maybe you are confusing this with mechanical back-up? fd.

It wasn't mechanical backup = complete loss of electrical power
On the other hand, AOA was constantly above 30 deg.

48° AoA is massive. Many test pilots have never been there. No modern Jet transport has ever been there in a controlled and monitored environment, so absolutely no data is available.
It is very questionable whether there were any "correct responses" in that situation. I also tend to believe that this was it, once they got there.

Not so. The stall warning can be generated in normal law, but the idea is that NL should prevent you from getting to a point where you need it.

Sufficiently violent windshear has triggered the stall warning in the past on A320 series but the difference is that the aircraft is already applying full down elevator input as it occurs and will recover from the stall itself.

Why? The Airbus cannot enter deep-stall like some of the 1960s high tail designs. With the controls centralised and throttles cut, surely it would eventually pitch nose down like any other aircraft?

An overlay display could show both sidestick inputs.

Such a purely informational display would not require any programming mods to the existing active controls setup, but would still allow pilots to deconflict their inputs.

Edmund

Macro CRM
 

A number of excellent posts here today. Thanks. Real pleasure reading them.

Having been involved in, and following, discussions like these for many years now, it is clear to me that on some points we have to break an industry deadlock in order to get safety yet another notch up. The low hanging fruit has already been properly picked.

Let’s take 2 important points. I hope you will not find them ‘philosophical’, as they are literally deadly serious. You will see them back in errors and incidents and accidents,even when their direct relationship to ‘visible’ events is not immediately clear (not only in operations but for example also in program management,engineering and manufacturing).

The first point concerns national and company cultures. French and US cultures are different (French culture differs from other European cultures too by the way). As a consequence of that, each will deliver products and solutions that have some inherent weaknesses. Sometimes you see this inside the industry – when you move work from one country to another for example they pop up sooner or later.Sometimes you see them in incidents and accidents.

n For example (mods - not judging, just illustrating – you can say similar things about other manufacturers) - Boeing has and will have some manufacturing issues for example that you will not quickly see in Airbusses.

n For example (mods – again, not judging, just illustrating) - Airbus has some design choices and issues for example that you will not quickly see in a Boeing. In some cases Boeing has followed the Airbus choices (delayed by X years) but made different design implementation decisions. In one case I am constantly checking if Boeing cultural manufacturing issues will come out of that by the way (hope it will be in incidents rather than accidents).

The second point is communication. I have an idea about what Airbus is going to say lateron (“when they have had time to study the report” – which is an interesting statement by itself). I also have an idea about the reactions that they will generate (rational,emotional, frustration, ...). And see some of these Airbus statements bouncing of a proverbial wall rather than being really absorbed and commented upon by some recipients. Clear and explicit examples of this bouncing can be found in the KNKT AirAsia Report which includes statements directly taken from AirAsia manuals. Statements that are counter to what Airbus has stated over many years by now. There are of course also Boeing examples. Citing one example - a famous US aerodynamics specialist called it the “NIH Syndrome”.

Both culture and communication together have been root causes of very serious issues that both Airbus and Boeing have had with major new programs over the last 15 years or so.These are not played out in accidents but in significant program delays and cost overruns. They have had and may have some issues later.

You might say that together both point to a requirement for CRM on an industry level and scale, Macro CRM.

Disclaimer - I don't fly and haven't flown the bus.

However, abnormal attitude law does seem to be a big issue in general to me. As I understand it, bus drivers only ever touch the trim wheel to set trim for takeoff.

Therefore a law that:

- (after an upset has occurred!) freezes the trim in a position that may have contributed to the initial upset

- expects pilots in an upset to recognise and comprehend this law degradation

- expects pilots to trim manually to assist recovery, despite never trimming manually in normal ops

In my opinion has serious issues. In general, the concept of being trained out of the need to trim is in my view inherently detrimental to the skills required for upset recovery.

A common comment in this and the AF thread is: 'Why didn't they react to the STALL warnings?' The most likely answer is that the aural warnings were being sub-consciously filtered. When the brain is overloaded, the first sense our brains typically 'load-shed' is hearing. I can imagine that the pilots in both accidents would have have been very over-loaded trying to figure out what was happening and so their brains were not processing any aural information at all. This could also explain why the F/O didn't let go of his controller, rather than being a language problem, it might have been a 'I'm not hearing anything because my brain is over-loaded' problem.

