Falling for Traps...the sucker hole and others

[RAT 5]

There have been a few B737 crashes in recent years, that I know of, where the crew thought CMD was in charge, but it wasn't. They took their eye off the ball until "bank angle' was screaming at them, in the night with no horizon, and then came the smoking hole.
One, they didn't monitor, but became complacent; second they couldn't recover from an upset attitude.

[DozyWannabe]

Originally Posted by doubleu-anker

"anyone remember how the L1011 in the everglades was on altitude hold and then descended into the ground?"

Altitude hold was not selected, certainly not engaged, at the particular time in question and no one on the flight deck picked it up either.

If I recall correctly, what actually happened there was an unexpected design issue. Namely that if the autopilot on one side was calibrated to disengage with less yoke force than that on the other side, then the ALT HOLD indication would go out *only* on the former. In the case of EAL401, the PF at the time was the F/O in the RHS - and the presumption was that it was the Captain who inadvertently disengaged the autopilot when he turned around - his light would have gone out, but the F/O's would have remained lit.

Of course, the F/O's duty was to maintain his scan, which he did not - but the failed landing gear indicator light that started the chain of events was only reachable from his side, so his distraction was understandable.

On a tangent, I was re-reading a book the other day that said based on some statistics (which I'll look up again), when it came to otherwise serviceable aircraft crashing, something like 70-80% of those accidents involved flights which were late, or in a position where a hold or go-around would make them late.

[Turbine D]

Original Quote by Dozy: If I recall correctly, what actually happened there was an unexpected design issue.

Maybe this will help you really recall correctly, The NTSB never said there was a "design issue"....

The NTSB investigation discovered that the autopilot had been inadvertently switched from altitude hold to CWS (Control Wheel Steering) mode in pitch. In this mode once the pilot releases pressure on the yoke (control column) the autopilot will maintain the pitch attitude selected by the pilot until he moves the yoke again. Investigators believe the autopilot switched modes when the captain accidentally leaned against the yoke while turning to speak to the flight engineer, who was sitting behind and to the right of him. The slight forward pressure on the stick would have caused the aircraft to enter a slow descent, maintained by the CWS system.
Investigation into the aircraft's autopilot showed that the force required to switch to CWS mode was different between the A and B channels (15 vs 20 pounds respectively). Thus it was possible that the switching to CWS in channel A did not occur in channel B thus depriving the first officer of any indication the mode had changed (Channel A provides the captain's instruments with data, while channel B provides the first officer's).

[AirRabbit]

Flarepilot - you're not wrong at all ... the autopilot was indeed selected on that EAL L-1011, however with all the cockpit conversations and all the activity trying to figure out why it was that the crew didn't have "3 green" lights, the suspicion was that the F/O (who was flying at the time) inadvertently pushed on the control column (probably trying to shift his position in the seat) and, in doing so, disconnected the autopilot - or at least the altitude hold function of the autopilot. It was THIS action and the accident investigation that followed, that recommended the installation of the aircraft autopilot disconnect warning tone and the flashing light to activate whenever the autopilot is disconnected … and, as you all probably recognize, it will keep beeping and flashing until the autopilot disconnect switch is depressed.

[flarepilot]

air rabbit

thanks...I recall this vividly as they made a movie about it and showed one of the pilots pushing forward ...I have always hated control wheel steering.

I am glad this thread is causing some thoughts and words to be exchanged.

I would also like to comment on the UPS crash...it really boils down to being too low at the wrong place.

I no longer participate in the UPS crash thread...but the call, ''runway in sight'' may have been to allay fears of NFP about leaving the safety of the MDA.

Much has been written about the constant descent technique and the ''dive and drive'' technique...I had been diving and driving for over 10 years before I had ever heard it called that.

but in the final analysis...one cannot leave the MDA without a sure thing.

[DozyWannabe]

Originally Posted by Turbine D

Maybe this will help you really recall correctly, The NTSB never said there was a "design issue"....

They might not have, but I'd certainly call it that! And this isn't a dig at our cousins, because IIRC the autopilot system in the TriStar was developed by the UK team who worked on that of the Trident - later hired by Lockheed.

