JenCluse

via 'Layer 8', a few days ago:

"(United States) Air Force wants studies impact of human reliance on autonomous systems

at http://www.networkworld.com/community/blog/air-force-wants-understand-impact-automated-s"

I wonder how long the planning for the study has been in place?

Please resume normal conjecturing.

worried SLF

Hi all! I don't understand why everyone seems to ignore that even the conversation between two pilots ever since the start of the event didn't resemble a conversation between pofessional pilots? No call outs, no attempt to analyse the situation professionally, no checklists mentioned, no procedures. How badly were they trained exactly and how average were they? I find it frustrating that so many people seem to be reluctant to accept that what was found so far was more than enough to bring down the plane. Two FOs that couldn't fly complemented by a capitain that couldn't command put in one cockpit and as a result an event of frozen pitot probes that is not terminal by nature developed into a catastrophe. 228 dead. What is so surprising that other factors are needed? That modern planes still require pilots to know how to fly? After all, that's what happened. Pitot froze, obscure UAS procedures - this is on the surface, but if you scratch it, it's the case of A/P disconnect and the pilot's inability to fly the plane - as shocking as it sounds. Add unfamiliarity with plane's features. Multiply by two, add the capitain who failed to take responsibility, command and control when called to interfere (it's academic that it might have been too late by then). 228 dead. And insistance on an aviation forum that modifications to the plane are due to prevent this. I am a lay person, but I understand that a pilot without flying skills and solid knowledge base is a dead man walking, 100% at the mercy of the plane (automation) and his colleagues and a liability in some situations. And this is what happened. No addditional causes are needed.

Why there is insistance that the "plane did something" or that it caused the crew to do what they did? How can anyone take seriously AF's bull**** about "complexity of man-machine interface" after the converstaion in this cockpit was revealed and the latest report published? There is no and shouldn't be any interface in any sophisticated technology equipment that allows unproficiency. What's next then? Kids-friendly nuclear power stations? Interface didn't play any role in the event and for this crew any different interface could be just another thing not to know. To believe otherwise one would have to ignore all that was said and also what wasn't said in this cockpit. We have pilots that demonstrated that they knew and understood their plane - the one they were working on - badly. There is no reason to conclude logically that if plane was designed differently they would have known and understood it any better. They ignores stall alarm for almost a minute without saying a single word about it and then it was stopped by design, it's a pure conjecture to say that if design was different they wouldn't ignore it.


I disagree with recurring theme "something must have been wrong with the plane even if the investigation doesn't say it". In the light of what is published so far I don't understand where this conviction comes from. I saw failures on many levels but they are not technology-related. Does anyone blame technology when using it without reading the manual and breaking it? If you have a piece of equipment but only ever know one button there will be problems. And IMHO any debate about technology in the context of this crash will mean that these failures won't be properly addressed. It is clear that advances in technology no matter how big don't mean that professionals skills can be allowed to deteriorate especially when they are meant to complement and in times to compensate for this technology. Not a rocket science to understand. However I will agree that debate is due on why this is still allowed to happen. And please lets not try to make plane manufacturers responsible for pilots skills. Maybe instead airlines should be made to EARN their share of profits and prevented from attempting to take a free-ride on the back of manufacturers by manning new planes with untrained crews? Free-riding is unfair competition, and because as the result of poor training events like frozen pitot are turned into fatal, this is also a murder.

Machinbird

BOAC,
Been there, avoided the temptation to pull right back. Still here to pester you.

It may not just be ground proximity that triggers the pull reflex. Think about some of the accidents you know where the guy flying pulled the wings off.

Were they all at low level? Doesn't "when bank angles exceed their comfort levels" factor in?

jcjeant

Hi,

Methink .. the best training (for pilots) for self control will be a training for deep scuba diving
There .. 1 second of panic = immediate dead

CONF iture

Thanks a lot for the document mm43.

In paralele to the outer ailerons inaction, another point of interest :
This is in page 126 and relates to Alternate Law.
If I get it right, the THS should NOT have moved ... but it did !?
What was happening in that aircraft ?
This reminds me the WRG fault message ... only Svarin was interested to discuss.

ChristiaanJ

I was interested as well, but the discussion petered out through lack of useable data.

Hamburt Spinkleman

You get it wrong. In ALT2 with loss of 2 or more ADRs low speed stability is lost.

You should have continued readin thru page 127.

DozyWannabe

@Hamburt Spinkleman:

Correct - the important paragraph is on the following page:

There's a reason that Alternate 2 is marked with a very clear "(NO PROT)" on the ECAM.

CONF iture

Hamburt,

My point of interest here is NOT the low speed stability or the roll control ... but the autotrim.
I think the autotrim activated as it did not have to.

