AF447 Vanity Fair article

seagull said:
I just grabbed the quote to respond, was not meant to be directed at any one person.

How do you define "multiple cascading failures"? I would argue that most U.S. accidents could be so contributed. Regardless of that aspect, I would state that most "normal training" is not broad enough in scope to handle the "corner-points" as I said above.
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Well again, that was Boris' term. My take on it was failures that aren't in the "book" and not trained for. I guess something like an electrical bus failure that leads to an electric hyd pump failure, with the engine driven pump on MEL.

Hell I don't know.
 
ATN_Pilot said:
Yes, but the design flaws aren't in the flight controls, which is what we all ultimately revert to in an emergency (aviate, navigate, communicate). The world goes to hell in a hand basket, we grab for our flight controls. We don't start punching buttons in the FMS or analyzing schematics.

Looking at the Asiana accident, there was clearly a lack of understanding of a system. But that system was the autopilot, not the primary flight controls. I'll give @Boris Badenov a woody here by saying that the whole thing could have been solved by simply clicking off the automation and going to the old fashioned yoke, rudder, and throttles. And that's not an indictment of the crew, to be clear. It's an indictment of many things, from culture to training. But it's definitely not an indictment of Boeing flight control design philosophy.
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Were it that simple! The lack of understanding of the system was also a consequence of Boeing not publishing anything about the matter until it was "discovered" during 787 flight test. The problem with just "turning it all off", which, you are correct, would have worked, is that it is only with the benefit of hindsight bias that it is clear that was needed.
 
seagull said:
I would say it was a combination of design issues and training, for both the way that check airman are trained as well as pilots.
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Maybe FLCH is a flaw, but I don't see it that way. If you understand the logic, it isn't hard to use properly. It introduces threats in certain scenarios, such as hand flying and not following the flight director. But we train for that scenario, and also prohibit the use of FLCH on approaches inside the FAF.

I personally wouldn't use FLCH on a "high" visual approach. Of course, I'd probably have the autopilot off and FD off too...
 
seagull said:
Were it that simple! The lack of understanding of the system was also a consequence of Boeing not publishing anything about the matter until it was "discovered" during 787 flight test. The problem with just "turning it all off", which, you are correct, would have worked, is that it is only with the benefit of hindsight bias that it is clear that was needed.
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All true, and I should follow my own advice about remembering hindsight bias. :)
 
PhilosopherPilot said:
Maybe FLCH is a flaw, but I don't see it that way. If you understand the logic, it isn't hard to use properly. It introduces threats in certain scenarios, such as hand flying and not following the flight director. But we train for that scenario, and also prohibit the use of FLCH on approaches inside the FAF.

I personally wouldn't use FLCH on a "high" visual approach. Of course, I'd probably have the autopilot off and FD off too...
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Well, in other OEM aircraft the autothrottles will NOT let you stall, and will always "wake up". There is no excuse for that. The fact that you can train to deal with the flaw does not change the fact that it is there. Further, if you have been used to flying aircraft that do NOT have this issue, you will not be expecting to encounter it, particularly when it is not really trained or demonstrated, which it was not at the time.
 
ATN_Pilot said:
Come on, don't you fly it? You know the differences. Sticks are independent, they average inputs when both are moved simultaneously, one can override the other without feeling it, the throttles don't move in autothrust, the list just goes on and on.

And whenever someone who loves his Airbus responds to any of this, it always involves how much he likes having a tray table. :rolleyes:
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Well, for starters, I really like having a tray table.

Sticks averaging the input is common sense. In the RJ or Cessna, if one person pulls back with 20# of force, and the other pushes forward with 20# of force, guess what, the movement is averaged, and the control surface doesn't move. Same exact design idea with the Airbus.

While one can override the other with the push of a button, I dare say, the Airbus makes it more obvious than in a "normal" airplane. A loud "DUAL INPUT" and a whole bunch of flashing lights go off when both are moved at the same time and a "PRIORITY LEFT/RIGHT" is heard. I would say most times when two inputs are made on another airplane I have flown, I didn't even recognize it being done until looking over. This is actually a good design, as it means not having to fuss with disconnect pulls while the airplane is rolling out of control (an eye opening sim event comes to mind).

Throttles not moving, who cares. The only time it even matters is on approach, and you can hear and feel the engines response. I never, ever, have looked down to see the thrust lever quadrant and wished there was movement. In fact, you really wouldn't see them move even if they did since you are focused looking out forward toward the outside world.

I'd like to see more of this "list" that goes on and on as well.
 
I'm not a bus guy, but I agree with ATN on this. You see crews in the sim ALL the time so focused on flying the plane that they ignore the aural warnings and flashing lights/bells.

As far as the trust levers go, my hand is on there during approach to "feel" what the motors are doing. Not having them move with the commanded thrust is just stupid.
 
PhilosopherPilot said:
Not having them move with the commanded thrust is just stupid.
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And that's the most frustrating part: it's just stupid. There is no logical reason to do it that way. It's pure stubbornness. Some non-pilot engineers came up with it, and Airbus now won't deviate from it, probably because they don't want to admit that Boeing has been right all these years criticizing their flawed philosophy.

The technology not only exists, it's incredibly light and cheap, to make the controls give tactile feedback. Hell, the joystick I used with Flight Sumulator 15 years ago had tactile feedback. I know Airbus sucks, but surely they can do as well as Microsoft!
 
