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-   -   CRJ down in Sweden (https://www.pprune.org/rumours-news/572882-crj-down-sweden.html)

safetypee 14th Dec 2016 16:32

T D, it's not as simple as you suggest; biased by hindsight? (#279)
We cannot assume that pilots will understand the situation as requiring a cross check.
The PF may be concentrating on what appears to be a sudden pitch upset manoeuvre, the PM surprised by the PF nose-down response, where the situation according to PM apparently requires a nose up manoeuvre, and not necessarily seeing the comparator alert.

The pilots cannot deduce that 'the right side is good' without comparing both EFIS with the stand-by ADI and then confirming which two displays agree; this takes time and mental effort, neither of which may be immediately available.

Trained for confusion, or confused by training. There is a level of confusion where the human cannot manage.

TowerDog 14th Dec 2016 16:40


. T D, it's not as simple as you suggest; biased by hindsight? (#279)
We cannot assume that pilots will understand the situation as requiring a cross check.
They should, this is pretty basic.
Why does some people think it is hard or extremely complicated?
Basic instrument flying, nothing more.

Some of you guys are confusing me: Does a failed screen or attitude indicator justify a death sentence? Is it like loosing both wings and the tail at FL350 over the Atlantic in the winter with no parachute?

NO.

The airplane was perfectly flyable, all they had to do was fly it.
Why do we even argue or disagree?

safetypee 14th Dec 2016 16:41

The certification requirements require the combination of false IRU information and the inability to display a comparator warning be extremely remote(Alf #280 and previous): where -
'Extremely Remote Failure Conditions are those not anticipated to occur to each aeroplane during its total life but which may occur a few times when considering the total operational life of all aeroplanes of the type.'
And
'Extremely Remote Failure Conditions are those having an Average Probability Per Flight Hour of the order of 1x 10-7 or less, but greater than of the order of 1 x 10-9.'

However the particular EFIS design removes the comparator display for pitch values (true or false) greater than 30deg, thus the loss of display and warning is not a combination of two failures but just that of the IRU.
The reported in-service IRU failure rate was less than the required combined value, thus should be considered as not meeting the requirements.

RAT 5 14th Dec 2016 16:50

Surely, or am I being too simple as I've never experienced it, but does 'seat of the pants' come into this analysis somewhere? Hugely difficult if you've spent all your life relying on your eyes; I know. Do we always need a comparator to tell us something is fishy?

I've never been given a frozen attitude or incorrect attitude instrument in recurrency training. I'm sure it would be hugely positive and rewarding, but sadly most outfits lack imagination. The UA box ticking is no big deal, and the new airspeed unreliable procedure frustrating and time consuming before you arrive at the correct input which you should have known all along. The first scenario is recall and piloting, the second is QRH driven.
In this scenario they guys would have had to be very smart & very disciplined without panic. If it goes inverted while you are trying to figure it out, doesn't help.
Why don't we experience some 'limited panel' flying in todays jets? It will teach you a great deal about your a/c and your own strengths & weaknesses. Is it because of "it ain't supposed to happen" thinking?
IMHO training in pre-planned scenarios with pre-planned responses has limited values. In-depth training to understand the a/c & yourself gives a broad solid foundation to apply in a multitude of unforeseen scenarios. The STN B747 was a simple frozen ADI, which caused a crash. It is not the only crash from such an apparently simple isolated failure. I say simple because the PM has correct data confirmed by all the basic performance instruments. It then becomes a CRM and handling exercise; to arrest the situation before a crash.
Never seen it. What a waste of simulator time; an ideal opportunity missed to gain real positive training, and avoid that confusion.

alf5071h 14th Dec 2016 16:58

Tower Dog, not wishing to compare you to Victor Medrew (post 280), but confusion (failed screen etc) is a symptom of disbelief.
Many people could not believe AF or Colgan, but more often the simpler view is more relevant. Humans can be maxed out and in those circumstances they do what some view in hind-sight as 'unbelievable', but at the time, momentarily, was perfectly reasonable for the pilots flying the aircraft.

RAT, 'seat of the pants', yes and pitch trim to fly the aircraft. But there again when the brain is maxed out then the senses may not make sense, even if ever observed consciously.

