boards can fracture.
I presume that a PFD failure requires a complete circuit to generate a failure message.
Basically with PFD’s all you eggs are in one basket and I’m going to stick with the opinion that this flight crew lost more than just their airspeed indication
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Initially the PFD's (display) are denied FD (director), it was selected but unavailable. Next comes the failure of the FPV (bird), and all orientation by PFD is eliminated. This implies to me that all attitude (and airspeed) values are not transmitted to the screen; bear
Jeff
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Mack,
I do software that is touch screen based for broadcast stations. I note that there are companies making "industrial", as in ruggedized, touch screens as large as 1920x1200 pixels and typically about 20.5" by 12.75" viewing area. A pair of such beasties in front of each seat might make a display you didn't have to page through.
I get the chills every time I think of a poor fellow in a cockpit with the important display of the moment up when something pickles. "Er, let me see, press exit, exit, exit, frimble, wubble, mixup, pickle-solution." By the time he's done that he has a missile up his tailpipe. (I have a background doing DoD work in my bad old days.)
The feeling persists. A basic set of critical gauges and displays must always be present. I have a suspicion that larger display real-estate might make a difference. I am relatively certain that the 'surprise' solution, automatically flipping the display to the important one, is not a good one. The brief disorientation could also be fatal. But, just maybe, it might be less fatal.
I observe that when the brown stuff starts to shred in the impeller more problems than major problem often appear. Picking the one true problem might not work automatically. If not, a large display could mitigate the problem a little.
Am I on to something here?
I do software that is touch screen based for broadcast stations. I note that there are companies making "industrial", as in ruggedized, touch screens as large as 1920x1200 pixels and typically about 20.5" by 12.75" viewing area. A pair of such beasties in front of each seat might make a display you didn't have to page through.
I get the chills every time I think of a poor fellow in a cockpit with the important display of the moment up when something pickles. "Er, let me see, press exit, exit, exit, frimble, wubble, mixup, pickle-solution." By the time he's done that he has a missile up his tailpipe. (I have a background doing DoD work in my bad old days.)
The feeling persists. A basic set of critical gauges and displays must always be present. I have a suspicion that larger display real-estate might make a difference. I am relatively certain that the 'surprise' solution, automatically flipping the display to the important one, is not a good one. The brief disorientation could also be fatal. But, just maybe, it might be less fatal.
I observe that when the brown stuff starts to shred in the impeller more problems than major problem often appear. Picking the one true problem might not work automatically. If not, a large display could mitigate the problem a little.
Am I on to something here?
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JD-EE,
Do you read French?
You might enjoy "Concorde, Essais et Batailles" by André Turcat.
He was the Flight Test Director at Aérospatiale at the start of the Concorde programme, and also the first one to fly the aircraft.
There's almost an entire chapter about flight instruments, and presentation formats, etc. that's worth reading.
This was the age of the "clocks", although some were tape instruments, and the three-hand altimeter was becoming a thing of the past.
Reading your post, I was suddenly wondering how much of the present-day glass cockpits are still designed by pilots, and how much by geeks accustomed to flipping through browser pages, clicking on icons, and using 'Google'.
CJ
Do you read French?
You might enjoy "Concorde, Essais et Batailles" by André Turcat.
He was the Flight Test Director at Aérospatiale at the start of the Concorde programme, and also the first one to fly the aircraft.
There's almost an entire chapter about flight instruments, and presentation formats, etc. that's worth reading.
This was the age of the "clocks", although some were tape instruments, and the three-hand altimeter was becoming a thing of the past.
Reading your post, I was suddenly wondering how much of the present-day glass cockpits are still designed by pilots, and how much by geeks accustomed to flipping through browser pages, clicking on icons, and using 'Google'.
CJ
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flying in the center of a such big cell at those latitudes doesn't give you any chance to fly out of it alive...no matter if all the instruments are working or not ..why they flew in there?looking on the radar tracks all the other aircrafts avoided that big cell...
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FPV
Hyperveloce, could you help with this:
You quote Interim Report No. 2 p. 41. stating that "No message present in the CFR indicates the loss of displays or of inertial information (attitudes)."
Same report on p.36 states: "This message indicates that the flight path vector (FPV) function is selected but unavailable."
From reading other forums, it appears that FPV is useful in unreliable airspeed situations.
Just trying to understand why this is not an inconsistency---nothing else.
You quote Interim Report No. 2 p. 41. stating that "No message present in the CFR indicates the loss of displays or of inertial information (attitudes)."
Same report on p.36 states: "This message indicates that the flight path vector (FPV) function is selected but unavailable."
From reading other forums, it appears that FPV is useful in unreliable airspeed situations.
Just trying to understand why this is not an inconsistency---nothing else.
