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This is such an ignorant post I can't believe it. It appears you've never actually had an airplane's controls in your hands.
1) Fly-by-wire isn't what you think it is. It simply means there are no mechanical linkages.
2) Airbus' computer-over-human approach is no panacea and it has resulted in numerous near-disasters, one of the most recent ones.
3) Even Airbus isn't religious about this approach. Read up on Alternate Law and Direct Law.
4) Had Sully not maneuvered USAirways 1549, it'd have landed in the middle of housing.
5) Water landings require you to do a flare & float to stall just feet above the water level to minimize airspeed. If he had not done this, the airplane could have easily smashed itself apart, since an A320 power-off glide rate of descent is around 1500 fpm. Water isn't soft at these kinds of speeds you know.

Simply falling on this switch wouldnt cause it to change positions - it requires a deliberate act to do so, the switch requires a certain force to pull up and then move to one position or another, its not like accidentally changing channels on your TV because you sat on the remote.

I can believe this. But what if, instead of falling against the switch, the copilot, recognizing that he was about to pass out (e.g. recognizing symptoms of an impending stroke), intentionally attempted to move the switch to the "unlocked" postion (to make it easier for the captain to get into the cockpit quickly)? Due to a combination of confusion, physical incapacitation, and infamiliarity with a probably rarely-used control, he could conceivably have turned the switch to the wrong position even while he was attempting to do what he thought would be the best possible action.

Also, there is no button or switch he could have fallen on which would have caused the gradual descent that we know the aircraft took. Changing the auto pilot altimeter requires you to use a dial and then confirm the change in two separate actions. Any interaction with the side stick would require the auto pilot to be off, which would mean we should have seen a lot of other, large movements in the aircrafts path, which are completely missing from the telemetry we have at the moment.

The few commands that we see in the telemetry (and by telemetry I mean the transponder tracks, which cover speed, height and directional changes) indicate that the aircraft was under either the control of the pilot or the autopilot for the entire duration of the descent.

As far as I can tell, this is nonsense. Under "normal law" in an Airbus autopilot system, sufficient pressure on the control stick will override the autopilot system. For downward pitch, the autopilot system will allow up to 15 degrees of downward pitch to be commanded without removing the autopilot system from "normal law"; other autopilot functions will continue to function normally. I'm not sure what the exact result of 15 degrees of downward pitch would be, but I'm pretty sure it would be a rapid but controlled descent—exactly what the telemetry shows.

Carluva are you a god-damned terrorist or terrorist apologist? The co-pilot would have been strapped into their seat in the cockpit and if feeling faint would not have been able to get out of the seat and reach the door lock switch which would have allowed the pilot to re-enter in its default state anyway. You are as stupid as the Americans who voted for Mr. Hope and Change. The pilot and co-pilot should never leave the flight deck under any circumstances.

Simply falling on this switch wouldnt cause it to change positions - it requires a deliberate act to do so, the switch requires a certain force to pull up and then move to one position or another, its not like accidentally changing channels on your TV because you sat on the remote.

I can believe this. But what if, instead of falling against the switch, the copilot, recognizing that he was about to pass out (e.g. recognizing symptoms of an impending stroke), intentionally attempted to move the switch to the "unlocked" postion (to make it easier for the captain to get into the cockpit quickly)? Due to a combination of confusion, physical incapacitation, and infamiliarity with a probably rarely-used control, he could conceivably have turned the switch to the wrong position even while he was attempting to do what he thought would be the best possible action.

Also, there is no button or switch he could have fallen on which would have caused the gradual descent that we know the aircraft took. Changing the auto pilot altimeter requires you to use a dial and then confirm the change in two separate actions. Any interaction with the side stick would require the auto pilot to be off, which would mean we should have seen a lot of other, large movements in the aircrafts path, which are completely missing from the telemetry we have at the moment.

The few commands that we see in the telemetry (and by telemetry I mean the transponder tracks, which cover speed, height and directional changes) indicate that the aircraft was under either the control of the pilot or the autopilot for the entire duration of the descent.

As far as I can tell, this is nonsense. Under "normal law" in an Airbus autopilot system, sufficient pressure on the control stick will override the autopilot system. For downward pitch, the autopilot system will allow up to 15 degrees of downward pitch to be commanded without removing the autopilot system from "normal law"; other autopilot functions will continue to function normally. I'm not sure what the exact result of 15 degrees of downward pitch would be, but I'm pretty sure it would be a rapid but controlled descent—exactly what the telemetry shows.

the critical information relating to the flight situation of the aircraft was being withheld by the "smart" cockpit

The pilots were challenged by degraded systems: no air data meant they had no information about airspeed, vertical speed or altitude. It was attitude only during night IMC. No information was "withheld", per say, some simply wasn't available to them. They were all trained to standards, including stalls, and alternate law. Alternate law means that most protections are lost: pitch and roll limits, overspeed and stall prevention- you cannot stall newer Airbus in normal law, it won't let you. The aircraft still "flies" the same way. Boeing's cockpits are smart too, but are most definatley not immune to failures and connected yokes is not Here's a summary of Airbus flight control laws: http://www.airbusdriver.net/airbus_fltlaws.htm

If the former is true, what airline should I be flying on?