TowerDog 14th Dec 2016 17:53


. Many people could not believe AF or Colgan, but more often the simpler view is more relevant. Humans can be maxed out and in those circumstances they do what some view in hind-sight as 'unbelievable', but at the time, momentarily, was perfectly reasonable for the pilots flying the aircraft.
AF and Colgan, Yes you are right, unbelivable. Perfectly good airplanes being flown into the ground, or water.
Not being Monday morning quarterback or kicking dead colleagues, got lots of empathy because in many cases, I have been there, done that but survived.
Could tell stories all day about the flying I have done in old and tired airplanes over 37 years in the third world countries with bad maintenance, etc, etc.
This is not about me however, maybe I was lucky, or had a strong fear of dying, or both.
When I see people flying perfectly good airplanes into the ground however, and people on the Internet cooking up excuses about confusing situations or it could have happened to all of us, I tend to disagree and get sad, most of these are so damn unnecessary and you don't have to be Chuck Yeager to look across the panel and see if "his side is good" or with Colgan, add power and push forward on the yoke.
Guess my life is pretty simple.

IcePack 14th Dec 2016 18:18

The reason TD is that you were brought up & have many hours on 37 year old aeroplanes. The latest pilots don't have that experience & have most of their flt time using modern instrumentation.

F-16GUY 14th Dec 2016 18:42


Originally Posted by TowerDog (Post 9609470)
When I see people flying perfectly good airplanes into the ground however, and people on the Internet cooking up excuses about confusing situations or it could have happened to all of us, I tend to disagree and get sad, most of these are so damn unnecessary and you don't have to be Chuck Yeager to look across the panel and see if "his side is good" or with Colgan, add power and push forward on the yoke.
Guess my life is pretty simple.

Its not that simple TowerDog.

Although the pilots in the cockpit and their actions directly relates to the outcome of the situation, there is a company behind, and a regulator behind the company. The regulator has the ultimate responsibility to establish safe minimums for the required training, both with regards to achievement of initial qualification, but also with regards to onwards training with the goal of sustaining a certain level of piloting skills and airmanship. The regulator also have the responsibility to assure that those minimums are adhered to by the company. The company on the other hand has an obligation to provide its crews with the best possible training, but since money makes the world go round, they will most likely only be interested in meeting the minimum requirements.

So as I see it, the regulator is at fault by setting the bar to low.

RAT 5 14th Dec 2016 19:03

One problem I see in todays world of training to minimum requirements is this; the trainers try to beat into crews A.N.C. but, they are also taught to beat in to the crews every time there is a problem, PF "state malfunction." PM does his best and with conformation of PF a QRH is called for. This is the rote of training. DoNot act as a cowboy, on your own, outside the checklist.
So now you have a scenario where nobody has a clue what is going on; the a/c is hurtling terrain-wards; is still controllable if you're quick and decisive, but by whom?? Ah, the big question. Somebody has to make an executive decision and decide what to do without a checklist and the usual nice calm process. There is a bull that has horns that need grasping PDQ. This goes against all the training rituals, but it is pure survival and the brain of some will be confused by the conflict and feel rudderless.
Those of us brought up in a less stringent era, and more pilot orientated, will not feel as restricted about doing whatever is necessary and argue the toss later on. I often found the modern youngsters, when faced with a piloting situation for which there was no black/white SOP or QRH, hesitated. Not their fault, but a training system fault. They had forgotten how to think as pilots first and crews of XYZ second. Normally they can succeed with the latter, but occasionally circumstances combine to thwart your coziness, and the former is required. That attitude needs to be there or you will flounder on the rocks.

Me thinks this debate has been had many times before on here; perhaps more general, but still the same subject. It comes around more than anything else.

F-16GUY 14th Dec 2016 19:37


Originally Posted by RAT 5 (Post 9609546)
Me thinks this debate has been had many times before on here; perhaps more general, but still the same subject. It comes around more than anything else.

Agree, but for some reason nothing (or very little) is done about it by the regulators. I am of the impression that the beancounters have persuaded the regulators that the price we (as a profession) are paying now, is the price of doing business, and the regulators have accepted this offer on behalf of all of us.

TowerDog 14th Dec 2016 19:56


. So as I see it, the regulator is at fault by setting the bar to low.
And the pilots have no responsibility for thinking outside the box, for surviving a TV screen going bad and for basic flying skills?
They can only do what they are thought and nuthin else?

