Interesting note about AA Airbus crash in NYC

[airsupport]

Originally Posted by barit1

I think (but cannot say for sure) that the "surface" referred to by NTSB is the fracture surface. That's the surface the material science people are interested in.
See the early NTSB releases from last year's Chalk's G-73T crash - they included photos of the lower spar cap fracture surface.

IF that is what they mean, why don't they say that.

I guess because they want to make the report as ambiguous as possible, and aid in the cover up of the facts.

I will mention this at the picnic.

[AirRabbit]

Originally Posted by airsupport

Good idea.
At that picnic I would like to see just how many people believe as I do, that this crash had little to do with the Pilots, rather it was caused by a design flaw with the composite structure, weakened by the continual ingress of water into it because of the routes it operated.
Still we can't have all A300/A310s grounded, better to blame the Pilots.

So, am I to conclude from your comment that you believe the aileron and rudder control input and reversals, to the same maximum deflection as occured on this aircraft, if occuring on any other aircraft, would have been transparent and non-eventful?

I am not a structures expert by any stretch of anyone's imagination, and I know even less about composite structures; but, if your allegation has any merit, wouldn't it be true that other, similarly constructed aircraft, subjected to similar routes with similar frequencies, would be found to have the same type of structural weakening you describe?

Originally Posted by airsupport

IF that is what they mean, why don't they say that.
I guess because they want to make the report as ambiguous as possible, and aid in the cover up of the facts.

As typical of such report, this one contains “factual statements.” My experience with NTSB accident reports are that they don’t go into overly lengthy explanations when a detailed and scientific concept is being used in the analysis – presuming that those who are interested either know the scientific and engineering concepts involved or will research on their own so as to be able to understand the rationale behind their conclusions.

I guess I just have a problem with those who continue to deny observable, incontrovertible facts … facts that are evident to anyone … in preference for a belief that professionals, with no personal or professional motivation, are attempting to “cover up” a sinister problem that, were it to exist, is likely to raise it’s ugly head again in the future and cost additional lives and untold damage.

[Few Cloudy]

Rudders and training

Sorry to hark back to the dark ages but when I trained on the Victor K1 (one of the first big 4 jets for our American colleagues) which was very sweptback with its sickle shaped wing, we had two yaw dampers - hydraulic and electric - one as a backup. The Victor at altitude was very easy to overcontrol, in all axes and steep turns for instance could be a nightmare for a new pilot.

During training the two YDs were often selected Off and a demo Dutch roll was allowed to develop. We than had to stop it but Never with the rudder! You waited until the wings went through the horizontal and then put in an opposite aileron input to the direction of roll. On the roll back you did the same again and after about three oscillations she was under control. Of course some people did try to use the rudder because it was after all the Yaw damper which had been switched Off and those people got into great big problems - far from damping out the oscillation. they aggravated it because the rudder was far too powerful a control for a human to make the tiny and timely corrections required, as the YD did.

Later in life (sorry for the history lesson) I did some maintenance test fliying which involved stalling the aircraft (MD-80). This was about the only time I have used the rudder in flight and that was if one wing stalled before the other, causing a wing drop. Out of roll aileron has the effect of increasing the AA on the dropping wing, so it stalls even more. The way out is a very careful single gentle application of rudder to engender a secondary effect of roll, at the same time getting on with the stall recovery ASAP.

Now you can´t compare that to rudder reversals and we were of course at a very low IAS but even there that barn door was hugely powerful. It needs a lot of respect and that message needs to be got over to each new generation of trainers and students.

It aint a Pitts.

[airsupport]

So, am I to conclude from your comment that you believe the aileron and rudder control input and reversals, to the same maximum deflection as occured on this aircraft, if occuring on any other aircraft, would have been transparent and non-eventful?

I am not a structures expert by any stretch of anyone's imagination, and I know even less about composite structures; but, if your allegation has any merit, wouldn't it be true that other, similarly constructed aircraft, subjected to similar routes with similar frequencies, would be found to have the same type of structural weakening you describe?

PLEASE do NOT make your own conclusions based on what I said, however to answer your 2 questions, question #1, IF by "any other aircraft" you mean other than an A300/A310 then yes, this problem is only on them, not even other Airbus models. Question #2 is a little harder because of the way you asked it, there is NO "similarly constructed aircraft", this problem is unique to the A300/A310, and yes the routes seemed to play a part in it.

