AF447 wreckage found
Plastic PPRuNer
Apologies for asking again.
Was not (at least) the standby Artificial Horizon working?
Would not the fact that it would have been showing mostly blue sky have given them a clue to the marked nose-up attitude?
And thereby an indication of incipient/actual stall?
Why wouldn't they have looked at it?
Was not (at least) the standby Artificial Horizon working?
Would not the fact that it would have been showing mostly blue sky have given them a clue to the marked nose-up attitude?
And thereby an indication of incipient/actual stall?
Why wouldn't they have looked at it?
Join Date: Jul 2002
Location: UK
Posts: 3,093
Likes: 0
Received 0 Likes
on
0 Posts
For what feels like the thousandth time, It's not better, not worse, just different.
Also, let's just examine your argument - you want the systems simple, but you advocate yokes and force-feedback. There is no way to implement force-feedback in a digital flight control system without making the system more complex and adding thousands more potential points of failure - that's just engineering reality.
Did you read the report?Is it you that doesnt understand whats been going on in the last 20 years?They couldnt fly the plane.They were automation-dependent and that dependence was condoned by both manufacturer and airline.
http://www.pprune.org/rumours-news/3...ys-airbus.html
This article came out a few months after AF447, but you can't say that Airbus have been blase about it, nor have they applied any pressure to have it viewed as pilot error and leave it at that.
@Franzl (below) - That's a valid opinion, sure. But I would recommend at least trying the systems out or making an in-depth effort to understand the design decisions that were made - and why they are made, before saying something "must" be changed. As yet, I've seen no evidence that either change you suggest would have helped in this situation or any other Airbus FBW incident, and seeing as there are thousands of the things flying people around the world, trouble-free, every day I'd say the design is as sound as any other as it stands - it's not perfect, but what system is?
[As always, caveat emptor - I'm not a pilot. But the fact remains that there are plenty of pilots on here that are either current on the FBW Airbus, have flown the FBW Airbus and are now on a different type, or are retired FBW Airbus pilots and very few of them have a negative thing to say about the control hardware or logic compared to other types. Several have also said that the aircraft is a dream to hand-fly, thus scotching any ideas about it being designed for automatic flight only.]
Last edited by DozyWannabe; 23rd Aug 2011 at 16:30.
Rananim
Of course.The pilots are the same.They dont change.Some are good,most are average, some are below average.
Quote:
RetiredF4 hit the nail on the head.
Quote:
Invent something new instead of those with the same or even improved feedback results, and we won´t be back in stone age, but hopefully in a more safer future.
Rananim
No,he did not hit the nail on the head. All commercial airliners are 2 man crew last time I checked.What better feedback is there than a great big control wheel beween your legs?Dont try to reinvent the wheel.It works and it works well.
Quote:
RetiredF4 hit the nail on the head.
Quote:
Invent something new instead of those with the same or even improved feedback results, and we won´t be back in stone age, but hopefully in a more safer future.
Rananim
No,he did not hit the nail on the head. All commercial airliners are 2 man crew last time I checked.What better feedback is there than a great big control wheel beween your legs?Dont try to reinvent the wheel.It works and it works well.
I can understand that and i´m with you concerning feedback what the other guy is doing with the stick. I´ve never flown a yoke, and i was always wondering how somebody can execute those tiny necessary commands i could do with the stick inmy F4. Later on i did the ATPL Sim Sessions in a caravelle simulator and missed my stick badly.
I think the SS design can improve to fullfill these tasks. That ranges from feedback to repositioning of the SS from the side consoles to the centre console. Sure some equipment can be moved from the center to elsewhere. The throttles only move some switches, however they are still designed as needing to move an oxcart. Or put the throttles amd trimwheels to the side controls, the interconection of those shouldnt be that difficult to achieve.
I agree with Safety Concerns, there will be no going back to the old design, but we need to get back the old functionality and interface quality of this old design.
Join Date: Aug 2009
Location: Germany
Age: 67
Posts: 1,777
Likes: 0
Received 0 Likes
on
0 Posts
Hi,
I asked also ...
Seem's the pilots of the AF447 and pilots here .. don't like to use the Stdby Horizon
Or if they use it ... they use it in an discriminatory manner .. they check it for leveling wings ( or make mayonnaise for AF447) but don't see blue color ..
Daltonism
Apologies for asking again.