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Bird
Besides, in such a situation, usefull versus misleading parameters are given page 54 of the interim report:
This briefings booklet also provides a list of points that can help or affect the
accomplishment of the emergency manoeuvre and indicates the following in
particular:
-The factors identified as aids are: ground speeds, GPS altitude, radioaltimetric
height and STALL warning;
-The following factors, however, could be sources of confusion and
cause stress: unreliability of the FPV and of the vertical speed if the
altitude indications are affected, incorrect primary information without
any associated message on the ECAM, presence of alarms (false or real,
overspeed for example);
-The key points presented for the correct management of the situation are:
detection of the problems, interpretation of the alarms and coordination
in processing.
accomplishment of the emergency manoeuvre and indicates the following in
particular:
-The factors identified as aids are: ground speeds, GPS altitude, radioaltimetric
height and STALL warning;
-The following factors, however, could be sources of confusion and
cause stress: unreliability of the FPV and of the vertical speed if the
altitude indications are affected, incorrect primary information without
any associated message on the ECAM, presence of alarms (false or real,
overspeed for example);
-The key points presented for the correct management of the situation are:
detection of the problems, interpretation of the alarms and coordination
in processing.
PS) does the BEA formulation "There was no search for display of an attitude of 5°" refer to the application of the pich & thrust procedure ? (p 52 of the interim report #2, analysis of past cases of Pitot freezing events).
Last edited by Hyperveloce; 21st Jun 2010 at 14:48. Reason: PS question about the implementation of the pich & thrust procedure during past UAS
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Such Big Cell ... ?
Which one ?
Were you there butterfly68 ?
The BEA choose to not represent the tracks of two flights using the same airway that AF447 used. It appears that those two aircrafts have been through the same big red area that you like to call "that big cell" but managed to proceed to destination.
Do you have any other comment ?
Were you there butterfly68 ?
The BEA choose to not represent the tracks of two flights using the same airway that AF447 used. It appears that those two aircrafts have been through the same big red area that you like to call "that big cell" but managed to proceed to destination.
Do you have any other comment ?
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it was just a consideration..the other 2 aircrafts ( I didnt know about them because they are not shown) maybe overflew the core of the cell, you know .. 2000 feet only or more can make huge big difference and the cell was really wide..
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Originally Posted by butterfly68
flying in the center of a such big cell
Originally Posted by hyperveloce
does the BEA formulation "There was no search for display of an attitude of 5°" refer to the application of the pitch & thrust procedure ?
HN39
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At 350 no chance to survive the monster but at 370 nothing to worry about ... I'm not too sure to follow here your logic butterfly68 ?
Maybe there is a question to be asked by the so called journalists to the so called BEA ...
I didnt know about them because they are not shown
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Note that is not known definitely what altitude AF447 was at. The flight plan was to be at FL370, from
Air France 447 - AFR447 - A detailed meteorological analysis - Satellite and weather data
but it has been asserted before that they would not have followed the plan and climbed from FL350 without ATC approval.
If you look at the 10min ACARS positions graphically plotted here
Flight Paths of Flight AF 447 and of the flights that crossed the zone around the same time
and in detail for AF447
http://www.bea.aero/fr/enquetes/vol....data/AF447.txt
and assume exact times there is a slightly shorter sector between 01:50 and 02:00 which could indicate a change? Could also be due to a 15 second shorter time interval/ change in head winds etc. While FL370 may have been helpful to avoid the "SALPO storm" it would not be much use for the "Main MCS cluster"
from the very early analysis by Tim Vasquez
Air France 447 - AFR447 - A detailed meteorological analysis - Satellite and weather data
Later 'official' versions available are by BEA/ France Meteo
The locked rudder limit is stated by BEA to be M0.80, but you have to guess temperature profile inside the CB to get altitude estimate at approx -40 degrees - it seems to have been very hot over the equator.
Air France 447 - AFR447 - A detailed meteorological analysis - Satellite and weather data
but it has been asserted before that they would not have followed the plan and climbed from FL350 without ATC approval.
If you look at the 10min ACARS positions graphically plotted here
Flight Paths of Flight AF 447 and of the flights that crossed the zone around the same time
and in detail for AF447
http://www.bea.aero/fr/enquetes/vol....data/AF447.txt
and assume exact times there is a slightly shorter sector between 01:50 and 02:00 which could indicate a change? Could also be due to a 15 second shorter time interval/ change in head winds etc. While FL370 may have been helpful to avoid the "SALPO storm" it would not be much use for the "Main MCS cluster"
from the very early analysis by Tim Vasquez
Air France 447 - AFR447 - A detailed meteorological analysis - Satellite and weather data
Later 'official' versions available are by BEA/ France Meteo
The locked rudder limit is stated by BEA to be M0.80, but you have to guess temperature profile inside the CB to get altitude estimate at approx -40 degrees - it seems to have been very hot over the equator.