I can only speak of what was happening around the time of this tragic accident, hopefully Airbus have modified the aircraft by now, I really don't know as I am no longer involved with the A300/A310.

At the time of this accident I do KNOW that there was nothing more than a brief visual external inspection of the tail carried out on in service A300/A310s, and that on A300/A310s operating out of JFK and down through the Caribbean there was always this massive amount of water trapped in the tail, which obviously used to freeze and thaw on each flight until it was eventually drained during a maintenance check.

Hopefully both of these things are now improved.

[AirRabbit]

Originally Posted by airsupport

...however to answer your 2 questions, question #1, IF by "any other aircraft" you mean other than an A300/A310 then yes, this problem is only on them, not even other Airbus models.

Well, if you can provide anyone with some expertise in aircraft structures who will agree with you that the same aileron and rudder inputs (maximum deflection and maximum reversals, both rudder and aileron -- I think there were 7 of them in 9 seconds -- at the same or similar airspeeds) would be totally transparent and non-eventful on "any other aircraft, not even other Airbus models," I'll back away.

[airsupport]

Originally Posted by AirRabbit

Well, if you can provide anyone with some expertise in aircraft structures who will agree with you that the same aileron and rudder inputs (maximum deflection and maximum reversals, both rudder and aileron -- I think there were 7 of them in 9 seconds -- at the same or similar airspeeds) would be totally transparent and non-eventful on "any other aircraft, not even other Airbus models," I'll back away.

I really couldn't care less whether you back away or not.

Just PLEASE stop twisting what I say.

I am NOT talking about how to fly or not fly the A300, and I am certainly NOT accusing anyone of anything (that should please Danny), however after being based at JFK NY with an Airbus A300 operating throughout the Caribbean, and seeing this lack of anything but a token external visual inspection of the composite tail, and this water that was always trapped in the tail for weeks on end, I just cannot help thinking that these could have been factors in this tragic accident.

The exact type of composite tail on the A300s in question is unique to ONLY the A300/A310.

Also, as I said, I am sure Airbus now have a better inspection schedule and have fixed the drainage problem.

[AirRabbit]

Originally Posted by airsupport

I really couldn't care less whether you back away or not.
Just PLEASE stop twisting what I say.
I am NOT talking about how to fly or not fly the A300, and I am certainly NOT accusing anyone of anything (that should please Danny), however after being based at JFK NY with an Airbus A300 operating throughout the Caribbean, and seeing this lack of anything but a token external visual inspection of the composite tail, and this water that was always trapped in the tail for weeks on end, I just cannot help thinking that these could have been factors in this tragic accident.
The exact type of composite tail on the A300s in question is unique to ONLY the A300/A310.
Also, as I said, I am sure Airbus now have a better inspection schedule and have fixed the drainage problem.

OK, friend; don't hyperventilate; I have no interest in “twisting” anything – particularly what you have to say. I thought that when you said, “this crash had little to do with the pilots,” you meant that the pilots had little to do with the crash. I was merely reading what was posted. If you are not talking about how to fly or not fly an Airbus A-300, then apparently you and I are talking two different problems. OK, fine. I know nothing about the water drainage issues on the subject aircraft. Perhaps this was a situation peculiar to the A-300/A-310 aircraft – and I certainly have no problem in yielding to your familiarity with those circumstances.

My comment was strictly related to the cockpit control inputs made during the last few seconds of the FDR recordings of AA587. As I said, the cockpit control inputs recorded on the FDR would have done serious damage to any aircraft – regardless of what the structure was – composites, weakened composites, aluminum, stainless steel, or wet cardboard – and that is all I was saying.

[411A]

Many newer pilots to jet transport airline flying...

...may well have never been even remotely aware of the consequences of using the powered rudder aggresively at higher speeds.
They positively know NOW.
Was the concerned pilot in error?
Most certainly.
But, even more importantly, so was the concerned aircarrier, American Airlines (aka, the Sky Gods) for developing an advanced maneuvering program involving abrubt full rudder movements at high(er) speeds, and the FAA inspectors for approving it.
Abrupt full rudder movements repeated at high speeds are absolutely to be avoided, least you want to have an even longer career flying heavy jet transports.
The older guys were taught...now clearly, the younger guys now know, especially at AA.