I disagree, but I am from a different area I guess and those years flying bush in Alaska without no books and with no "training" made me look different at flying airplanes. As in "Do whatever it takes" to go home and have a beer.

Enough said, not going to argue anymore, different times I guess, and a good thing this was a cargo flight: A lot less dead bodies being scattered around the tundra in Sweden because of a faulty image generator.


The reason TD is that you were brought up & have many hours on 37 year old aeroplanes. The latest pilots don't have that experience & have most of their flt time using modern instrumentation.
Yeah, time in DC-3 and DC-8s did not hurt my stick and rudder skills, and believe me, old airplanes have their own set of demons built in, and one tend to play the "what if" game on long and dark flights: What would you do if this or if that happened? Kept us awake and sharp on systems and emergencies.

Most of the time we were too tired, 30 hour duty days, bunch of time zones.:sad:


.Those of us brought up in a less stringent era, and more pilot orientated, will not feel as restricted about doing whatever is necessary and argue the toss later on.
Bingo, that was all about surviving, not about stepping on some stupid rule or procedure made up to hold the hand of the weakest link in the cockpit.

F-16GUY 14th Dec 2016 20:51


Originally Posted by TowerDog (Post 9609583)
And the pilots have no responsibility for thinking outside the box, for surviving a TV screen going bad and for basic flying skills?
They can only do what they are thought and nuthin else?

Of course they have some responsibility, but the problem is that from their first flight at a civilian flight school, they are placed in an environment and thought a mentality that does not prioritize or foster basic pilot skills like the skills you earned in the bush. For many young pilots, this is unfortunately and not by their own fault, their understanding of aviation.

I wonder how many of those involved in accidents like this one, Collagen and AF447, actually spent their first 1000-1500 hours piloting an aircraft equipped with a minimal level of automation, thereby learning basic aircraft handling by heart. Instead we now have crews piloting complicated machines with high level of automation, while having as low as 250 hours of real stick and rudder time under their belt. And after 2000 or 3000 hours on type they are considered experienced although their total stick and rudder time still rests at 250 hours plus a few minutes on every second flight. Furthermore, the needed skills will diminish over time, and both pilot and more so their company and regulators have a tremendous responsibility to do something to maintain it.

F-16GUY 14th Dec 2016 20:56


Originally Posted by Small cog (Post 9609619)
Perhaps a bit more 'what if' while sitting idly in the cruise or keeping up to speed with that long list of memory drills might help? Sometimes sitting and analyzing rather than jumping to coclusions and starting incorrect procedure would not go amiss.

Yes, but apparently that part is not thought well enough to some pilots, and the fact that they are not "what if'ing" is not caught in the sim during recurrent training.

TowerDog 14th Dec 2016 21:26


. Of course they have some responsibility, but the problem is that from their first flight at a civilian flight school, they are placed in an environment and thought a mentality that does not prioritize or foster basic pilot skills like the skills you earned in the bush. For many young pilots, this is unfortunately and not by their own fault, their understanding of aviation.
How do we fix it?
Much higher age/hour requirements maybe? Not with a looming pilot shortage, the airlines would be screaming for more warm bodies in the right seat, at whatever cost, just fill the seats..
(One of my buddies is a sim instructor for a well know LCC, now teaching primary guys on the B-737 with 160 to 180 HR total time, then they get spoon-fed from there and into the cockpit of a real 737-800 with 190 pax. Bon Voyage, hope the old man does not get a heart attack)
In my world, I had 5300 hours total time before climbing into a jet the first time, 31 years old. Late bloomer perhaps but I had practiced staying alive for 10 years after I got my Commercial Pilot License.

Don't have the answer, but if I was in charge of training or recruiting, I would look for survival skills, rather than book skills.

MrSnuggles 14th Dec 2016 22:30

Sorry to chime in like this, but this is an area in which I have knowledge. So, my two cents...

I'm really really sure that the regulator in Sweden has all kinds of standards set and measured. I promise you that if someone does it the German way, it is Sweden. Sure, there might be some kind of oversight somewhere, but if there was ever someone to learn a lesson from others regarding unusual attitude cockups, be sure the Swedes had it covered by Jan 1st 2010.