Was not (at least) the standby Artificial Horizon working?
Would not the fact that it would have been showing mostly blue sky have given them a clue to the marked nose-up attitude?
And thereby an indication of incipient/actual stall?
Why wouldn't they have looked at it?
Was not (at least) the standby Artificial Horizon working?
Would not the fact that it would have been showing mostly blue sky have given them a clue to the marked nose-up attitude?
And thereby an indication of incipient/actual stall?
Why wouldn't they have looked at it?
Seem's the pilots of the AF447 and pilots here .. don't like to use the Stdby Horizon
Or if they use it ... they use it in an discriminatory manner .. they check it for leveling wings ( or make mayonnaise for AF447) but don't see blue color ..
Daltonism
Join Date: Jul 2002
Location: UK
Posts: 3,093
Likes: 0
Received 0 Likes
on
0 Posts
@jcjeant - That's funny, I seem to recall the Captain specifically directing the flight crew's attention towards the ISIS horizon according to the CVR. I don't think we'll ever know if the flight crew ever looked at it beforehand.
Join Date: Oct 2006
Location: Gone Flying...
Age: 63
Posts: 270
Likes: 0
Received 0 Likes
on
0 Posts
I agree with Safety Concerns, there will be no going back to the old design, but we need to get back the old functionality and interface quality of this old design.
Well, I also agree with this affirmation, there will be no going back to the old design, because it would cost a huge sum of money and effort, and would specially cost the "face" of Airbus Industrie's system design.
What bothers me, is not to see the need for the functionality and interface quality the old design used to have. To improve the tactile feed-back of what your aircraft is doing is to move forward. The challenge of today, would be to create a system much more "user-friendly" (Human Factors speaking) aimed at what would best suit the already identified weaknesses of pilot/machine interface.
When I say that if it was not for men to be never content with what they had achieved, we would still be in the Stone Age, is to put in practice the ideals of men and women like Da Vinci, Einstein, Neils Bohr, Marie Curie, etc., who had the virtue of being open minded and were not afraid of criticism once their goal was to do the things they already did well, but wanted to do better next time (and not get lazy under the glory of their achievements).
There is always room for progression and if to progress one would have to use old stuff like feed-back functionalities or tactile feed-back, so be it!
Regarding the use of the UAS memory items (5º/Climb Thrust) in CRZ, I do agree with PJ2's idea that it is not worth to destabilize an aircraft that is already flying well in present conditions. Pilots who are used to hand-fly their aircraft to TOC do know what ATT they are handling at those altitudes (never more than 3º/3.5º, even overpowered A310's would use no more than 3.5º when reaching TOC or changing altitudes). An ATT of 5º is sufficient to slowly decelerate an heavy bird and bring it to the onset of a stall.
Clandestino;
Thanks for keeping the dialogue on this drill alive. The disagreement on how to apply the drill in force at the time.
You're probably right but I'm not a test pilot and don't actually know how drills and checklists obtain the form they do. I do know that the UAS drill has many iterations throughout its history since it was first instituted after the Birgenair and Aeroperu crashes.
When the Airbus FCOM Bulletin and the UAS drill first emerged, a pitot (or static) failure was assumed to have occurred at takeoff as the two accidents had. Of course, it is an emergency under those circumstances and the guidance in the memorized drill was appropriate.
An ADR Disagree event occurred on an A330 as early as 1996. The characteristics were pitot icing, an undesired stall warning and a latching of Alternate law for the rest of the flight. I believe these events drove some of the changes which we see today regarding the stall warning, (inhibition above M0.866), the (10sec?) delay in latching Alternate Law, etc. Airbus issued Bulletin #11 dated October, 1997.
I don't know if an Unreliable Airspeed Drill/Checklist was in place at that time or not. The earliest drill I know of is November of 2002; there may be examples prior to this date.
Both FCOM Bulletin 11 and the UAS drill at the time, (found in 1.02.34 - Navigation) stated that the memorized pitch attitude and thrust setting were to be flown. The UAS drill qualified this by stating under "How to Apply This Procedure":
" - if the wrong speed or altitude information does not affect the safe conduct of the flight, first apply the ADR Check procedure to identify the faulty ADR(s) and switch it (them OFF. If necessary, enter the unreliable speed procedure, or severe turbulence table (if in cruise), to set the pitch and thrust corresponding to the current flight phase.
