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Comment Re:Pilot Proof Airbus? (Score 1) 132

This is a factual bit we disagree about.

You can read in the transcript. The stall warnings never stopped. They didn't alarm all the time but they didn't stop. The plane eventually stalled because the pilots did not correct the problem. I refer you to the final report of the accident not the opinion of a pilot's union.

The aeroplane went into a sustained stall, signalled by the stall warning and strong buffet. Despite these persistent symptoms, the crew never understood that they were stalling and consequently never applied a recovery manoeuvre. The combination of the ergonomics of the warning design, the conditions in which airline pilots are trained and exposed to stalls during their professional training and the process of recurrent training does not generate the expected behaviour in any acceptable reliableway.

That is unless you want to argue with conclusions of the official report.

Do you really think you need to tell me what a stall is?

When you posted something factually incorrect about what a stall is, I expect you to admit that you posted factually incorrect information. I'm not a professional pilot but I know enough about aviation to know what a stall is. Stalling due to high speeds is unlikely especially when that was not the case in Air France 447. There were climbing; their air speed was not too high. They were stalling because their air speed was too low and the AoA was too high; they just didn't believe the warnings.

Yes, the stall happened because airspeed was too low. However, the stall warnings did the worst thing possible: turn off when airspeed is low and turn on when airspeed increases.

There were a number of contributing factors to this accident, but you seem desperate to dismiss that the fact that the pilots made errors that led to the crash and blame everything else. The computer did not "panic"; it did exactly what it was supposed to do. The stall warnings while intermittent did alert the pilots to the exact situation that caused the plane to crash. This was a recoverable situation, and the pilots did not apply the proper procedures: Establish initial control then deal with the situation. Instead the crew panicked not the computer.

More generally, the double failure of the planned procedural responses shows the limits of the current safety model. When crew action is expected, it is always supposed that they will be capable of initial control of the flight path and of a rapid diagnosis that will allow them to identify the correct entry in the dictionary of procedures.

Comment Re:Are people sick of the MPAA? (Score 1) 400

Agreed. I was talking to two couples a while back (an older couple and a younger couple who happened to be one of the children of the older). The older couple remarked that when their children were growing up they didn't go to the movie theater for almost 10 years on a date. So they didn't see many movies. It was a big deal to get a babysitter for a movie night, etc. The younger couple who have a child too said time commitments meant they didn't go to the movie theater much. The difference was the younger couple still watched movies while raising a child while the older did not. Streaming, Red Box rentals, Digital and physical purchases meant that they didn't miss out on any movies the younger couple wanted to watch; they could do it on their own time schedule.

Comment Re:Pilot Proof Airbus? (Score 1) 132

I am not sure why you think the part you copied from the transcript contradicts what I said. .

No you said that the stall warning stopped when the pilot pulled up (read above). That is not correct. The stall warnings happened continuously throughout the time until the condition was corrected. It was never corrected.

The stall warnings sounded multiple times, whenever airspeed got high enough (i.e. the pilot was doing the right thing) to make the system believe the readings

No that is also incorrect. Stall warnings are when there is not enough lift. Most of the time (and in this accident), this is when the airspeed is too low or the angle of attack is too high. Stalling at high speeds is possible but not in this case especially since the pilot was climbing not diving.

The pitot tubes were working correctly for the majority of the accident, precisely because there was no ice on them for the majority of the accident.

The pitot tubes were to be replaced per schedule because they had a tendency to ice up during flights. I point you to the wiki article on the flight as multiple incidents led to the replacement advisory.

Yet the computer system stuck in alternate law, encouraging the pilot to do the entirely wrong thing.

The computer did not get "stuck" in alternate law. The computer with conflicting airspeed readings goes to alternate law by design. This is basic flight (and computer system) protocols. As for "encouraging the pilot to do the entirely wrong thing", I don't know where you get this idea: The computer did not goad the pilots into climbing nor told them what to do. The computer realized it could not fly the plane according to its program and switched to alternate law giving the pilots full control of the aircraft. It is up to the pilots to fly manually (which they are supposed to be trained to do).

The problem is the pilots did not follow training or procedures. It may be an increasing problem as more pilots rely too much on autopilot. This has been identified as a trend in all airlines as more airlines are created with more flights and more planes. The US is also subject to this problem; however, the US has a larger pool of ex-military pilots who were trained to fly manually.

Comment Re:Are people sick of the MPAA? (Score 4, Interesting) 400

Not only the price has gone up; the experience has gone down. I do see movies now and then but I am selective where I see and which movie. I am fortunate to live within driving distance to a movie and dinner theater like Alamo Drafthouse or Studio Movie Grill. They are what I consider "adult" theaters (not porn) in that they bring back the experience of a movie for adults.
  • No one under 18 (unless it is a kid's event)
  • no talking
  • no texting
  • no arriving late
  • real food and alcohol served to you at your seat

In fact Alamo a few years back threw out a seemingly drunk individual for texting and turned it into a pre-movie PSA.