No, what I think is more likely is the trend of misunderstanding the given information, or a lack of interpretation or imagination of what is happening. Airplanes, like cars!, are being more and more complex and require more tuning to comprehend. That is what is deadly.

Remember that in the early days, crashes were often caused by mechanical malfunctions. Clever design and improved skills in building has minimised those incidents. Now, it is the human that is lacking.

megan 14th Dec 2016 22:43


you don't have to be Chuck Yeager
TD, even he belled the cat on one occasion, wrote off a perfectly good aircraft, and very nearly lost his life because his instrument skills were not up to the task in hand.

suggesting that nobody could have survived an instrument failure
I don't think anyone is suggesting that, what they are suggesting is it's another gotcha that has befallen others, and a possibility for those now living to fall into the same trap.

TowerDog 14th Dec 2016 22:51


Remember that in the early days, crashes were often caused by mechanical malfunctions. Clever design and improved skills in building has minimised those incidents. Now, it is the human that is lacking.
Yup, I agree Mr. Swede. You hit the nail on the head.
Airplanes these days are pretty damn idiot proof and reliable, but us being humans, we can still cock it up, and we do. Coltan, AF, Bolivian RJ 85 and many others.
None of us are bullet proof. Had a few close calls being fatigued and too greedy to call it quits. My bad, and a bit of luck.
One learns from experience, sadly these low-time guys who crashed the mail flight in Sweden were just hanging on, not much experience to learn from and the Luck Bucket went dry.
R.I.P. Gentlemen and to the rest of you rookies: Pay attention and get ready for a high tech airplane wanting to kill you: Stay one step ahead and be slightly paranoid.

Uplinker 15th Dec 2016 02:50


Uplinker:
In the light of recent accidents, I think that two other mandatory elements should be added to every SIM from now on:
1. Unusual attitude recovery.
2. Primary instrument failure, identification and recovery.

Mad (flt) Scientist:
The first of those already exists, and was even started at the operator (1.18.3 in the report details this - the requirement was going to be effective in May, the accident happened in January; the operator had started to train their crews....
In 16 years of airline flying and SIMs with two airlines, I have never had unusual attitude training or even practice in the SIM.

ehwatezedoing 15th Dec 2016 04:01

It's not much of an "unusual attitude" from the aircraft itself.
Than "just" a flight instrument(s) caking on you, and you would still continue straight and level without any actions from your part.

Figuring that out when it happen can be the hard part.

...If you see what I'm trying to mean...

darkbarly 15th Dec 2016 07:43

Read and reread the report and still I find something troubles me, the initial reaction timing. According to DFDR elevators were moved by PF at T3, this being 3s after the failure and 1s after the AP disconnect. By this stage, yes, the PFD had risen to 13.7deg PU, so a very rapid pitch (indication) excursion, significantly greater than would be seen (and believed) in normal ops.

Nevertheless, why did PF respond so quickly ( 3s is quick) without ANY somatogravic change of state? I am puzzled by this and it is not explained directly in the report.

It worries me to think that it is within the scope of normal pilot behaviour to react instantaneously to a major change in the displayed flight trajectory without 'feeling' it also. Let me be clear, this is not about som. Illusion or recovery from UA.

RAT 5 15th Dec 2016 09:40

People ask what is the regulator doing? Too often they are not that knowledgeable about our job. They know all there paperwork stuff, but they are not always that experienced as jet pilots. They set minimum standards, very bare minimums, and hope the conscience of the airlines raises their own bar. Some hope. Some airlines think that increased training = increased quality. Not always so. More button pushing does not mean more understanding of the a/c nor more handling skills as a pilot. I find it disappointing that a company gives a few moments of manual handling in the recurrency sim every 3 years, but discourages the same on daily line ops. Lip service. Setting higher minimum standards in the basic TR might be a start.
I have a trainer friend in a national carrier. On their TR courses, be it new cadets or type conversion company pilots, they give the 1st 3 FFS sessions as basic flying. 1st session no automatics or FD's; 2nd session add in FD and some automatics; 3rd session look at all aspects of AFDS and some hiccups. Once that is all understood they then add in all the non-normals & emergencies.
In other operators, whose training is considered good, during the TR course the amount of FFS has been reduced and the amount of basic flying, outside of LST items, is about 30mins. The amount of CMD operating has been increased. It is an astonishing 'poles apart' difference in thinking. If you are a 150hr cadet in one of the latter what chance do you have to learn basic piloting skills, especially as line flying is primarily in CMD at all times.
If the XAA's insisted on FFS 1-3 being the basics of manual a/c control the airlines would have no choice. If command upgrade courses required a demonstration of basic skills to a high standard, the airlines would have no choice.
Leaving everything to the airlines will not create a common industry high standard. The basic LST is simply that; a very basic standard. We need a higher basic level.