...
- if the safe conduct of the flight is affected (all the speed indications are unreliable, ro the wrong speed indication cannot not [sic] be positively identified):
- immediately apply the memory items: AP/FD/ATHR OFF, and fly the memory pitch - thrust settings";
- Then, once stabilzed, refer to the QRH in order to determine the pitch and thrust settings required by the current flight phase;
... " etc
There is no guidance as to what the meaning of "stabilized" is in this context. Does it mean, "stabilized in the (resulting) climb"?, or does it mean, "stabilized in level flight"?, because setting a pitch attitude of 5deg in cruise is going to result in a strong climb.
In my own experiment* the pitch to 5deg causes an initial climb rate of about 4000fpm with a commensurate decrease in airspeed even with thrust set in the CLB detent. It takes about two minutes to reach FL400 by which time the airspeed is around 200kts.
These numbers are nominal, and are in the same ballpark as those seen in the AF447 data.
Two minutes is not a long time as we know; by the time the QRH is brought out and the page found and numbers read, the airplane is already a long way from stable, level flight and is climbing while the energy level is reducing.
Later UAS drills are not materially different. However, two flight crew training manuals I am aware of states,
"A330/A340 FLIGHT CREW TRAINING MANUAL - ABNORMAL OPERATIONS, NAVIGATION
So, although the drill/checklist state that setting 5deg of pitch "protects" the airplane from stall, I see the opposite, and I can't see a test pilot actually thinking this was a better solution than remaining level while the QRH was brought out.
One can certainly re-establish stable, level flight by immediately flying the QRH pitch and thrust settings, but what has been lost is the situational awareness of what one's speed is. We know that at cruise flight levels there is not a lot of reserve power. So instead of staying level and keeping the pitch and thrust that was "successful" immediately prior to the loss of airspeed information, the crew loses that awareness by climbing and losing energy, which must be regained.
I would argue that it is not the "Is the safety of flight impacted?" that should be the qualifying condition, but the flight phase and the altitude at which the failure occurs. That removes the possibly-subjective assessment of whether one's aircraft is in jeopardy or immediate danger, and instead outlines those conditions in which the aircraft either is, or is not in immediate danger, which is predicated on the Thrust Reduction Altitudes and the Takeoff flight phase.
At cruise flight phase the airplane isn't in immediate danger if the airspeed information is lost. One has pitch, altitude, VSI and thrust indications from which stable flight can be maintained while the pitot's and ADRs sort themselves out, or if they don't, one has a stable airplane in level flight from which to troubleshoot the ADRs.
This emminently satisfies the first rule of aviation - "Aviate". Once the aircraft is under full control, then carry on with the drills, by first announcing them so that everyone knows what you're doing and can monitor and provide assistance. One continues to Navigate which means ensuring headings are suitable while the abnormals are being looked after, and one continues to Communicate which means using standard calls to announce the abnormal or the drill and, where an action is irreversible, (engine shutdown, for example), confirmation from the other crew member, (PF) before taking action.
To address Mountain Bear's earlier point, none of this is the result of "hindsight bias" or second-guessing the crew. I am well aware of the issue and have written about it on PPRuNe. I don't claim immunity from the bias but what is the boundary between hindsight, and examining what occurred and is known in the data? It isn't easy to establish. We have to start somewhere and then remain cautious. While we may not know what the PF saw on his PFD or elsewhere, there is nothing which should have prevented the crew from carrying out these SOPs, which are also designed by test pilots and manufacturers as well as individual airlines. The question will be, Why were these actions not carried out in the manner trained?, which is a reasonable question to ask for the Human Factors Group.
I am glad that the discussion on this continues as I think it is a material factor in this accident. We do not know what was displayed on the PF's PFD, (although we know that the BEA is pursuing this possibly through the QAR) and we do not know what UAS training was provided or what reactions where recalled.
But the fact that there is some disagreement in how this should be done, means that at least a discussion is warranted and useful. I have yet to see or hear a good reason why flight with pitch and thrust settings which existed prior to the loss of airspeed data should not be maintained and instead the aircraft pitch set, by rote, to 5deg and then without delay, (as per the FCTM remarks), the QRH Procedure to level off and troubleshoot the problem" must be done to avoid exceeding aircraft speed limits, (which we must assume means both high and low speed boundaries).