Comment Re:Pilot Proof Airbus? (Score 1) 132

Read the cockpit transcript. The stall warnings stopped whenever the crew member pulled the stick back and made the stall worse. (They stopped because the computer was programmed to treat the ridiculously low airspeed indications as instrument failures and disregard them).

I have. That's not what I read in the transcript. 2 h 10 min 03: Cavalry charge (autopilot disconnection warning)
2 h 10 min 10,4: SV: stall
. . .
2 h 10 min 13,0: SV stall
. . .
2 h 10 min 41,6: Weâ(TM)re in... yeah weâ(TM)re in climb
2 h 10 min 51,4: SV Stall
(for the next minute until 2 h 14 min 01,7 there are stall warnings)

It has 2 pitot tubes and 1 failed.

This is incorrect:

On 12 August 2009, Airbus issued three Mandatory Service Bulletins, requiring that all A330 and A340 aircraft be fitted with two Goodrich 0851HL pitot tubes and one Thales model C16195BA pitot (or alternatively three of the Goodrich pitots)

Apart from that the aircraft was in perfect condition. The failing pitot tube recovered during the fall, so all equipment worked correctly.

The pitot tubes failed because of icing. There would be no ice when they were recovered so "working correctly" isn't exactly true as the conditions of the accident were not in place when they were recovered.

The autopilot shut off and the computer put the plane into alternate law, where pilots are allowed to do stupid things like stall the plane. The computer had one perfectly working airspeed indicator to rely on, but instead it panicked.

Do you know what happens when one of the pitot tubes fails in these conditions? It give erratic readings. So the autopilot cannot determine which one of the 3 readings is correct. It's not "panicking" if it is meant to do that.

Comment Re:And who will watch it? (Score 1) 146

The North Korean people do have access to DVD players and computers. North Korea isn't in the stone ages when it comes to some technology as some people have access to cell phones. One of main problems has been a lack of enough food and totalitarian control of outside communication like the Internet . In this Frontline report, blackmarkets items include DVDs and thumb drives smuggled from China (24:20).

Comment Re:No group "owns" any day on the calendar. (Score 1) 681

Happy Holidays offends _me_ only because it is so damn generic and politically correct.

The point is to be generic. Personally I can't tell by looking at someone if they are Christian or Jewish or Hindu. Remember it is not "Happy Holiday" as Hannukah lasts 9 days, Pancha Ganapati lasts 5 days, and Kwanzaa lasts 7 days. It covers all bases.

So I think I will just go with "Have a merry Santa Claus Day and a happy new year" (Unless we don't want to offend people following other calender new years.)

Go right ahead. But the point is that someone deciding to say "Happy Holidays" instead is their choice.

Comment Re:Pilot Proof Airbus? (Score 1) 132

If that stall warning had kept working, AF447 would likely not have crashed.

Even towards the end, there were stall warnings. They were being ignored because the other failures kept the crew busy.

If the autopilot had not panicked and disabled the normal computer control because of a single faulty sensor, AF447 would likely not have crashed.

The autopilot did not panic. The Airbus had 3 pitot tubes and they all failed. Since the autopilot can no longer determine airspeed it cannot accurately compute throttle and altitude settings. So it shut off and alerted the pilots that it was shutting off; however, since the airspeed indicators failed this triggers other alarms.

If the plane had synchronized sticks, the other pilot would likely have taken control and AF447 would likely not have crashed.

My understanding is there is a procedure for emergencies. The Pilot Flying (PF) usually is the right-side pilot. The Pilot Not Flying (PNF) is the left-side and deals with the computer, instrumentation, etc while the PF flies. Now there are procedures for the PNF to take control by declaring like "Taking control" or "My aircraft". This alerts the PF to stop inputs and he acknowledges relinquishing control "You have control" or "your aircraft". That did not happen in this case. At best both pilots never communicated when the PNF should or would take over.

Synchronized sticks may have helped but the more distressing problem was a communications and training breakdown.

Comment Re:Pilot Proof Airbus? (Score 1) 132

From what remember a major breakdown in procedure was that the pilots didn't follow training to take control of the aircraft by setting at 85% thrust and 5 degrees first then trying other things if that didn't work.

NARRATOR: As they [simulator pilots] edge around the storm, Alder triggers the critical moment of Flight 447: he fails all three airspeed indicators.

SIMULATOR CO-PILOT: Okay, we have NAV ADR 1 fault. We have unreliable airspeed.

NARRATOR: The automatic flight control systems shut down.

SIMULATOR CO-PILOT: We're flying with no auto-pilot or auto-thrust.

SIMULATOR CAPTAIN: Okay. Autopilot's off. I have control.

SIMULATOR CO-PILOT: You have control.

NARRATOR: If their actual airspeed rises or falls by as little as 10 knots, they could suffer a catastrophic loss of control. But the pilot uses standard procedures, learned in training. He moves the throttle levers to set thrust at exactly 85 percent.

SIMULATOR CAPTAIN: And I'm selecting...I've got 85 percent set.

NARRATOR: Then, he raises the elevators to pitch the nose up at precisely five degrees. With engines at 85 percent power, and five degrees upward pitch, the aircraft should always settle at the same safe speed.