Jwscud in Alternate Law, pitch is the same as in Normal Law. I think you are referring to Direct Law which is not appropriate to this discussion!

In the event of excessive pitch up (possible in direct law of the A320 ) I remember being taught forty years to immediately roll the aircraft beyond 90 degrees to give one a chance to sort the problem out.

mcdude: Probably not, rather the Abnormal Attitude Law. As did _Phoenix, which I initially missed.

http://i65.tinypic.com/o6z4fp.jpg

Re auto trim in Alternate Law; some confusion?

If Abnormal Attitude Law (*) is triggered by an upset, Pitch, Roll, etc, as defined on page 79 of the report (#3570) then auto trim is frozen at the value existing at change over.
* This is Pitch Alternate with load factor protection, but without auto trim (#3574).
However, if the aircraft ‘recovers’ from the upset condition (Abnormal Attitude no longer valid, but note overriding AoA range, and that the aircraft could still be in a stalled condition), then the auto trim might be available.

The description of system behaviour in #3574 indicates that auto trim is recovered after the ‘condition’ (presumed to be the upset condition) is exited, but is unclear (and probably irrelevant in this instance if Normal Law would be reinstated) which law, Alternate or Attitude is retained.

In this accident would a power interruption as suggested in the report trigger Alternate Law with auto trim?
Or alternatively, and /or during the event after power interrupt, would the Abnormal Attitude Law be triggered
and if so, which ‘law’ has priority, i.e. could a power interrupt inhibit a subsequent tigger point?
And could auto trim be reinstated later in the event, yet still in Alternate Law?

Systemic (not necessarily systematic) issues
 

A0283 raises large issues, within a context of what I think it would be accurate to refer to as the overall system of international civil aviation (post w/title "Macro CRM"). While studiously avoiding any of the "flying" issues presented by the report's contents and also (if an understanding of some of the thread criticizing the report is correct) by the accident itself, my premise is that, it appears very nearly certain that efforts to address the underlying problems which caused this accident are not working, and have essentially no chance of working. By "working," I mean "solving the problems and preventing the same or essentially same thing from happening again."

But adding in the larger, "Macro CRM" issues A0283 identifies, is there an urgency brewing? - a need for mobilization of the overall system? Why would this be so? Here:

Indeed, ICAO's baseline projections are that overall global air traffic will double within something like the next 12-15 years.

The point I am hoping to make is, where does the learning curve go, next? After AF447, the learning curve seems not to have moved far enough (or, if it did move, it has not kept up with the scope of the problem). Where is the kick in the ar$e to the system going to come from? (And while observations about the profit motive, pin-headed management of some air carriers, wide variability of compliance with SARPs among various regions and countries, all are valid, they're kind of beside the point, is it not so? Those restraints on progress are well-known and not going away - the point is, how to improvise, adapt and overcome them? Unless you want to disbelieve that a winner never quits and a quitter never wins.)

To build in a mechanical connection between the two sidesticks would remove one dimension of complexity. And complexity is what get you by the balls if fear is in the air.

New Gulfstream G500/600 aircraft will have linked Active Sidestick technology. Each pilot will be able to see and feel what the other pilot is doing (or even what the AP is commanding).

It's a no-brainer evolution.

I agree, again like in AF 447 it looks like none did recognize the stall situation, at least not in the first vital minute. Imho there is a reason I mentioned in the AF447 thread before. In training only stall approaches and the recovery from those are practiced, not a developped stall. The Nz felt (or simulated in the box) during such a training exercise is 1, transitioning to a bit less than 1 when the descent rate due to stall starts, where recovery is initiated by pushing the nose down. In case where the recovery is started later, the box will neither simulate the true stall behaviur nor the continuous reduced Nz value.

The below 1 reduced Nz is accordingly asociated with the end of the stalled situation and the point where soon after the recovery to level flight starts. If we could check the Nz graph (i could not find it in the report, but forgive me if it is there and I just oferlooked it) we would see similar Nz value like in AF447, the Nz value below 1 ( I gestimate around .7-.9) for a prolonged period of the stalled descent. Such values can be felt very well. They may be even very uncomfortable if they have never been encountered before. Stalls on the other hand are thought to be accompanied by some violent maneuvering of the aircraft asociated with positive Nz. Reduced Nz could therefore be asociated with a unstalled situation.