[AirRabbit]

Originally Posted by 411A

...may well have never been even remotely aware of the consequences of using the powered rudder aggresively at higher speeds.
They positively know NOW.
Was the concerned pilot in error?
Most certainly.
But, even more importantly, so was the concerned aircarrier, American Airlines (aka, the Sky Gods) for developing an advanced maneuvering program involving abrubt full rudder movements at high(er) speeds, and the FAA inspectors for approving it.
Abrupt full rudder movements repeated at high speeds are absolutely to be avoided, least you want to have an even longer career flying heavy jet transports.
The older guys were taught...now clearly, the younger guys now know, especially at AA.

Well, what you allege here is not accurate. If you look at the AA "Advanced Maneuver Training" package you will find that references to the use of the rudder never advocate alternating rudder input and always reflect the premise that rudder inputs should be smooth and coordinated; never do they call for “abrupt full rudder movement,” particularly at high airspeeds. So, other than the fact that they DO discuss the use of rudder in this program (and the rudder is an important and an effective aerodynamic control fixture), on the surface, at least, there would be no real reason to be critical of the program as written. That being said, what would you condemn about the FAA review and approval of such a program? On the other hand, and where only AA instructor and line pilot personnel are truly knowledgeable, the question clearly becomes, “what are the pilots trained to do when actually alone in the simulator?”

On the other side of the coin, there are major airline training programs that advocate the use of aileron only as the initial control input (in response to the yaw-induced roll) when experiencing an asymmetrical thrust situation; i.e., an engine failure on takeoff. In one program at least, while not in the text of the program, it is explicitly discussed in flight training that use of the rudder should be delayed, and the application of rudder should be made toward the “down side” of the control wheel (to ensure the correct rudder is applied), and to use only enough rudder to allow the wheel to “center.” Clearly, this is taking an extreme opposite position on the use of rudder controls – and in the mind of many – is still not addressing the reason that a rudder is on an airplane in the first place … that being to maintain coordinated flight.

[Rainboe]

I'm interested in why these rudder reversals took place, and what caused this pilot to think this was a valid way of controlling the aeroplane in a violent wake encounter. I think most pilots would 'let it ride' the immediate drama knowing it would only last a few seconds, and then take gentle corrective action afterwards to restore normal flight. I cannot imagine what he was doing thinking you can make large rudder inputs, then reverse them an instant later, then reverse again. It seems to be using a sledgehammer control input, because a wide bodied Airbus doesn't encounter such variable external influences at that rate- not at that rate where it can be identified what is happening and what corrective action should be taken. It is a flying technique that doesn't belong on anything bigger than a Pitts- it is most certainly no way to handle a large aeroplane.
The whole accident comes down to either
-a fatal fin defect causing it to come off in flight, or
-a fatal flying technique by the pilot.
If it is going to be suggested the first is the case, it is inevitable that the pilot inputs should be examined, and this pilot technique is what causes so much disquiet. Pleading ignorance that such a technique may be disastrous is no excuse when the vast majority of pilots are apparently aware of the problems rapid rudder reversals can cause. How on earth can any pilot believe such a technique is viable, unless he believes he must forcibly bully the aeroplane to do exactly as he wishes? Water in the fin or not, there has been shown to be no fatal design flaw in Airbus fins, so it was operated outside design parameters. The flight recorder showed why the fin failed under overcontrol. So why did the pilot fly like this?

[Loose rivets]

As I monitor this thread, I still have an uneasy feeling about the chicken and egg logic of the argument. To quote myself.

How sure are they, that the FP's input was not increasing because of an already developing structural failure?
The feedback may have been so modified, that he was reaching further and further for a familiar response.

This still nags at my thinking on the subject.

[JustAnothrWindScreen]

Originally Posted by 411A

But, even more importantly, so was the concerned aircarrier, American Airlines (aka, the Sky Gods) for developing an advanced maneuvering program involving abrubt full rudder movements at high(er) speeds, and the FAA inspectors for approving it.
Abrupt full rudder movements repeated at high speeds are absolutely to be avoided, least you want to have an even longer career flying heavy jet transports.