Now, if it's normal by conception to autotrim under stall warning, it is aberration.

mm43

CONF iture; ChristiaanJ;

I raised the THS auto trim matter by PM with another poster a couple of days ago, and for the benefit of all, the excerpt from the A330 Instructor Support Manual follows:-

The ALTN 2 provision clearly indicates that the longitudinal static stability cannot be "automatically" restored.

DozyWannabe

This is a serious question, I promise I'm not being facetious here... Why do you consider it an aberration?

Would you not use manual trim in a conventional aircraft if elevator authority was not enough to help you escape the stall, or indeed if the elevators jammed? Autotrim is simply a way of providing trim function through the sidestick, and in the Alternate Laws the pilot has full trim authority through the sidestick. Alternate 2 removes some or all of the soft protections (soft meaning that sidestick input can override them, so in this case there would have been negligible difference had Alternate 1 latched, because the PF did not let go of the stick throughout the sequence).

The very reason for the existence of Alternate 2 is because with certain sets of failures, the FCU is programmed to recognise that it cannot manage the flight, and so full authority is given to the pilot. This is entirely in keeping with the Airbus engineering philosophy, which acknowledges that the last line of defence is the pilot, but could potentially cause problems in an operational sense if the airline concerned has used the existence of the FCU protections in approximately 99.9 (rec) of flight time to under-train pilots in manual handling.

In terms of systems architecture, Stall Warning is part of the notification subsystem and is not connected to the FCU protections in any way. The purpose of the notification subsystem is to tell the pilot, who in Alternate Law has full authority, if the aircraft is in a non-normal/dangerous state. The design relies on the pilot to heed that warning and take appropriate corrective action, as is the case in any other airliner. The notification and protection systems are complementary rather than co-operative or consequential - if the protection systems are functioning then the severe notification logic (e.g. overspeed warning, stall warning) should sound either briefly while the protections compensate, or not at all.

One of the fundamental misunderstood perceptions of the Airbus (and I suspect Boeing) FBW systems is that they are seen as a monolithic system in which everything is tied together - they are not. FMS/AP is distinct from FCU is distinct from reporting systems - they interoperate, but they do not form a cohesive whole from an engineering standpoint - nor should they lest they risk creating single points of failure. The protections are part of the FCU architecture, and the reporting systems are part of the avionics.

The design of the FCU states that absent specific parameters (in this case ADR data), then the pilot should have full authority - the safe limits will be notified via the reporting subsystem to which the pilot is expected to respond in a timely and correct manner, just as has always been the case before the days of FBW and the FCU system.

I don't see anything inherently wrong in retaining autotrim in Alternate Law, but the ramifications of retaining it must be trained for and understood.

Lyman

Doze,

THS: It was not retained, it resumed, having stopped at ALT LAW2 Latch.

You gonna leave your post as is?

RetiredF4

mm43

we had this discussion in thread 3 ages ago. I think it was TAKATA who explained it there.

The stopping of the THS trim is a function of the static longitudonal stability protection and is only available in Alt1, not available in ALT2.

In certain failures like 2 ADR which was the case with AF447, the longitudonal static stability cannot be restored, which means imho that THS trim remains available.

I would be cautious with the reference anyway, the instructor support manual is from 2001 and has been replaced by the FCTM some years ago. In the FCTM the wording is similar, but the part with the trim is missing. That is for the A320 as well as the A330 /340 family.

Also the Technical Training manual states, that in ALT2 only Load factor protection would be available.

mm43

RetiredF4;

I actually agree with you!

The ALT2 proviso "kills" further discussion on it.

HazelNuts39

This is what BEA #3 (p.41) says about it:

Coagie

worried SLF: Because it's unbelievible that none of the three pilots knew what they were doing. Admitting that these three were incompetent is difficult, because their incompetence tarnishes a historically heroic profession. Air France would have been better served by actors. At least the CVR would have sounded like professional pilots. Now Air France has no place to hide. Maybe some of the other carriers will learn, and if they don't hire competent pilots, they might, at least, try to train them to be competent pilots.

DozyWannabe

@Lyman - just this once I'll respond. You show me where it stops and resumes, and then I'll contemplate taking you seriously, otherwise I assure you that trying to engage me further will remain an exercise in futility.

mm43

@Dozy;

Think you'll find that Lyman will leave it alone.

Have been back and highlighted the ALT-2 proviso in the graphic a few posts back. As HN39 has carefully pointed out, the BEA have had Airbus prove the aircraft behaved as expected.

Mr Optimistic

Is Interim Report#3 still available at the link in the first post ? Tried to download it but no luck. Looking for extracts of the conversation to see the extent of cross communication of SS actions. May be one thing to not see what was happening, surely not deaf as well.

DozyWannabe

@Mr. Optimistic:

Both links (FR and EN) working fine for me. PM me if you have further issues and I'll send you my local copies.