What is my point? If the flight behaviour prior stall has been missed as being prone for an impending stall, the entry into stall and the following developped stall might be missed completely due to the unspectacular entry, and the felt Nz below 1 could be interpreted as the normalisation of the situation. We know that it is wrong to go after the body sensation, but in a stress situation it will happen anyway.

The most important point for the prevention of a stall and for a necessary stall recovery is the early recognition, that the flight before the stall entry is critical and a stall may occur. Then the crew is prepared for the flight dynamics which could developp during stall entry and also during a developped stall and how ro counter those. The importance lies in the avoidance of such situations.

It is a training issue, imho still not adressed thoroughly enough.

RetiredF4,
So, we are back to the AoA indicator. It should flash red and honk!

Hell, even the Wright Flyer had an AOA indicator.

Even Santa has one - fitted to Rudolph! ;)

So you're saying that the pilots who ignored a multitude of obvious indicators, would somehow magically look at the tiny AoA indicator in a high stress situation and all would be well? Especially considering the fact that 99.999 percent of the time they don't look at it (if it's available), hence, in a high load scenario, they would never do it anyway.

Most people, and the industry, seem to be missing some fundamental safety systems issues here by focussing on the detail rather than the big picture. A key concept of safety systems is there are three types of factors: human, machine, and environment. In this case environmental factors are largely the inherently unsafe position of a flying aircraft at altitude.

With respect to human factors, human error is simply an unavoidable element. Human error can be minimised, but it will never be eliminated. So while better training and higher levels of competency should be constant goals, they will never prevent human error being a causal element. Focussing on human error as the root cause, or fixable cause, in these incidents is a mistake.

With over 35 years of experience in incident response and investigation, systems design, and high-risk hazard and risk analysis expertise, it is absolutely obvious to me that there are design flaws in the airbus operating environment. In no other high risk industry would some of the human-machine interface elements, (discussed enough here that they don't need repeating) be allowed to continue in place following the incidents that have occurred.

It really is that simple. But I imagine the financial cost of remedy is immense.

bud,

Very well put. I think that Airbus management are secretly wishing that they had linked the sticks and possibly added force-feedback, but of course they can never say that.

Beyond the advantages of linked controls from an awareness of what the PF is doing, consider the following (from the article):

Imagine on 8501 (and AF447 for that matter), that in addition to triggering the stall warning the alpha limits triggered a stiff tactile resistance to continued back pressure on the sidestick. Would this have possibly cued them to quit yanking back on the stick?

Bud leon

Unfortunately you are missing the elephant in the room. The AIRCRAFT did not cause the accident incompetent pilots did.

One who could not fly straight and level and one who thought he knew better than Airbus and their test pilots. All they had to do was emergency cancel the warning and write it up on arrival!

If they had done that there would not be this ridiculous A vs B or stall recovery discussion.

The regulators and training are at fault, how many of the pilots in the cockpit these days have been scared and learnt from that experience? Flying is like being at sea the environment is rarely forgiving. Those that have completed training through a majority of simulator time certainly will not have.

I don't think he is. Some pilots can no longer fly. That's the elephant. More so on Airbus? Who knows? Can you tell what the other guy is doing with the stick? No. You can see the result, but...

Well put Iceman50.

where were the safety champions
 

Others share the responsibility, but at significant times the captain must rise to the occasion by all means at his disposal. Exactly when is that?

The answer is, whenever it is obvious that others are not.

I'm not referring to compliance with regulations or getting a good night's sleep before a long flight duty. The captain is compelled to do that and it is generally reasonable to assume that these type of things are not normally a problem.

I am referring to responsibility during stressful or unusual circumstances. It is an extraordinary circumstance when repetitive flight control malfunctions cause multiple taxi back or unreasonably divert attention in flight. Exactly like the situation that existed for months on this aircraft.