Thanks again, Clandestino. Agreement isn't the goal, but thinking about the way this drill and checklist is designed and intended to be executed, is.
Thanks for keeping the dialogue on this drill alive. The disagreement on how to apply the drill in force at the time.
Originally Posted by Clandestino in post #3167
Emergency procedures are not written by company lawyers, they are written by test pilots.
When the Airbus FCOM Bulletin and the UAS drill first emerged, a pitot (or static) failure was assumed to have occurred at takeoff as the two accidents had. Of course, it is an emergency under those circumstances and the guidance in the memorized drill was appropriate.
An ADR Disagree event occurred on an A330 as early as 1996. The characteristics were pitot icing, an undesired stall warning and a latching of Alternate law for the rest of the flight. I believe these events drove some of the changes which we see today regarding the stall warning, (inhibition above M0.866), the (10sec?) delay in latching Alternate Law, etc. Airbus issued Bulletin #11 dated October, 1997.
I don't know if an Unreliable Airspeed Drill/Checklist was in place at that time or not. The earliest drill I know of is November of 2002; there may be examples prior to this date.
Both FCOM Bulletin 11 and the UAS drill at the time, (found in 1.02.34 - Navigation) stated that the memorized pitch attitude and thrust setting were to be flown. The UAS drill qualified this by stating under "How to Apply This Procedure":
" - if the wrong speed or altitude information does not affect the safe conduct of the flight, first apply the ADR Check procedure to identify the faulty ADR(s) and switch it (them OFF. If necessary, enter the unreliable speed procedure, or severe turbulence table (if in cruise), to set the pitch and thrust corresponding to the current flight phase.
...
- if the safe conduct of the flight is affected (all the speed indications are unreliable, ro the wrong speed indication cannot not [sic] be positively identified):
- immediately apply the memory items: AP/FD/ATHR OFF, and fly the memory pitch - thrust settings";
- Then, once stabilzed, refer to the QRH in order to determine the pitch and thrust settings required by the current flight phase;
... " etc
There is no guidance as to what the meaning of "stabilized" is in this context. Does it mean, "stabilized in the (resulting) climb"?, or does it mean, "stabilized in level flight"?, because setting a pitch attitude of 5deg in cruise is going to result in a strong climb.
In my own experiment* the pitch to 5deg causes an initial climb rate of about 4000fpm with a commensurate decrease in airspeed even with thrust set in the CLB detent. It takes about two minutes to reach FL400 by which time the airspeed is around 200kts.
These numbers are nominal, and are in the same ballpark as those seen in the AF447 data.
Two minutes is not a long time as we know; by the time the QRH is brought out and the page found and numbers read, the airplane is already a long way from stable, level flight and is climbing while the energy level is reducing.
Later UAS drills are not materially different. However, two flight crew training manuals I am aware of states,
"A330/A340 FLIGHT CREW TRAINING MANUAL - ABNORMAL OPERATIONS, NAVIGATION
Rev.No.01
1st February 2007
MEMORY ITEMS
The flight crew applies the memory items, if the safe conduct of the flight is affected. The memory items allow to rapidly establish safe flight conditions in all phases of flight and in all aircraft configurations (weight and slats/flaps).
1st February 2007
MEMORY ITEMS
The flight crew applies the memory items, if the safe conduct of the flight is affected. The memory items allow to rapidly establish safe flight conditions in all phases of flight and in all aircraft configurations (weight and slats/flaps).
The flight crew must apply the memory items, if they have a doubt on their ability to safely fly the aircraft in the short term with the current parameters, ie:
• The flight crew has lost situation awareness, or
• The current pitch and thrust are not appropriate for the current flight conditions, or
• The aircraft has an unexpected flight path for the current flight conditions.
• The flight crew has lost situation awareness, or
• The current pitch and thrust are not appropriate for the current flight conditions, or
• The aircraft has an unexpected flight path for the current flight conditions.
When the PF has stabilized the target pitch and thrust values, the flight crew applies the QRH procedure to level off and troubleshoot the problem. The flight crew must apply the QRH procedure without delay, because flying with the memory pitch/thrust values for an extended period of time can lead to exceed the aircraft speed limits.
Note: The flight crew must respect the STALL warning."
So, although the drill/checklist state that setting 5deg of pitch "protects" the airplane from stall, I see the opposite, and I can't see a test pilot actually thinking this was a better solution than remaining level while the QRH was brought out.