Comment Re:Pilot Proof Airbus? (Score 1) 132

With the pitot tubes covered in ice the airspeed would have been completely wrong. An issue was the throttle position is not true to the actual throttle amount. On the Airbus, it has autothrust so that the throttle itself doesn't move but the computer changes the speed according to what is needed.

JOHN COX: The thrust levers themselves, the throttles, don't move. Unlike some other airplanes, where you can feel the throttle in your hand moving, with Airbus aircraft, that throttle doesn't move with auto-thrust engaged, so you have to look at specific engine power indications.

When the auto-pilot shut off, it didn't reset the throttle amount to the position, it stayed where the setting had been by autothrust.

NARRATOR: The power indication is displayed here, on the central control panel. But if auto-thrust switches off while the engines are in low power, the crew might lose track of the low thrust level.

JOHN COX: If you're very task-saturated, your concentration's going to be directly in front of you. What's the power output of the engines? You're going to have to physically turn your attention and look to the center console area..

This is not going to be done as frequently as looking at, at the things right in front of you. It, it's certainly going to be in the scan; the question is, "How often?".

NARRATOR: The aircraft is now nearer the lower end of its safe speed range. But overloaded by fault warnings, the crew might not realize they need to increase power..

Comment Re:Pilot Proof Airbus? (Score 1) 132

That's not how I understand it, based on the translation of the cockpit recording. The captain was allowed to take a break whenever he wanted and unfortunately he chose the time right before the plane entered a storm that led to the air speed tubes freezing over. I wouldn't call it "scheduled" as that sort of implies something like "At exactly 3 hours into the flight the captain will take a break" when the timing of the break was up to him.

By scheduled I meant that all pilots are required to take a break during these long flights which explains why he was not in the cabin when the initial alarms went off. He returned to the cabin after a few minutes of the initial alarm.

In fact, many were shocked at how early he took his break as usually the captain takes a break much later in the flight. But they didn't know for a while that he was apparently flying on only 1 hour of sleep as he had sleeping problems in his hotel, so that must have made him want to take his break early.

The point isn't that when he took his break or how far into the flight or for what reasons. Before he took the break, everything seemed under control so he took his break.

The cockpit recording seems to indicate the senior co-pilot not helping as much as you might think. He did help some, but it seemed clear that he kept deferring in judgement to the guy flying the plane, which was a fatal mistake in hindsight.

In my recollection about procedure, it is the right-side pilot that flies while the left-side deals with other factors during an emergency like this. The left-side pilot was trying to figure out the alarms and what to do about them so that both pilots are not doing the same things.

Some aviation experts are speculating that the rapid expansion of budget airlines in Asia has led to training shortages and if this ends up being a similar accident to AF447 where an improperly trained pilot inadvertently puts the plane into a stall, all I can say is that this wasn't supposed to happen again. After AF447 the airlines were supposed to train specifically to prevent that kind of thing from happening again

One of the problems identified was that the crew did not follow proper procedures and ignored stall warnings as they assumed they could not trust that warning over the other alarms.

Comment Re:Pilot Proof Airbus? (Score 2) 132

It's interesting... most of the expert opinions I have heard say that the asynchronous nature of Airbus sidesticks was *not* to blame, and that the crash would not have happened if the pilots were properly communicating as per Cockpit Resource Management protocol.

There's blame and there are contributing factors. Accidents like these are normally a series of failures that leads to the accident.

However, when you consider that the crash happened basically because a very junior pilot was pulling the stick back *the entire time* and the senior pilot did not realize this,

In the Airbus, it is not a flight stick. It is a joystick. If I remember correctly this picture demonstrates the configuration of the joystick. If I remember correctly the flying pilot was in the right-side seat so it was not evident to the other pilot what he doing with the controls. Second, the other pilot isn't having scones and coffee while all of this is happening. The other pilot was dealing with a plethora of warnings and failures and trying to diagnose them all. Communication did break down.

From the transcript Around 2 hr 12 min 32 sec:
Left side pilot: "so go down "
Captain: "No you climb there "
Captain: "You’re climbing"
Right side pilot: "I’m climbing okay so we’re going down"
2 hr 13 min 40 sec
Right side pilot: "But I’ve been at maxi nose-up for a while"
Captain: "no no no don’t climb"
Left side pilot: "so go down "

From my interpretation, it appears the left is telling the right to dive and the captain is simply alerting the right that he is climbing. The right has misunderstood and is still pulling not pushing. In the second set, the left and captain realize that the right has been pulling the entire time. But it's too late.

Comment Re:Pilot Proof Airbus? (Score 5, Informative) 132

Well in the case of Air France 447, an additional factor was that the least experienced pilot was in control of the aircraft at the time. Another factor was the joystick control was not visible to the other pilot and the throttle position is not indicative of actual throttle amount (electronic controls). The more experienced pilot was trying to deal with the all the computer failures and assumed that the flying pilot was diving when he was trying to climb. It wasn't until the captain got back into the cockpit (he was on a scheduled sleep break) that the senior pilots realized the plane was trying to climb. They tried to get the plane to dive but it appears the plane stalled and crashed into the ocean before they could do that.

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