Apparently no pilot sufficiently pressured the company to fix this problem when it became more obvious. If this is so, the question is, "can pilots in this airline ever confirm their authority and take an increasingly appropriate share of the responsibility?"

There are also other fatal hull losses that could have been prevented but for the absence of pilot fortitude before departure.

Another classic will be MH17, downed by a BUK missile. It was already known that an AN-26 had been downed by a BUK in that area. When I heard that 3 days later a B777 had been shot down, I was amazed that MH17 would plan over Ukraine, since a BUK has a capability in excess of B777 max altitude.

Korean, Asiana, BA and some others avoided the area.

Aeroflot, Singapore, Lufthansa, and others, continued planning via Ukraine. What were these airlines and their captains thinking?

Where were MH17 safety champions? Same place as QZ8501, nowhere.

iceman, I get that. But in normal high risk, high technology, industrial safety systems unsafe human behaviour is significantly mitigated by technology. And I feel it is abundantly clear a number of elements in the airbus human-machine interface exacerbate loss of situational awareness and control. Those are design flaws and should not be left in there. You have to look the other way to reject the evidence.

So blame the pilots and not the flawed flight control system.

You adress the problem quite correct in both senses. A multitude of indications and warning informations could not get their focus directed on the real problem, a stall.

But a single instrument can tell the summary of those instruments with one glance, there is no need to check others. The AoA indicator sums up those informations in one indication by showing the AOA in real time. Well designed and placed it could be the attention getter. In such a situation the only information needed for recognition and redovery would be the AOA, attitude and speed, and those could be fed into the PFD replacing the normal indications for the critical time frame. Then the mentioned tiny AOA indicator could be placed somewhere as backup.

Those who have never used an AOA (even a tiny one) see a problem, the others see the improvement.

From the Wall Street Journal, December 3, 2015:

"Air Asia Crash Report Dropped Stronger Language Proposed by French

Indonesia’s report on the fatal crash didn’t include tougher statements from French expert"

Air Asia Crash Report Dropped Stronger Language Proposed by French - WSJ


The article was apparently referring to some of the BEA's comment in the Accredited Representative Comments section of the KNKT's official accident report.



From page 186 of the report:




As others in the thread have said and the BEA has said why is the complete CVR transcript not included in the official accident report?

Warning: heresy here
 

[Long time pprune watcher, ex-PPL SLF here]

Thought: Ignoring sidesticks vs control column, isn't an Airbus in Alternate Law just a Boeing minus the stick shaker and stick pusher?

Is it feasible, without contravening the First Law of Airbus ("uncoupled sidesticks are here to stay"), to provide (side)stick shaker and pusher in Alternate Law? Combined with a PFD simultaneously defaulting to the large, brightly-coloured AoA display mentioned earlier, this might get things moving in the right direction (well, until the FO heaves back on the stick again).

There has been extensive talk of aural and visual 'blindess' of crews when under pressure, isn't it time to consider this TACTILE assistance?

JS

I don't accept that an AOA would have been a safety enhancement. These guys already had task saturation and were unable to perceive the real problem despite the FWC's blaring "STALL STALL" at them all the way to the ground.

During AF 447 that warning stopped at least for a time, so in some respects their confusion despite remaining in the stall was understandable, however Air Asia had no such ambiguity, The FO held full back stick for the last three minutes of the flight and from this point on the captain, for whatever reason was unable to provide any useful assistance, notwithstanding some words that were best described as gibberish.

For the Indonesian authorities to point out that this was at least a flight training problem within the organisation is completely appropriate. If one of them were having a bad day but the other guy knew what to do that might be bad luck but neither of these guys were competent to be in a control seat and that has to speak to a significant organisational failure.

The AoA Indicator could surely improve aircraft safety, if it would be a primary instrument from the first flying lesson. It would be essential to understand that Stall is not an airspeed issue, and to use AoA to maintain a margin to stall. Unfortunalely on a typical SEP you can not install a reliable AoA indicator... So this discussion is pointless.

Unfortunately the typical aircraft design evolved from there, and the propeller mounted at the nose of the fuselage became the standard. So now we all rely on the Airspeed indicator, which fact is one of the must useless instruments we have. AoA and Ground Speed are the two parameters we need to know.
AoA tells you all you need to know about the aerodynamic situation you are in.
Ground speed is what you need to plan your further flight (arrival time etc.) and to navigate.
IAS is totally worthless, as you need several other paramters to really draw a valid conclusion from it.