In any case, the NTSB were more concerned about the fact that an entire crew could be fixated on the behaviour of a single light* to the exclusion of flying the aircraft! The autopilot channel imbalance was considered a relatively small contributory cause.

* - in a bit of truly tragic irony, one of the crew points out how much effort they're putting into verifying this single light on the CVR, shortly before the impact into the Everglades.

[Turbine D]

They might not have, but I'd certainly call it that!

I would be kinder to the L-1011, were it not for this airplane (which was extremely well designed in its day), the large commercial engine division of Rolls Royce probably wouldn't exist today, the Trent series would never have evolved from the RB211 series...

[DozyWannabe]

Originally Posted by Turbine D

I would be kinder to the L-1011

Hey, by all accounts I've heard it was a brilliant machine and I have no reason to doubt it! No aircraft is even close to perfect when first in service and EAL401 happened very early in the lifecycle of the type. When you think of what happened to the DC-10 in the following years, I'd say Lockheed did well in a technical sense, if not commercially.

@AirRabbit - I'm pretty sure it was believed to be Captain Loft that inadvertently disengaged altitude hold, as he was the one turning around in his seat. Also, had it been F/O (and PF) Stockstill that disengaged altitude hold, his light would have gone out. Not that it matters in any sense other than nit-picking accuracy...

[AirRabbit]

@AirRabbit - I'm pretty sure it was believed to be Captain Loft that inadvertently disengaged altitude hold, as he was the one turning around in his seat. Also, had it been F/O (and PF) Stockstill that disengaged altitude hold, his light would have gone out. Not that it matters in any sense other than nit-picking accuracy...

No sweat Dozy ... nits are there to be picked and some are more meaningful than others. Surely, one of them inadvertently "knocked off" the A/P and obviously no one was "minding the store." Who it was or wasn't isn't the issue - it's what happened that's important. See ya 'round the pattern.

[DozyWannabe]

Originally Posted by AirRabbit

Surely, one of them inadvertently "knocked off" the A/P and obviously no one was "minding the store." Who it was or wasn't isn't the issue - it's what happened that's important. See ya 'round the pattern.

Well, kind of. It's one of those accidents where words to the effect of "crew error" are what went down in the record, but understanding the circumstances that led to those errors being made is also pretty damned important too.

Overall, the crew lost situational awareness due to futzing with the bulb and the PF wasn't scanning the basic instruments. But leaving it there only tells a fraction of the story - the contributory circumstances include the autopilot computer imbalance, the fact that this leg was essentially the crew's last before the holidays, the lack of clearly defined task delegation and the existing systems warnings being somewhat inadequate.

[AirRabbit]

Well, kind of. It's one of those accidents where words to the effect of "crew error" are what went down in the record, but understanding the circumstances that led to those errors being made is also pretty damned important too.

Overall, the crew lost situational awareness due to futzing with the bulb and the PF wasn't scanning the basic instruments. But leaving it there only tells a fraction of the story - the contributory circumstances include the autopilot computer imbalance, the fact that this leg was essentially the crew's last before the holidays, the lack of clearly defined task delegation and the existing systems warnings being somewhat inadequate.

Of course understanding the errors is important - and I believe it goes right back to training. Of course, I understand that this was some time ago, it was night, end-of-trip flight, holidays on the way, probably tired, etc. I agree that "the pilot flying wasn't scanning the basic instruments" ... but, said another way, "the pilot flying, wasn't" ... full stop. I understand the system warnings were not what they are today ... but they are what they are today because we have been attempting to insert a warning of anything that goes beyond what someone believes is a limit to which we should let something go ... altitude deviations ... speed warnings ... stick shakers and horns ... claxons and flashing lights ... all with the acceptance of the fact that we need a warning system to bring the pilot's attention back to where it needs to be, as a direct result of the airplane exceeding a predetermined parameter that someone, someplace decided wasn’t good or drives the attention of the crew to a change in airplane configuration. I’m waiting for a requirement for a “gong” to sound when the landing gear reaches the “down and locked position and the doors have closed” – because someone someplace is going to say that the light in the handle extinguishing isn’t good enough – because you have to see it. OK, I admit, warning systems are mostly a good thing ... but I also think that relying on a warning system as a routine matter says that we're content with the training we all received and cannot expect pilots to constantly monitor the progress of the flight and we really need to supplement training for that function with warning systems. Well, that's probably OK in some situations in some environments. BUT ... I'd like to push the training aspects of someone always being in direct control of the airplane. Also, in that particular vein, I like separating the concepts of "...turn on George and let him fly..." and "you are in control of the airplane through George's abilities." The pilot flying should always be in control of the airplane and that pilot has the choice of using the manual controls provided or the automatic controls provided. An autopilot should never be in control of the airplane.