One can certainly re-establish stable, level flight by immediately flying the QRH pitch and thrust settings, but what has been lost is the situational awareness of what one's speed is. We know that at cruise flight levels there is not a lot of reserve power. So instead of staying level and keeping the pitch and thrust that was "successful" immediately prior to the loss of airspeed information, the crew loses that awareness by climbing and losing energy, which must be regained.
I would argue that it is not the "Is the safety of flight impacted?" that should be the qualifying condition, but the flight phase and the altitude at which the failure occurs. That removes the possibly-subjective assessment of whether one's aircraft is in jeopardy or immediate danger, and instead outlines those conditions in which the aircraft either is, or is not in immediate danger, which is predicated on the Thrust Reduction Altitudes and the Takeoff flight phase.
At cruise flight phase the airplane isn't in immediate danger if the airspeed information is lost. One has pitch, altitude, VSI and thrust indications from which stable flight can be maintained while the pitot's and ADRs sort themselves out, or if they don't, one has a stable airplane in level flight from which to troubleshoot the ADRs.
This emminently satisfies the first rule of aviation - "Aviate". Once the aircraft is under full control, then carry on with the drills, by first announcing them so that everyone knows what you're doing and can monitor and provide assistance. One continues to Navigate which means ensuring headings are suitable while the abnormals are being looked after, and one continues to Communicate which means using standard calls to announce the abnormal or the drill and, where an action is irreversible, (engine shutdown, for example), confirmation from the other crew member, (PF) before taking action.
To address Mountain Bear's earlier point, none of this is the result of "hindsight bias" or second-guessing the crew. I am well aware of the issue and have written about it on PPRuNe. I don't claim immunity from the bias but what is the boundary between hindsight, and examining what occurred and is known in the data? It isn't easy to establish. We have to start somewhere and then remain cautious. While we may not know what the PF saw on his PFD or elsewhere, there is nothing which should have prevented the crew from carrying out these SOPs, which are also designed by test pilots and manufacturers as well as individual airlines. The question will be, Why were these actions not carried out in the manner trained?, which is a reasonable question to ask for the Human Factors Group.
I am glad that the discussion on this continues as I think it is a material factor in this accident. We do not know what was displayed on the PF's PFD, (although we know that the BEA is pursuing this possibly through the QAR) and we do not know what UAS training was provided or what reactions where recalled.
But the fact that there is some disagreement in how this should be done, means that at least a discussion is warranted and useful. I have yet to see or hear a good reason why flight with pitch and thrust settings which existed prior to the loss of airspeed data should not be maintained and instead the aircraft pitch set, by rote, to 5deg and then without delay, (as per the FCTM remarks), the QRH Procedure to level off and troubleshoot the problem" must be done to avoid exceeding aircraft speed limits, (which we must assume means both high and low speed boundaries).
Thanks again, Clandestino. Agreement isn't the goal, but thinking about the way this drill and checklist is designed and intended to be executed, is.
Last edited by PJ2; 27th Aug 2011 at 05:49.
Per Ardua ad Astraeus
Join Date: Mar 2000
Location: UK
Posts: 18,579
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Mac Post 3173
Apologies for asking again.
Was not (at least) the standby Artificial Horizon working?
Would not the fact that it would have been showing mostly blue sky have given them a clue to the marked nose-up attitude?
And thereby an indication of incipient/actual stall?
Why wouldn't they have looked at it?
Was not (at least) the standby Artificial Horizon working?
Would not the fact that it would have been showing mostly blue sky have given them a clue to the marked nose-up attitude?
And thereby an indication of incipient/actual stall?
Why wouldn't they have looked at it?
@BOAC:
I don't think we have any reason to suspect that any of the attitude indicators were not functioning properly - including the *** big ones in front of the pilots - unless someone is hiding something.
Unless the BEA is simply being coservative and admitting that it's unknown.
That said, were you and I in Vegas, I suspect we'd both bet the same on the likelihood of the PFD, RH, being functional. Were it not, I suspect at least something on CVR would have come up, but we do have the PNF switching to 3 ... perhaps a sign of non verbal communication regarding PFD being suspect?
Unknown.
I don't think we have any reason to suspect that any of the attitude indicators were not functioning properly - including the *** big ones in front of the pilots - unless someone is hiding something.