Like picking a surgeon or hospital, pick an airline that has quality training and experienced pilots. I would suspect that AirFrance has revisited their stall training for the better. Low pilot pay usually indicates low experience and poor training. High paid executives is a meaningless metric.

...the lack of any angle of attack gauge, a stall warning that does not sound when the airplane is so stalled as to be falling from the sky, and the lack of something making an enormous deal about the switch from normal law to alternative law flight mode.

Boeing doesn't present AOA either- it is not deemed relevant anymore with advanced flight display systems. Stall warnings (derived from AOA) are considered relevant and they did receive stall warnings: "At around 2 h 11 min 42, the Captain re-entered the cockpit. During the following seconds, all of the recorded speeds became invalid and the stall warning stopped, after having sounded continuously for 54 seconds." As for alternate law, I suspect your view of it is overly complicated. Direct law, however, is much like flying a paper airplane. The pilots will always be advised of what flight law the aircraft is operating in. Nonetheless, to get into that state requires multiple failures of redundant systems. With out any electrical power, the airplane cannot be flown- battery only is a greater emergency than fire.

Regarding the dual sticks with a dual input light, the key problem is this: when would averaging the joystick inputs actually be desirable?

Never. Its meant to be one stick at a time- just as pilots are trained on yokes. If the other pilot is fighting me on a yoke, I am the aural warning: 'I have the controls". In an Airbus the computer is the warning. We still must communicate on either plane.

Do both pilots frequently fly at the same time and average it out?

Never intentionally. That's why the system alerts them aurally and with a red warning light which can't be canceled and won't go away until the dual input is resolved. Few th

Think what you want,

http://www.airbusdriver.net/airbus_fltlaws.htm

Direct Law:

Pilot control inputs are transmitted unmodified to the control surfaces, providing a direct relationship between sidestick and control surface.

Unfortunately, it is impossible to train airbus crew to fly the plane. Airbus autopilot has at least four different levels of automation called "laws" http://www.airbusdriver.net/airbus_fltlaws.htm. Each one is disengaged by autopilot itself, if necessary. Now, there is no way to manually switch between laws hence pilots can not learn them. On top of it, airbus flies differently so all their past experience is somewhat useless or even counterproductive. In a way, I know how to fly with my 150 hours better, than your typical airbus pilot. It is scary.

PF: Pilot flying.
PNF: Pilot NOT flying
TOGA: Take off / Go around power. Layman's terms, "firewalling it".
Normal Law: Sidestick commands load factor (ie, "G") and roll rate. High speed / low speed / bank angle / stall / load factor protection.
Alternate Law: Arrived in this state due to system degradation. Numerous causes. Not really an issue. Sidestick commands load factor, however, direct control of ailerons. No protection other than load factor and stability at high / low speeds. Aircraft can be stalled.
Direct Law (reference): Sidestick directly commands elevator and aileron position. Aircraft enters this law with gear down and autopilot disconnected.

Useful reference:
http://www.airbusdriver.net/airbus_fltlaws.htm

What it DOES show is that the article is rubbish. Airbus don't have "primary" and "secondary" computers. It also shows that Airbus can fly without the flight computers (if the computers fail the systems switch to alternate law as detailed here: http://www.airbusdriver.net/airbus_fltlaws.htm )

This page details just what the different "Laws" mean. Look at "Alternate Law" (which the Air France plane operated in when it crashed) and "Direct Law", as well as "Mechanical Backup". These kick in when the computers (remember, everything is multiply redundant) detect anomalies or outright fail or when the pilot specifically takes them offline. Essentially, AFAIK if the majority of a certain system dones't show the same data, that system is considered untrustworthy and disabled.

Of course if all relevant sensors fail in an identical way the computer will not compensate (unless the sensor data doesn't match what the heuristics expect based on other data)... but then again, when the instrument insists on showing the wrong data, would the polit be able to detect the situation and react fast enough? In order for, say, all altimeters failing and the computer not noticing a dive, not only would most of the altimeters have to show the same incorrect value, the tilt sensors would also have to fail, as well as pretty much everything else involved with telemetry. The only plausible scenario I could imagine would be the entire plane losing power. And in that case Airbuses revert to the mechanical backup controls.