Last edited by sensor_validation; 22nd Jun 2010 at 12:56.
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butterfly68, the two flights were a Lufthansa 747 (preceding AF447) and an Iberia A340 (following AF447). Their deviations from the track are described in the first interim BEA report. However, the second interim report, for reasons unknown, does not include the plot of their deviations. Both flights did deviate from the track, one to the left and one to the right.
@sensor
The graphic depicted shows estimate that 447 penetrated thunderstorm in upper third, with tops at 50K and above.
AIM 7-1-28 and 7-1-29 come to mind.
An old rule of thumb that was once taught: if going through a T Storm, penetrate in bottom third. Is this still conventional wisdom, prevailing attitude in re thunderstorms (with avoidance being the normal default position ... )
Insofar as considering "going over" a T Storm, a course of action perhaps considered in this case, can the A 330 fly above 50K?
The wiki page entry shows a service ceiling of 41,100 ft. Is that correct?
The graphic depicted shows estimate that 447 penetrated thunderstorm in upper third, with tops at 50K and above.
AIM 7-1-28 and 7-1-29 come to mind.
An old rule of thumb that was once taught: if going through a T Storm, penetrate in bottom third. Is this still conventional wisdom, prevailing attitude in re thunderstorms (with avoidance being the normal default position ... )
Insofar as considering "going over" a T Storm, a course of action perhaps considered in this case, can the A 330 fly above 50K?
The wiki page entry shows a service ceiling of 41,100 ft. Is that correct?
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Originally Posted by Lonewolf 50
The wiki page entry shows a service ceiling of 41,100 ft. Is that correct?
Thanks, Hazel, no way they could have gone over that second build up.
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Hazelnuts39
Per your service ceiling for 447 (actual), one concludes this flight was bumping at trouble, saved only by extra mach (.82). With "extra" speed to "burn", will this autopilot "hunt"? A gentle rolly coaster at 37,000 could get critical if the PF allows automatic hunting to maintain a/s/altitude, no? If the upsy downsy causes a trip out, isn't the PF in a crapshoot to ascertain where and when to input controls? A PIO could follow an APIO, yes? Isn't it up to chance (possibly) whether it's STALL or overspeed at the beginning (continuation) of upset?
much respect,
bear
Per your service ceiling for 447 (actual), one concludes this flight was bumping at trouble, saved only by extra mach (.82). With "extra" speed to "burn", will this autopilot "hunt"? A gentle rolly coaster at 37,000 could get critical if the PF allows automatic hunting to maintain a/s/altitude, no? If the upsy downsy causes a trip out, isn't the PF in a crapshoot to ascertain where and when to input controls? A PIO could follow an APIO, yes? Isn't it up to chance (possibly) whether it's STALL or overspeed at the beginning (continuation) of upset?
much respect,
bear
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Are there a subset of failures where ACARS would stop but all flight critical systems continue to function.
Here are a few thoughts:
1. Lets give credit to the men on the flight deck that they were able to establish pitch/power to take manual control of the flight
2. Lets give credit to the machine and its designers that the failure of pitots (albeit all three of them) will not prompt the airplane to simply fall out of the sky.
3. Lets give credit to the men and women of the search operation.
4. Finally, lets give credit to BEA for its analysis.
If we do the above, we have an important piece of evidence we cannot overlook. The aircraft is not in the area we looked in and so, she continued flying for far longer than we are expecting.
Lets say the pilots established pitch/power. What next? Is it possible to re-engage automatics in the degraded law once they are out of the woods. Or, were they left with flying pitch/power without KIAS on the night flight all the way to Paris. Under such circumstances, would they have opted to turn back and fly to the nearest land mass. Would they have tried to ditch?
Here are a few thoughts:
1. Lets give credit to the men on the flight deck that they were able to establish pitch/power to take manual control of the flight
2. Lets give credit to the machine and its designers that the failure of pitots (albeit all three of them) will not prompt the airplane to simply fall out of the sky.
3. Lets give credit to the men and women of the search operation.
4. Finally, lets give credit to BEA for its analysis.
If we do the above, we have an important piece of evidence we cannot overlook. The aircraft is not in the area we looked in and so, she continued flying for far longer than we are expecting.
Lets say the pilots established pitch/power. What next? Is it possible to re-engage automatics in the degraded law once they are out of the woods. Or, were they left with flying pitch/power without KIAS on the night flight all the way to Paris. Under such circumstances, would they have opted to turn back and fly to the nearest land mass. Would they have tried to ditch?
Why would the pilots ditch if the engines were still working and there was fuel aboard?