deadheader 15th Dec 2016 14:07

too far removed
 
Just to touch on some of the very well made comments above, my simple yet serious query is thus:

Are some commercial pilots now so far removed from the physics of flight/aerodynamics that a simple flight system component failure can more easily result in LoC?

No disrespect whatsoever to those who lost their lives, and to be clear I believe they were victims of the times rather than their own shortcomings (ditto AF447 crew), but, at the moment of indicated attitude change and subsequent A/P disconnect, there were no corresponding changes in altitude, airspeed or vertical speed. The crew therefore diagnosed the problem as one which must have defied the laws of physics/aerodynamics (ditto the AF447 crew).

In other words, the situation the crew assumed they were in, could not possibly have existed. The parallels with AF447 are alarming in this respect.

Additionally, given that an uncommanded change in attitude (& A/P disconnect) is an unusual occurrence, especially during the cruise phase, such an occurrence ought to prompt a logical evaluation of the overall physical/aerodynamic situation before acting, for example; pitch check, roll check, yaw check, power check, altitude check, speed check, VSI check, fuel check etc.

From that point, the issue might have been resolved logically to a successful conclusion.

My personal favourite example of a crew response along the lines of what I'm attempting to convey, and fear may be in decline at least in some circles, is BA009 in 1982. The crew of that flight responded to an utterly unfathomable situation using logic and a thorough understanding of the physics of flight and, as a result, were able to save many lives over the Indian Ocean that night.

All just IMHO of course.

alf5071h 15th Dec 2016 14:23

TowerDog "How do we fix it ... Don't have the answer ..." It would be brave person who would say otherwise.
Thoughts of survival skills are interesting; these skills are associated with a positive mindset, thinking through difficult situations, being prepared for the unexpected.
Perhaps these are the aspects which regulators should be considering, first about themselves, then safety initiatives and aircraft design, and finally about the operators.

MrSnuggles, "... the trend of misunderstanding the given information, or a lack of interpretation or imagination of what is happening ... complexity ..." Patterns can be found wherever we look (what we find is what we look for), but in this instance the mounting evidence from the small number of rare events must be taken as significant. The industry does not have the luxury of time, nor hopefully, opportunity to accumulate more data, which some safety systems rely on.

The industry should not view the human as 'lacking'; this tends to imply failure and a need to improve or mend a broken system.
In accidents like this, the human is limited by inherent capability. Momentarily, situations are encountered where there is little if any opportunity to improve human performance (like those moments of puzzlement in observing an illusion, choosing a viewpoint, but not necessarily one which everyone agrees with).
The human is not broken or in need of replacement - we do our best as we see the situation. The industry has to recognise those situations where the human could be operating close to performance boundaries, and then minimising the number of occurrences so as not to cross this boundary or by providing a larger buffer space for recovery.

The situation in this accident involved an IRU failure, which output misleading attitude, and in parallel the removal (by design) of the alerting system which identified a difference in flight deck displays; a difference which existed because of the nature of the IRU failure prevented removal of the erroneous attitude display.
Most aircraft can have this form of IRU failure and also use a comparator for alerting; however it would be surprising if all aircraft types remove the comparator in the event of an upset - replies sought please. This is an area for accident investigation and safety management.
If a particular aircraft type is an oddity, then the difference needs to be identified before exposing crews to a surprising and confusing situations.
Certification and operational regulation must focus on protecting the human from extreme conditions, and not to treat a human as a hazard to be constrained, instead, improve situations to better enable them use their unique skills of decision and adaptation.
Perhaps the regulators need a 'comparator' alert in their certification.

A side thought; the IRU is a part 25 system, the CL 600 EFIS ... did that have part 23 roots (pro-line), as used in the Challenger?