Also, as far as I have heard, so far most of the crashes involving a pilot vs. autopilot scenario occurred because of pilot error (like accidentally telling the autopilot to abort a landing and then trying to force the plane down).

Looks like it will become a new trend to skip over the comments of an article when posting it on /.. The first 15 I found there seem to dismiss the article completely as a piece of... rubbish, with links to "why", like http://www.airbusdriver.net/airbus_fltlaws.htm

What you claim, is I think in extreme doubt. The airbus is 100% fly-by-wire. When everything is working correctly The airbus allows a pilot an envelope of operation. But it will not allow a pilot to stray outside that envelope. When sensor data is erroneous the envelope is erroneous.

Not quite sure. Airbus airplanes have three distinct FBW modes, called "laws." Depending on how you count, there are three or more of them. In Normal Law, it is as you say. The airplane won't let you go into a mach tuck, won't let you stall out by going too slow, won't let you apply the rudder too hard, has strong yaw dampering, etc.

When things go wrong, the control laws are designed to degrade gracefully. To my knowledge, the airbus does not give pilots the choice of flight laws, which is what you are complaining about. If multiple systems fail, the system goes into "alternate law" which provides speed safety and yaw dampering only. Note that in alternate law, any changes that the computer requests can be overriden by the pilot. If ADR systems fail, the speed safety, rudder travel limiter, etc. are also disabled. This means that the plane is being flown pretty much in "direct law" but with yaw dampering.

Additionally, in alternate law, if the plane enters an unusual attitude, flight laws degrade further.

If additional failures occur, the plane reverts to "direct law" which is supposed to be an equivalent to mechanical control over the airplane. In direct law, some manual/mechanical backup systems are actually used.

If all FBW systems fail, there are limited mechanical backups to the rudder and elevators.

Sourse: http://www.airbusdriver.net/airbus_fltlaws.htm

Yes, it is an annoying debate tactic but weak and relatively easy to recognize. Diligent readers can recognize this though, and the glaring errors often come painfully to light in the discussions.

Anyway, the Airbus systems have multiple levels of computer massaging of the pilot's input, called different "flight laws." Read up about it here:

Airbus flight laws

In the most direct law, yes, the system will still not allow you to do things like rip the rudder off the airplane (A300 was not FBW) or clearly overstress the aircraft and destroy the wings. This is a good thing -- of course, there is perhaps some imaginary situation where it would be better to destroy the aircraft to ameliorate some aspect of an impending crash, however, the vast majority (all ever recorded in an actual crash?) of inputs that can destroy aircraft are not intentional nor required. Also, the 'direct law' will allow a pilot to potentially overstress the aircraft in the event of computer failure or discordant input.

The role of conflicting pilot input is also well thought out (described in the link), and the airbus designers were aware of these (pseudo)philosophical objections to excessive computer control. I do not think there is much of a conflict among people familiar with the operation and implementation.

Summary states:

Boeing planes allow pilots to take over from computers during emergency situations, Airbus planes do not.

According to this link, the Airbus does, in fact, have a manual override mode.

Which would make the argument as presented a moot point.

Airbus uses a sidestick controller, not a yoke (nor a yolk). There is no direct connection between the stick and the aircraft control surfaces. For more info on the Airbus Flight Control Laws, check out: http://www.airbusdriver.net/airbus_fltlaws.htm According to the ACARS data, they were in ALT2, which corresponds to the "ABNORMAL ALTERNATE LAW w/o Speed Stability" in the referenced URL. Personally, I'll place a small bet on the bomb (or meteor), and a much larger one on the crew doing something stupid, coupled with the inherent instability of the aircraft.

Look at the bottom of this chart - as I understand it there is a last level of control that is manual. I really don't know - I'm just making a wag that's as good as any, which I point out up front.

Had this been a permanent failure of the air data computer, an airbus pilot has no way to override the aircraft's intentions and recover from the dive. An airbus pilot can only watch, as the airplane says, "No, really, I'm stalling, I have to hold the nose down and pick up airspeed!".

Uninformed poppycock.

Airbus aircraft can be switched to a mode called "Direct Law".

In that mode, the control surfaces correspond 1:1 with the stick.
http://www.airbusdriver.net/airbus_fltlaws.htm

There have been aircraft accidents where an Airbus aircraft has crashed in situations where a Boeing aircraft would have been flyable by a human pilot.

No, there haven't.

Your citation is conspicuously absent.

And please don't troll with the Habsheim crash, which would have ended same (worse) if you tried the same insane stunt with a Boeing 737.