There are improvements that can be made in every machine when new levels of human ineffectiveness are explored. But the "non-linked sidestick" seems to be of significant issue only to those who don't actually fly the Airbus.

• It might be a tiny bit better if it had interlinked sticks. Maybe. So long as new issues are not introduced - and I'd bet they would be. Dual independent electric gives a level of redundancy that everyone conveniently forgets.
• It might be a tiny bit better if it had moving t/l.
• It would be a bit better if the "dual input" and "stall stall" could live side by side with each other.

But none of that matters, when you have pilots who exist in a system where it is fine to pull CB's on a critical flight control system when in flight. Pilots whose training and experience leads to a Pavlovian response of pulling up in the face of undiagnosed adversity. Pilots whose communications are so bad that instructions like "pull down" are given.

To change the aircraft is to accept that the level of piloting is fine and that it's simply the machine that needs fixing. Never has there been an accident where this is so far from the truth. The machine was airworthy and safe, the pilots were not.

The fault lies in the training, standards and culture that the pilots were exposed to. I would bet that the same individuals with different training, standards and culture would have:

• Not caused the fault in the first place.
• Not over reacted to the yaw.
• Not flown a zoom climb all the way to a stall.
• If they had done the above, used SOPs to allow the more experienced pilot to assure control and fly a successful stall recovery (by simply lowering the nose).

If I want to see what the FO is doing with his sidestick (for example, while I am pressing the button during a baulked landing where I have taken control, or even just on a normal approach), I use my eyes. They still work quite well, and give a full picture not just of what inputs the FO is giving, but what his face looks like too - which cannot be replicated by any control column system that I used to operate.

This is all about training (and the cost of doing it properly).

Actually the Bus does provide AoA indication to the crew, as does any aircraft that displays PATH. It's the difference between PiITCH and PATH, both of which are staring you straight in the face.

Interestingly there was no mention of this in the most recent Airbus training movie related to stall awareness and recovery.

Admittedly the presentation doesn't display the AoA as a percentage or limit, and neither will it function if air data is compromised or lost entirely.

It beggars belief that space cannot be found on the panel (as it was on all biz jets until recently) for a simple, direct reading, non air data instrument, the like of which would clarify the situation as a last resort for a confused crew.

Further, when faced with erroneous air data I would argue that a direct reading AoA is an indispensable piece of equipment that should be mandated.

A QUESTION FOR AIRBUS PILOTS
 

This accident has highlighted, amongst other things, that when an issue arises where ALTERNATE LAW is use, the crew simply could not cope, with disastrous consequences.
Just how much time is spent in the simulator, once on line, practising these non normal states?
How frequently during normal line operations have drivers had to cope without NORMAL LAW in use.

If you don't keep in regular practice with the "OTHER LAWS", it is hardly surprising that it will prove to be a challenge, even for the more experience crews.

I suspect that this is such an infrequent event, it may well be a "one in a life time event" ?

For the avoidance of any doubt, I have never been AIRBUS rated.

Completely agree.
Aviate, Navigate, Comunicate.
Aviate = fly the wing. If you have trouble here, the other two won't solve the problem.

Planes have stalled and crashed since planes are flying. Many many times.

Among these are now also 2 recent instances where Airbus have stalled and crashed. To attribute these accidents to non-moving TL or to not-connected sidesticks is an absolute red herring.

Moving TL and connected yokes didn't prevent Amsterdam, nor did they prevent San Francisco. There is however reason beyond reasonable doubt that Amsterdam (thanks to mode selection integrated in the TL and autotrim) and San Francisco (thanks to alpha-floor) wouldn't have happened in an Airbus.

Our industriy continues to see weird accidents from a basic flying skill point of view. We seem to have many crew flying around the world airspaces who just do not have the basic skills necessary to actually hold a seat in a jetliner cockpit. This is not a problem of these pilots, but of the environment which lets pilots without the necessary training into the cockpit.

This is a problem of the regulators and the manufacturers training departments (in the sense of how they setup their type ratings).