RAT 5 15th Dec 2016 14:24

Your comments reflects back to my earlier question about whether 'seat of the pants' should have been part of the analysis. I didn't fully understand the photos of the PFD in #265. Are these both of the same PFD showing a sequence in display, or are they LHS & RHS? It'll help me understand. As DH asks: if you are in level 1G flight and there PFD says you are in upset flight does your backside not tell you eyes that 'it can not be true'? This is not not about a false level from your inner ear, it's simple g loading on your body.
This situation & experience is a classic simulator training exercise, but in 35 years I've never seen it. It teaches so much: knowing when to sit on your hands; careful analysis of the situation without a checklist; CRM about what to do about it; plus other aspects.
Equally I've never been given blocked static vent (only pitot tube). Simulator being wasted?

alf5071h 15th Dec 2016 14:53

RAT5, 'seat of the pants' (acceleration), perhaps one of those senses which is degraded in surprising and stressful situations, or during high workload. And the eyes, or the interpretation of what is seen, can lie, this sense can differer or conflict with information from other senses.

Humans do not have a 'comparator' detection and alerting system. At best we might experience similar situations in training and flag the need for caution when encountered in operation, e.g. after 'seeing' (understanding) the Muller-Lyer illusion, it may be possible to identify similar situations and avoid them, not be caught out by the misleading information.
Illusionary effects can be used to aid safety, cf M-L illusion road markings when approaching a narrow bridge; ... but that might not prevent a double decker bus driving under a bridge which is to low; the situation is assessed on where we 'look' and what we 'see' (or wish to see - bias or prepositioning from experience/training)

Most simulators, as good as they can be, are unable to simulate prolonged acceleration, and thus are very weak in creating illusionary effects.

RAT 5 15th Dec 2016 15:54

alf: Interesting; and hence my thoughts as a question not a fact. I agree about the sim limitations and our reluctance to overcome what our eyes have been trained to do over many years; plus the startle/stress element of such a scenario.
And that brings us back to the use of simulators and showing crews what gotchas & traps are out there; so enforcing your comment about we might experience similar situations in training and flag the need for caution when encountered in operation, e.g. after 'seeing' (understanding). I think simulators are under-used in this way. One can show many real life events in this way. In there briefing phase you can go thought the 'what if' discussion and then demo it and let the crew play; it does not need to be a full LOFT, just enough to get the point across and let them see the dangers and realise the limitations: e..g the blocked static vent on the Peru B757. Let the crews experience what confusion is caused by the instruments appearing to oppose their inputs and 'teach' what to do about it. A full blown LOFT takes a long time, and in that same time you could introduce various scenarios and thus impart a much larger amount of knowledge & understanding for use should any of them ever happen.
After the B777 SFO some TC's said they told their students about the trap in the A/T. Did they demo it? Difficult on the line. How many airlines now include it in their TR syllabus as an exercise? There are numerous other gotchas we've seen, and after the crash of serious incident we discover it was not the first time in the world. After the AB landing in the trees at Basle; how many airlines include that trap in the TR? Did it not happen again in India? Maybe slight differences in reason, but it still landed short of the runway in idea as the crew watched in horror.
How many G/A's have led to crashes, or near crashes, due to a gross out of trim situation of a mis trimming. Enough to introduce it as sim demo exercise don't you think.
I always used to learn more from my mistakes than successes. A simulator is a great tool for showing what can go wrong, how easy it is for it to go wrong, what it looks like when it goes wrong, how to escape from it and how to avoid the trap in the first place.
This goes well beyond the tick box 3.4 on the training syllabus, but it'll keep you safe well into the future.
Let's use the tools we've got to more effect and to their full potential. More training less box ticking.

Uplinker 15th Dec 2016 16:20


ehwatezedoing
It's not much of an "unusual attitude" from the aircraft itself.
Than "just" a flight instrument(s) caking on you, and you would still continue straight and level without any actions from your part.

Figuring that out when it happen can be the hard part.
Yeah, see point 2 in post # 301

TowerDog. Yes, your 5,000 hours of flight on (I guess) the basic T clockwork instruments has stood you in good stead. Now we have cadets flying about 100 hours on a modern light aircaft and then straight onto a PFD type presentation, and maybe that is the problem - It's not their fault but maybe they can't assimilate it properly.