That said, were you and I in Vegas, I suspect we'd both bet the same on the likelihood of the PFD, RH, being functional. Were it not, I suspect at least something on CVR would have come up, but we do have the PNF switching to 3 ... perhaps a sign of non verbal communication regarding PFD being suspect?
Unknown.
Unless the BEA is simply being coservative and admitting that it's unknown.
The roll axis traces in the first half minute after AP disconnect suggest the PF was struggling to get hold in this period, with several regular cycles of overcontrol left/right.
I cannot envisage this happening unless he had a working display as reference ... too regular.
Proof positive - or not?
Join Date: Aug 2011
Location: Home
Posts: 8
Likes: 0
Received 0 Likes
on
0 Posts
Mac the knife
It seems interesting to look at the normal and stand-by instruments mounted on 'Airbus A380
------------------
The ADIRS is composed of 3 Air Data and Inertial
Reference Units (ADIRUs).
>The Air Data (AD) section computes primary air data
parameters using data from different probes installed
on the aircraft fuselage:
>1 Multi-Function Probe (MFP) per ADIRU
provides total pressure (Pt), Total Air
Temperature (TAT) and Angle-of-Attack (AOA)
Measurements
>1 Side Slip Angle (SSA) probe per ADIRU
provides the sideslip angle
>2 Integrated Static Probes (ISPs) per ADIRU
provide the static pressure (Ps)
-----------------
The Integrated Standby Instrument System (ISIS)
provides backup flight and navigation displays in the case
of an ADIRS, FMS or CDS failure.
The ISIS is composed of:
2 independent ISIS units,
the Standby Flight Display (SFD) unit and
Standby Navigation Display (SND) unit
1 standby pitot probe (Pt)
2 standby static probes (Ps)
-Internal gyros (attitude).
In normal configuration:
-The SFD unit computes and displays air data and
inertial reference parameters (SFD)
-The SND unit computes and displays navigation and
flight plan information (SND).
Each unit can perform all the ISIS functions.
---------------
Now on A380 there are 3 multifunction probes and 1 normal probe air speed for ISIS?
and how many probes and static ports are mounted on the sides of the fuselage?
.
Apologies for asking again.
Was not (at least) the standby Artificial Horizon working?
Would not the fact that it would have been showing mostly blue sky have given them a clue to the marked nose-up attitude?
And thereby an indication of incipient/actual stall?
Why wouldn't they have looked at it?
Was not (at least) the standby Artificial Horizon working?
Would not the fact that it would have been showing mostly blue sky have given them a clue to the marked nose-up attitude?
And thereby an indication of incipient/actual stall?
Why wouldn't they have looked at it?
------------------
The ADIRS is composed of 3 Air Data and Inertial
Reference Units (ADIRUs).
>The Air Data (AD) section computes primary air data
parameters using data from different probes installed
on the aircraft fuselage:
>1 Multi-Function Probe (MFP) per ADIRU
provides total pressure (Pt), Total Air
Temperature (TAT) and Angle-of-Attack (AOA)
Measurements
>1 Side Slip Angle (SSA) probe per ADIRU
provides the sideslip angle
>2 Integrated Static Probes (ISPs) per ADIRU
provide the static pressure (Ps)
-----------------
The Integrated Standby Instrument System (ISIS)
provides backup flight and navigation displays in the case
of an ADIRS, FMS or CDS failure.
The ISIS is composed of:
2 independent ISIS units,
the Standby Flight Display (SFD) unit and
Standby Navigation Display (SND) unit
1 standby pitot probe (Pt)
2 standby static probes (Ps)
-Internal gyros (attitude).
In normal configuration:
-The SFD unit computes and displays air data and
inertial reference parameters (SFD)
-The SND unit computes and displays navigation and
flight plan information (SND).
Each unit can perform all the ISIS functions.
---------------
Now on A380 there are 3 multifunction probes and 1 normal probe air speed for ISIS?
and how many probes and static ports are mounted on the sides of the fuselage?
.
Join Date: Aug 2005
Location: fl
Posts: 2,525
Likes: 0
Received 0 Likes
on
0 Posts
I guess noone can figure out why they didn't just hold their previous attitude, about 2.5 degrees up and about 85% N1 and get UAS checklist instead of pulling up into a stall at high altitude. If the low time PF didn't know any better why did the PNF let him continue, I don't care who was designated captain. Neither one had a clue what they were doing. Didn't they teach them that in Alt law you have no stall protection? Couldn't they have figured that out themselves? No normal law, no stall protection.