Seems like someone touched a nerve here. Please tell me where American Airlines training program used abrubt (sic) full rudder movements at high(er) speeds and what department of the FAA approved this section that I cannot find? I have looked for that section but still have not found it. Why such venom?

[JustAnothrWindScreen]

Originally Posted by AirRabbit

Without trying to be overly critical of your opinion, I think that all of us would like to believe our own “press:” Supermen (and women), highly trained, laser-like mind, inerrantly finding the problem and whipping out a weird, but effective, solution. Would that it were so … but James Bond is still a fictional character.

I guess we will have to agree to disagree. "In my opinion" anyone that has flown high performance aircraft or have also flown captain on any of numerous commercial airliners do find that 9 seconds is a huge amount of time. Supermen, laser-like mind, whipping our a weird, but effective, solution, James Bond.... no not really, just a professional doing what they were trained and paid to do.

[DozyWannabe]

Originally Posted by Loose rivets

As I monitor this thread, I still have an uneasy feeling about the chicken and egg logic of the argument. To quote myself.

How sure are they, that the FP's input was not increasing because of an already developing structural failure?
The feedback may have been so modified, that he was reaching further and further for a familiar response.

This still nags at my thinking on the subject.

Because according to the NTSB's scan of the fracture surface of the recovered section of the tail and attaching lugs, there was no pre-existing evidence of fatigue, and the only stress area was at the main point of failure. The loads engendered by the FO's control inputs were capable of making even an unfatigued tail snap because the 'Ultimate' design load was exceeded.

If the tail was suffering from dangerous levels of disbonding and or fatigue then it would have failed well before the point at which it did.

[AirRabbit]

Salient questions are raised by Rainboe and Loose rivets.

Originally Posted by Rainboe

I'm interested in why these rudder reversals took place, and what caused this pilot to think this was a valid way of controlling the aeroplane in a violent wake encounter. The whole accident comes down to either
-a fatal fin defect causing it to come off in flight, or
-a fatal flying technique by the pilot.
The flight recorder showed why the fin failed under overcontrol. So why did the pilot fly like this?

I think to have a better understanding one would have to go back further into the F/O’s flying career. There is that one suspicious account when flying the B-727 where both the Captain and the F/E remember him being quick to use massive rudder applications in an attempt to either maintain or, perhaps, from his perception, regain, control of the aircraft after having encountered wake turbulence. Determining why this particular incident was not followed might be an interesting effort – but perhaps the Captain and F/E believed the issue was isolated and had been properly addressed. I would wonder if any instructor or check airman ever noticed similar tendencies from this young man. It would be interesting to find out from the instructor who administered the AA Advanced Maneuver Training to this F/O if he demonstrated any tendency to “over control” the rudder during that training.

Originally Posted by Loose rivets

As I monitor this thread, I still have an uneasy feeling about the chicken and egg logic of the argument. To quote myself.

How sure are they, that the FP's input was not increasing because of an already developing structural failure? The feedback may have been so modified, that he was reaching further and further for a familiar response.

This still nags at my thinking on the subject.

Of course one would have to acquire the services of a more experienced FDR reviewer than me, but from the animation of the FDR recordings, it is relatively clear that after the first several rudder applications the airplane was responding as it should – given the fact that the applications were full throw – and then reversed. The airplane was responding to the pilot’s inputs in all three axes – at least up to the time when the data feed ceases. I would think that any developing structural failure would have been noticed in either the airplane failing to respond to control input, OR it would have been responding to vertical fin/rudder displacements that were not called for by the pilot. However, neither of these situations is evident in the data available.
http://www.ntsb.gov/Events/2001/AA58...path_web01.wmv

[barit1]

Forgive please if this is old news, but the initial releases of the CVR transcript included two episodes of a "rattling noise". Have these been sorted out?

[AirRabbit]

Originally Posted by JustAnothrWindScreen

I guess we will have to agree to disagree. "In my opinion" anyone that has flown high performance aircraft or have also flown captain on any of numerous commercial airliners do find that 9 seconds is a huge amount of time. Supermen, laser-like mind, whipping our a weird, but effective, solution, James Bond.... no not really, just a professional doing what they were trained and paid to do.