If you think about it, on a PFD you 'climb up' the pitch angle, the V/S scale and the Altitude tape if you pitch up - to a higher pitch angle, greater vertical speed and higher altitude - and decrease all three if you pitch down, so they all react to pitch changes in the correct sense.

The speed tape though reacts backwards, if you pitch up, the tape moves the wrong way to a lower speed and ditto to a higher speed when pitching down. I wonder if this tape moving the 'wrong' way confuses us on a deep subconscious level? If the speed tape were the other way up, so higher speeds were lower down the scale instead of above, then the speed tape too would react in the correct sense to pitch changes. You pitch down, and you go down the speed tape to a faster speed, pitch up towards a slower speed.

Round clockwork instruments don't have the up and down, but clockwise and anti clockwise movement. If one pitches up, the speed dial rotates anti clockwise, pitch down, it rotates clockwise. Perhaps this round movement is easier to associate with the up or down pitch changes than a 'backwards moving' straight, vertical speed tape is?

TowerDog 15th Dec 2016 16:57


TowerDog. Yes, your 5,000 hours of flight on (I guess) the basic T clockwork instruments has stood you in good stead.
More like 13,000 hours on steam gauges and 3000 hours on glass.
Yes, I get your point, perhaps glass cockpits with speed tape reacting backwards and everything on 1 screen, makes it less obvious what is going on?

Not sure. Perhaps young pilots born and raised on glass, it would be second nature to them, no idea.
I never liked the glass cockpits and the "boxes", kept fumbling in the beginning.
Still do I guess.
Not my cup of tea.

No idea what the background of these pilots were, but only 3,300 hours each.
Looks like they could have used more time and more training. :sad:

MrSnuggles 15th Dec 2016 18:12

Uplinker

Yes, research has shown that humans comprehend angular movement as instinct. This means that rotations (of legs or clock handles) are easier to interpret correctly than vertical movement like the speed tape. The same is true of speed on your car. It is easier for the brain to know how fast you are going by seeing the rotation of the traditional round dial speedometer. It is harder for the brain to interpret the digital numbers on the modern display. Remember that numbers are taught in school, but moving around is not! When you are taught the numbers, your brain has already worked out angular movement by instinct for several years!

I am very confused why airplane designers still choose to show speed on a tape when this is known.

ETA: I realise that I may use some words incorrectly. I apologise for any inconvenience this may bring to your inner grammar nazi. :-)

andrasz 15th Dec 2016 20:19


Originally Posted by darkbarly
According to DFDR elevators were moved by PF at T3, this being 3s after the failure and 1s after the AP disconnect


In my reading this is clear proof that the reaction was subconscius, probably the result of a rather rigorous training that indoctrinated the need to follow ADI regardless of what one's senses dictates. This approach and training has saved many a day and made aviation much safer globally than it was 30 years ago - yet in this case it appears to be the direct cause.


I mentioned in a previous post that an above average crew would have had this figured out in no time, however traning is there to bring up below average crews to performance levels of at least average. With a clear repetitive pattern emerging with broadly similar circumstances of crews losing control due to a simle and recoverable fault, it will be interesting to watch how training regimes try to adapt without losing some of the progress that was made.

Intrance 16th Dec 2016 00:37

@TowerDog:


No idea what the background of these pilots were, but only 3,300 hours each.
With all due respect, I think your amount of hours and experience may distort your view just a slight bit. Yes, 3300TT is only a fraction of your experience, but it is still several years worth of flying even if you would hit your yearly limit all the time. Depending on their backgrounds they could have a combined flight experience of 10+ years which is not insignificant... As you know there are planes being flown full of passengers with less experience on the flight deck and often coming from just one of the pilots.

I have yet to read the full report, but from the comments here it does sound like they could have used a background in older planes with steam gauges. Cross checking is second nature there, at least in my experience on the type I flew; "Hmm, my ADI is tumbling away, is yours still OK?".

TowerDog 16th Dec 2016 02:51

I belive the full report is available right here on this thread.
Everbody could use a few more years or a few thousand hours more in the seat, especially if
Some sinister tv screen failure is anticipated, or not.
If not, stay sharp and be a bit paranoid young guys.
Flying is easy, until it is not easy anymore:
This accident, AF, Colgan and a bunch of other crashes should wake you up.

oleary 16th Dec 2016 04:08

Loss of ADI
 
Canadian Beaufort Sea in December 1979.