In this particular case (L=1011/Everglades), I'm not at all against having a warning system to indicate that the autopilot or some mode of the autopilot has been disconnected ... but that doesn't - in my view - release the crew (primarily the pilot flying the airplane) from the responsibility of ensuring that the airplane will be under direct control at all times. We can write it in the manuals (and we have) ... we can describe it during training (and we have) but we need to stress it in training ... over and over and over and over .... and then over again. And we should do that every training visit for the first (pick a number of) years of employment with the airline. The same holds true for other basic training issues - redundancy in training works - and it works a lot better than most of the newer, more fancy training concepts. Newer is often good, but too often NEW replaces OLDER methodologies without having been “tried and verified” ... and I, for one, don’t want to find out that the NEW wasn’t quite as good as the OLDER it replaced when we bring the pieces out of the bottom of the hole.

[DozyWannabe]

Originally Posted by AirRabbit

I'm not at all against having a warning system to indicate that the autopilot or some mode of the autopilot has been disconnected ... but that doesn't - in my view - release the crew (primarily the pilot flying the airplane) from the responsibility of ensuring that the airplane will be under direct control at all times.

Personally, I am and have always been uncomfortable with the idea of "causes", especially as they relate to crew performance. In that particular case, the way the systems and training worked could and did "set a trap" of the kind we're discussing. The chain of events are as pure an example of Murphy's Law as I can recall - the crew were trained to understand that if the Alt Hold indicator light was on, then the system was holding altitude. I'd be very surprised if the F/O would not have switched to basic scan if his light had gone out as it was supposed to (or indeed would not have maintained a full scan throughout had he not been the only crew member who could reach the gear light assembly). The "C-chord" warning chime indicating a deviation from assigned altitude issued only from the speaker at the FE console, but the FE was in the forward bay at the time trying to check the gear through the porthole.

These were the days before CRM and its central premise of specifically delegating tasks so that every member of the crew should be aware of what they are supposed to be doing, with the Captain responsible for delegating those tasks in the most appropriate manner. With 20/20 hindsight we can always say that the Captain should have taken control in order to free the F/O up to work with the FE in troubleshooting the gear light, or that they should have had the FE go into the equipment bay right at the beginning and dispense with the light completely.

But that is indeed hindsight - the fact is that there was no overt negligence on the part of any member of the crew, and while mistakes were obviously made, the mistakes themselves were fairly minor if taken in isolation. The CVR indicates a crew that were diligently trying to solve a problem, and tellingly it is as soon as the Captain effectively releases the F/O from the task of solving the gear light problem that the F/O finally has time to resume his scan and cross-check - and he notices that they are too low and descending.

Anyways - think we've covered that pretty much to death - so here's the biggest "trap" for pilots I see in modern airline operation and it isn't confined to the flight deck (in fact it only appears there rarely), and it relates to what AirRabbit was saying about responsibility. Based on the material I've read over the years I think the most insidious trap is the disconnect when it comes to pilots' (primarily line captains') autonomy from management. Aviation lore and history has it that once the doors are closed, the captain is responsible for everything that happens on the aircraft until disembarkation. The only way I can see this being a fair arrangement is if that autonomy extends to the operation of that flight as a whole, and that is only possible when management respects that autonomy to the letter and backs their captains to the hilt (except in the case of obvious and proven wrongdoing).

On paper, that relationship is sacrosanct and technically a Captain can choose not to operate a flight if he or she believes the operation will be unsafe or otherwise compromised. Yet what I see from experience is a degree of management coercion that is getting worse, and on occasion I've also heard tell of unscrupulous management actively throwing their pilots under the bus and using the rule of autonomy to do so - even in cases where the coercion was blatant.