Well, yes and no; and I certainly don’t mean to “step” on your opinion – you certainly have a right to disagree with mine.

Nine seconds certainly can be a huge amount of time – but, I believe it all depends on what happens during that time period. I would submit that when a 9-second window is divided into segments, where the first third of it is used to adequately address the issue at hand or, more properly, believe that the issue had been adequately addressed; taking another third of that window to verify that belief – that being the Captain’s query, “You alright?” and the confirmation from the F/O, “Yeah. I’m fine”; the balance of that window, at most a third, or 3 seconds, comes down to processing the “I’m fine” response while having the airplane’s tail ripped off. Again, I don’t think either of these two pilots were watching a series of controlled events unfolding very slowly and deliberately before their eyes.

Yesterday, I posted a quote from an accident report only to show that there ARE times when what would seem to be “adequate time,” for some reason, is not. In that accident, a Check Airman, serving as PIC, was assigned to a line flight to specifically observe a F/O for proficiency, and during a crosswind approach to landing where the F/O apparently showed signs of not coping well with the progress of the approach, allowed the F/O to establish a high rate of descent while still crabbed on the approach, failed to notice that the F/O did not maintain adequate control inputs for the situation, failed to take control of the aircraft when the F/O did not flare the airplane at the appropriate point, and allowed the airplane to land so hard that it collapsed the right MLG, dropping the wing to the ground, dragging the airplane off the runway. The report cited the improper crosswind and flare techniques by the F/O and the Captain’s failure to take corrective actions.

Where a case could easily be made on this landing accident that the Captain had every reason to believe the proficiency of the F/O may have been in doubt and, somehow, got caught either over thinking the problem or was over confident in his recovery abilities, I think exactly the opposite case can be made for the Captain of AA587. The AA587 Captain had no reason to be suspicious of his F/O’s proficiency. He observed the F/O successfully transition a wake turbulence encounter mere seconds beforehand. Whether or not the Captain had any idea of the magnitude of the cockpit control deflections the F/O used, we’ll probably never know, but as the situation didn’t resolve itself as quickly as the first wake turbulence encounter, he queried the F/O about how he was doing and was told “Yeah, I’m fine.” It was THEN that the fit-hit-the-shan!

[airsupport]

As I monitor this thread, I still have an uneasy feeling about the chicken and egg logic of the argument. To quote myself.


Quote:
How sure are they, that the FP's input was not increasing because of an already developing structural failure?
The feedback may have been so modified, that he was reaching further and further for a familiar response.

This still nags at my thinking on the subject.

Exactly my theory, which will also be discussed at the picnic.

[bubbers44]

Wish I could be at the picnic. Did the A300 really have rudder inputs from the pedals like it showed in the video or did they just use rudder actuator inputs to the FDR to show what the rudder pedals would do to make the rudder move? My friend who had the uncommanded rudder movements didn't move his rudders and the yaw damper was throwing his airbus out of control trying to land in Miami. Does the Airbus really have rudder pedal movement in their FDR. Years ago I heard no. I just remember that TWA 800 video that showed them zooming up 1000 feet after the explosion and the nose falling off and lost confidence in their credibility of video reinactments. I dought that this video was accurate either. Feeling your captains seat being thrown around violently would cause any captain to fix it and say I've got it and take control if the FO was out of control. I think Sten was trying to fix a problem, not cause one. Wake turbulence is a non event, we encounter it every month or so. Has anyone experienced what it feels like to have a tail failing in flight? Probably a lot of fluttering and yawing.

[JustAnothrWindScreen]

Originally Posted by AirRabbit

I would submit that when a 9-second window is divided into segments, where the first third of it is used to adequately address the issue at hand or, more properly, believe that the issue had been adequately addressed; taking another third of that window to verify that belief – that being the Captain’s query, “You alright?” and the confirmation from the F/O, “Yeah. I’m fine”; the balance of that window, at most a third, or 3 seconds, comes down to processing the “I’m fine” response while having the airplane’s tail ripped off.

I have never personally reacted in the way you describe. Having said that, everyone does react in a different manner. Your description reminds me more of a monday morning lawyer trying to prove a point whether that is how things actually took place or not. Like I said earlier, we can agree to disagree.