Blacker than the inside of a duck in ice fog and darkness.

Aircraft was an Sperry IFR Bell 212.

We picked up off the rig deck into a hover and turned into wind (away from the rig lights).

I pulled collective as the FO called 20', 40', rotate.

As I rotated into the blackness my ADI slowly tumbled with NO FLAG.

I looked at the ASI, VSI and compass. All normal.

I looked at the standby horizon and it was normal too.

I said to my (low time) FO, "I'm losing my ADI get ready to take control if I ask".

This whole thing took maybe 5 seconds.

We flew the a/c IFR for a week with a duff captain's ADI.

Times were different then.

I had a similar thing happen (December again) with a Sikorsky 61 night IFR slinging north of Rea Point, Nunavut (Lougheed Island) at about N 78.

Same result.

FWIW, I am also current on glass cockpits in fixed wing.

Mac the Knife 16th Dec 2016 05:09

A question for you guys.

Suppose you were bimbling along quite happily at cruising altitude to wherever and you suddenly had an overspeed warning with an IAS of Mach 1.2.

Would you immediately react accordingly (switch off AP, pull back on power, pull up nose - or whatever you do) or would you say "Oh balls! The fricken computer's on the fritz again!".

I ask, because we have lots of monitoring equipment in the operating theater and it does, occasionally, start talking nonsense - one's first reaction is to look at the patient and if they are pink and well-perfused there can't be THAT much wrong. Then you start trouble-shooting the monitors.

Just asking....

F-16GUY 16th Dec 2016 05:55

Me actually thinks amount of total flying hours is totally irrelevant. What counts is total amount of training received within the not so distant past. Skills erode over time, some faster then others. Pilots need to be exposed to situations that sharpen their basic skills on a regular basis and not for 30 minutes every 6 months.

Sim or actual airtime (without pax) is expensive, so the companies do not have any incentive other than to cut it into the absolute minimum required by the regulator. And regulators apparently dont see it as a big issue yet.


oleary,

It does not count in a chopper. If you see more than 3 degrees bank angle or pitch, you immediately know the ADI is broken :-)

oleary 16th Dec 2016 06:46

F-16 guy
 
Dunno about that. I have about 8K hours of hard IFR in helicopters, a bunch of that with a sling load. And I have had some of my night slinging trainees manage to get the ADI all white, then all black, then all white again. ;)

F-16GUY 16th Dec 2016 07:18

I hope they payed you well, cause that would have scared the crap out of me:uhoh:

RAT 5 16th Dec 2016 10:37

Many guys have commented about failures of system being confirmed by 2 parameters. I've worked for only 1 operator who had that written into the SOP's. It makes common sense. That was in an era before cadets.
Since then, and the during TR courses I've given to cadets, I've tried to suggest that this philosophy should be written into the teaching. No success. Very disappointing. Looking for that 2nd confirming parameter encourages a slight 'sit on your hands moment' and less rush.

It was even written that in an RTO due loss of thrust, the swing/yaw of the a/c was the 2nd parameter. Now I see guys being taught RTO based just on N1 gauges.
In this case, seat of pants g might have been the 2nd parameter. If the instrument is rolling & pitching, but you ain't spilling the coffee, it should cause a question. But are cadets, even old farts, taught this in the sim? I doubt it.

There are various scenarios where a 'it can't be happening' moment could occur. Remember the takeoff brief about RTO <80 & >80. There I was passing 100kts and the takeoff config horn sounded. 1st reaction was, "this should not be happening." I noticed a split flap gauge. 2nd reaction was "doubt, and when there's doubt there is no doubt, so we're better RTO-ing." It was home base, long enough runway. You could put it under the 'a/c unsafe to fly' category. It turned out to be a flap sensor that caused a split in the needles (not the flaps) and locked out the flap system. The point being there was a large ? floating around the flight deck for a couple of seconds.

RAT 5 16th Dec 2016 13:34

Oh Dear! Really? Idle descent engine failure is a gotcha for that, but takeoff???

Herod 16th Dec 2016 13:43

Standard brief in my old company: "Confirmed by two or more parameters"


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