Of course, the nature of commercial aviation (the clue's in the name) means that there are always going to be business considerations that influence management, and the management will in turn influence their crews. I get the feeling that, arcane as it is, the seniority system originated as a way of limiting management interference with operations (say, by punitively restricting career development if a pilot refused to fly on safety grounds once too often) - but when I hear of things like fuel-burn league tables and tacit acceptance of "crash pads" substituting for proper rest, I have to say my blood runs a little cold. What makes it run a little colder still is when I think of PJ2's eloquent summary of the current status quo - namely that while airline management in the past definitely applied pressure to their crews, at least they tended to have aviation specialists amongst their ranks. Today's MBA generation see it purely as a numbers game, and the fact is that they can dodge responsibility when things go wrong by citing the captain's autonomy rule.

[AirRabbit]

Of course, the nature of commercial aviation (the clue's in the name) means that there are always going to be business considerations that influence management, and the management will in turn influence their crews. I get the feeling that, arcane as it is, the seniority system originated as a way of limiting management interference with operations (say, by punitively restricting career development if a pilot refused to fly on safety grounds once too often) - but when I hear of things like fuel-burn league tables and tacit acceptance of "crash pads" substituting for proper rest, I have to say my blood runs a little cold. What makes it run a little colder still is when I think of PJ2's eloquent summary of the current status quo - namely that while airline management in the past definitely applied pressure to their crews, at least they tended to have aviation specialists amongst their ranks. Today's MBA generation see it purely as a numbers game, and the fact is that they can dodge responsibility when things go wrong by citing the captain's autonomy rule.

While all of the above is true we can’t overlook the fact that very few people will take jobs with any significant responsibility without considering what they are going to be paid for doing that job. Some are focused on “downstream” success (usually those higher in the corporate hierarchy) … and others are focused on the end of the week/month (usually those a bit lower in that hierarchy). Certainly the airline seniority system very likely was instituted to provide a personality-free and a personal-opinion-free promotional scheme. Having been in this business for the time I have, one of the many conclusions I’ve reached is that there is more than a slight dearth in the availability of agreement of the safety level that must be achieved (significantly including the amount of risk that should be taken to complete the task at hand) and just who it should be that determines that whatever is done is satisfactory.

The answer that was agreed upon was the development of a regulatory authority. In the first decade of the 1900s, navigation problems were found to be in need of improvement along with some level of standardization. It was not long after that decision that attention broadened to include the establishment of some commonality behind the actual construction of the airplane (and a recognition that federal involvement would be necessary) and for the commonality of piloting expertise. It was thought that these steps would be necessary to help ensure the viability of a commercial venture based on aviation. Without getting into something that is very likely an unwanted history lesson, the “rest of the story” is pretty clear. The regulator constructs the proposed rules and the public gets an opportunity to comment on the good, the bad, and the ugly of those proposals. Unfortunately, for what seems to be a very long time, the “understanding” was that “those who could … flew … and those who couldn’t … wrote rules” … and, for quite a while that was more true than not. However, I believe those days have been long gone, anyone who has had “up close and personal” dealings with any of the regulatory authorities can very likely attest to that fact. Unfortunately, any individual within that regulatory authority is, or likely will soon be, subject to the political issues that affect any government entity that ultimately answers to their public. The result is usually found to be the most effective political solution for the most solidly connected politically. Just to maintain some sense of rationality – this is not restricted to governmental operations … as many of you know, exactly the same issues are found in virtually any business – and particularly so for those businesses that have a multi-level management structure.

Lest anyone think I am in favor of “fuel-burn tables” and “crash pads” – let me make it clear, I don’t. However, with regards to “crash pads” at least, the airline or the regulator could make it a requirement that the flight crew member be in the local area of the departure flight location for a minimum of 24 hours before that departure OR require flight crew members to reside in the same state/county as the departure airport. As most airlines don’t require a specific living location requirement (as most employers do not make such requirements) it seems that virtually all of the “crash pad” stories are essentially self-inflicted. With regards to “fuel-burn tables,” I would think that such information provided to the appropriate regulatory authority might have something to say about that … yeah, yeah, I know … no one wants more rules … but that’s what is apparently happening now … right?