PhilosopherPilot said:
I'm not a bus guy,
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Maybe you should've stopped there?

Seems to be the whole thrust lever feedback thing is a stupid point to make, as the airplane WITH the system is the one that just had a recent crash attributed to its automation.

I don't think, to date, anyone has stalled an Airbus and crashed it short of the numbers. There was that flyby often posted on here that went into the ground, but that was more about the guy who didn't push the power up until late in the game just before impact.
 
wheelsup said:
Maybe you should've stopped there?

Seems to be the whole thrust lever feedback thing is a stupid point to make, as the airplane WITH the system is the one that just had a recent crash attributed to its automation.
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I'm at a company that is primarily Airbus, and I've been in the 320 sim plenty of times, and I work with and am in meetings with 320 instructors all the time, so I'm not completely uninitiated.

I'm not saying it's causing crashes at all, but it does seem a negative human factors concept. Humans process information in many different ways, and the tactile feedback of a moving thrust lever is processed in a different way than looking for thrust changes visually. Obviously it's not causing crashes left and right, but I agree with ATN that it's a stupid design.

I don't think getting a type rating on the 320 will change my point of view on the lack of tactile feedback with the side stick and thrust levers.
 
seagull said:
Were it that simple! The lack of understanding of the system was also a consequence of Boeing not publishing anything about the matter until it was "discovered" during 787 flight test. The problem with just "turning it all off", which, you are correct, would have worked, is that it is only with the benefit of hindsight bias that it is clear that was needed.
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I"m going to have to call BS on that statement. Go back and re-read the thread where we discussed this before. It was known and it was trained. The only change that occurred in the B777 manual was a wording change that made it a little more clear. But, don't take my word for it, I've only been on the airplane since 2003 :rolleyes:.


TP
 
seagull said:
Well, in other OEM aircraft the autothrottles will NOT let you stall, and will always "wake up". There is no excuse for that. The fact that you can train to deal with the flaw does not change the fact that it is there. Further, if you have been used to flying aircraft that do NOT have this issue, you will not be expecting to encounter it, particularly when it is not really trained or demonstrated, which it was not at the time.
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You assume it was a "flaw". Again, go back and re-read some of the information that we have previously discussed. It was a conscious decision on the part of the designers to make it that way.

How did we not stall and crash all those old 727s, 737-200s, DC-9s, MD-80s, etc for decades? It beggars belief that one can say it's a design flaw to not have autothrottles that prevent stalls.

Would it be nice to have? Well, yes maybe, but it certainly isn't necessary as shown from over 1000 B777s flying for almost 20 years now.


TP
 
typhoonpilot said:
I"m going to have to call BS on that statement. Go back and re-read the thread where we discussed this before. It was known and it was trained. The only change that occurred in the B777 manual was a wording change that made it a little more clear. But, don't take my word for it, I've only been on the airplane since 2003 :rolleyes:.


TP
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Perhaps it was "known and trained" at YOUR company, but look at the NTSB report and you will see that for MOST operators it was MUCH more recent.
 
typhoonpilot said:
You assume it was a "flaw". Again, go back and re-read some of the information that we have previously discussed. It was a conscious decision on the part of the designers to make it that way.

How did we not stall and crash all those old 727s, 737-200s, DC-9s, MD-80s, etc for decades? It beggars belief that one can say it's a design flaw to not have autothrottles that prevent stalls.

Would it be nice to have? Well, yes maybe, but it certainly isn't necessary as shown from over 1000 B777s flying for almost 20 years now.


TP
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It was a conscious decision to maintain commonality with previous type designs, no more, no less. It was not in accordance with industry best practices.
 
seagull said:
I could get at least 50% of crews into that corner point. They only had to not look at their airspeed for about 8 seconds to get in the hole.
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8 seconds is a long time to not be scanning your airspeed during an approach. I mean, I probably shouldn't talk, I'm not a Boeing pilot, but why the hell aren't guys monitoring their airspeed on approach? That's like, I dunno, private pilot stuff! And OK, I understand that in the simulator, you can task saturate guys and get them to fixate until they auger in or whatever, but let's be serious, that's why we have the stabilized approach concept, that's why we have specific "gates" we fly through, as a pilot descends below 500' AGL, he or she should be thinking, "OK, I'm lined up on the proper runway, I'm properly configured, I'm stabilized on-speed, gear's down, sink-rate's good, I'm cleared to land." Whether or not there are callouts for this sort of thing, this is what a pilot should be thinking. It's really not that much to ask, it's only 6 things to think about. Here if that's too hard, I've even made a mnemonic for this:

Super C
Speed is stable at ref
Undercarriage is down and locked
Proper Configuration for landing
Excessive Sink Rate?
Right Runway is Right there
Cleared to land

At 1000fpm (which is probably an excessive sink rate on final in a Boeing, I don't know), and assuming the latest you can abort a landing is 200' AGL without hitting the ground (again I don't know), that gives you 18 seconds to figure out that something wasn't right. On the flip side, if your sink rate is less because you're dragging it in 30 kts under Vref, it should give you plenty of time to go, "uhhh, something's not right here, time to go around."

I dunno about this accident, I mean, I'm not a boeing pilot, and this most certainly could happen to me if I have a bad day, but blaming this on the design of the airplane or on the training department seems to be no-bueno for me. If I'm approaching the ground, and my speed or sink rate aren't correct, I go around. A go-around should be a conditioned response, like windshear, or a terrain alert.
 
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