Join Date: Dec 2007
Location: Cornwall-on-Hudson, New York
Posts: 875
Likes: 0
Received 0 Likes
on
0 Posts
I guess noone can figure out why they didn't just hold their previous attitude, about 2.5 degrees up and about 85% N1 and get UAS checklist instead of pulling up into a stall at high altitude. If the low time PF didn't know any better why did the PNF let him continue, I don't care who was designated captain. Neither one had a clue what they were doing. Didn't they teach them that in Alt law you have no stall protection? Couldn't they have figured that out themselves? No normal law, no stall protection.
Join Date: Aug 2005
Location: fl
Posts: 2,525
Likes: 0
Received 0 Likes
on
0 Posts
I know it has been brought up many times but posts in the past have suggested it was not recoverable by any crew. Indicating it wasn't entirely their fault. I disagree. It was their fault. Airbus made it easy for them to do what they did but it was their fault. I think pilots of low experience thought the Airbus couldn't stall so disregarded normal flying rules and thought no matter how hard you pulled back on the SS it wouldn't stall. That only works in normal law. They were in alternate law.
bubbers44;
Below is a typical CBT image from the late 90's. Alternate Law is covered very well in any Airbus course I've seen or for which I've had access to the training materials.
Didn't they teach them that in Alt law you have no stall protection?
Join Date: Apr 2008
Location: HK
Posts: 513
Likes: 0
Received 0 Likes
on
0 Posts
Bubbers44
To help you think it is a normal A/C without stall protection!
I personally think this will eventually come down to inappropriate inputs PRIOR to the stall and having "looked" at the scenario you have to really hold the aft input to GET the A/C into that position. Extremely high rates of descent 15,000+ and the recovery will require at least 15degrees + nose down and TOGA, once the nose is down.
However during the entry the STALL warning is continually "sounding" and even if you had just let go of the sidestick, after the initial input, the stall warning stops and an extreme attitude is NOT achieved. You have to HOLD it in.
Having got themselves into the deep stall then things would have been very confusing, so we can perhaps understand why they did not know what was going on, but the A/C should not have got there in the first place. This is NOT an "Airbus" problem but perhaps a "pilot" problem. Difficult as it is to say and we always defend our profession but we do sometimes make mistakes / errors and I have made a few in my time.
The only good thing to come out of this, at the sad cost of many lives and as we used to say when I was in the Military "I learnt about flying from that!", is that I hope all of us "pilots" are now thinking about what WE would do in our A/C be it an Airbus / Boeing and we had an UAS situation at night and at altitude manually flying.
To help you think it is a normal A/C without stall protection!
I personally think this will eventually come down to inappropriate inputs PRIOR to the stall and having "looked" at the scenario you have to really hold the aft input to GET the A/C into that position. Extremely high rates of descent 15,000+ and the recovery will require at least 15degrees + nose down and TOGA, once the nose is down.
However during the entry the STALL warning is continually "sounding" and even if you had just let go of the sidestick, after the initial input, the stall warning stops and an extreme attitude is NOT achieved. You have to HOLD it in.
Having got themselves into the deep stall then things would have been very confusing, so we can perhaps understand why they did not know what was going on, but the A/C should not have got there in the first place. This is NOT an "Airbus" problem but perhaps a "pilot" problem. Difficult as it is to say and we always defend our profession but we do sometimes make mistakes / errors and I have made a few in my time.
The only good thing to come out of this, at the sad cost of many lives and as we used to say when I was in the Military "I learnt about flying from that!", is that I hope all of us "pilots" are now thinking about what WE would do in our A/C be it an Airbus / Boeing and we had an UAS situation at night and at altitude manually flying.
Join Date: Jun 2010
Location: USA
Posts: 245
Likes: 0
Received 0 Likes
on
0 Posts
Yes, I agree, keep a stable attitude and power, get out the UAS checklist, fine tune it a bit and fly out of the icing.
The most dangerous thing about comments like your bubbers44 is that everyone starts flying in response to the last accident so that the next accident, once again, takes everyone by surprise. Being scared of one's shadow is the worst possible outcome.