It’s my opinion that a reasonable set of training and checking rules that are followed by all airlines would prevent many executives in the airline business from believing that they can profitably run an airline by cutting some of the most severe costs – one of which is certainly training. If an airline wants to operate airplanes with minimally paid crews, but are in compliance with the rules outlining what is required to get and keep those crews qualified and current … get and keep the airplanes they operate up-to-date with inspections and maintenance practices … with landing fees essentially equal at any given airport … fuel costs essentially equal at any airport … purchase price and financing charges at least similar, and more likely close to identical from airline to airline (particularly for the same make, model, series airplanes) … resulting in those airlines having a more narrow margin regarding their direct and indirect “operating” costs - I say ... BE MY GUEST. I not sure that anyone would be in favor of a governmentally run grouping of airlines – as that would more than likely degenerate into a single airline in each country – and I don’t see how that would serve the populace of those countries. As I see it, the bottom line is a rigorously developed and held standard of training and qualification requirements for flight crews, equally rigorous development of standards for maintenance and inspections on the equipment, operating in a commercially viable environment where the public will determine the viability of additional competition in any market – and airline management will determine whether or not it’s in their best interest to chase unruly drops in passenger ticket prices to be able to support the salary/benefits packages they offer to their employees – including maintenance and operations personnel.

Before anyone jumps me … I fully recognize that owning and running an airline successfully is not for everyone – as we have all seen. Some individuals have the “knack” for doing so … and clearly, others do not. But compromising the quality and safety of an airline operation is something I think no one can accept – nor should they have to.

[Teldorserious]

Just let the autopilot fly the plane and trust the SOPS, that way you won't have to worry your little heads about these pesky advanced airmanship things.

[bubbers44]

How well did that thinking work for AF RIO to Paris? Pushing buttons and SOP's don't always work if the guys up front can't fly unless the autosystems keep working. At your age you haven't figured it out yet. Someone in the airplane has to be able to manually fly the aircraft. Unfortunately the only AF pilot that knew how to fly manually was taking his rest break. The button pushers on automation crashed a perfectly airworthy aircraft because they couldn't fly manually. Every year this is going to be a bigger problem.

[Teldorserious]

Sorry Bubbers - They finally got me, like in the Invasion of the Body Snatchers, I now drink the kool aid..

In my best robotic voice...

All flights will be done on autopilot, all decisions are found in the SOPs manual, I will execute company policy and do what am told and how. All I want is a job sitting in a plane. My function is to warm a seat, my function is to read a check list. My function is to sit in this seat until such time I am told to sit in the other seat. My name is Locutis, I am Borg, you will be assimilated, resistance is futile.

[doubleu-anker]

Teldorserious

Your last paragraph summed it (you) up. Robots!

[flyboyike]

Originally Posted by thing

You don't need to know how to do an NDB approach anymore? I find that surprising. I'm not an airline pilot by the way, I'm a GA pilot but you certainly have to do NDB approaches for the UK IMC rating. Hand flying an NDB hold and approach in crappy weather with a fixed card ADF concentrates the mind wonderfully.

Hasn't been required in the US for quite some time. All that's required is a precision approach and a non-precision one of some kind. That's not to say the examiner might not ask you to fly an NDB approach if your aircraft is properly equipped, but it's not a requirement.

[Pugilistic Animus]

These days stalls seem very frequent with or without unreliable airspeed. There's Colgan AF snd a few others AeroPeru, Birgenair that have had catastrophic stalls the problem imho seems to go way back to primary training in that area.. .stalls at these number are simply not acceptable in moden aviation.

[RAT 5]

I'd always thought that, as a basic philosophy, it would be a requirement for an operator to be able to control the system manually when the automatic control failed. It's called manual over-ride. Now, surely that applies to an aeroplane full of trusting have faith pax? The annual test criteria do not address the real modern issues. An engine failure is easy: a subtle loss of some automatics/nav systems etc. is less so. It is this type of failure that leads to many incidents/accidents; yet these are not tested nor even trained. Thus the original premise is not satisfied.
I still say that the pax expect pilots to be their last insurance policy and when necessary it pays out in full. Is that viable today? Ask yourself? Can you do it?