Airbus a320

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Old 03-24-15, 01:36 PM
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Airbus a320

Airbus just put this out last December, kind of scary to me.

12-09-2014

An occurrence was reported where an Airbus A321 aeroplane encountered a blockage of two Angle Of Attack (AOA) probes during climb, leading to activation of the Alpha Protection (Alpha Prot) while the Mach number increased. The flight crew managed to regain full control and the flight landed uneventfully.

When Alpha Prot is activated due to blocked AOA probes, the flight control laws order a continuous nose down pitch rate that, in a worst case scenario, cannot be stopped with backward sidestick inputs, even in the full backward position.

If the Mach number increases during a nose down order, the AOA value of the Alpha Prot will continue to decrease. As a result, the flight control laws will continue to order a nose down pitch rate, even if the speed is above minimum selectable speed, known as VLS.

This condition, if not corrected, could result in loss of control of the aeroplane.

http://ad.easa.europa.eu/blob/easa_a..._2014-0266-E_1
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Could be just a coincidence but it sure sounds similar to me except for the ending. I'd sure hate to be riding in the pointy end. Terrible.
 
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Old 03-24-15, 03:22 PM
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Interesting. The corrective action in the airworthiness directive is procedural rather than a hardware fix; a matter of which switches to flip during the uncommanded nose down condition. I'm guessing they'll be checking the airlines' aircrew training and flight manuals to see if they have the updates annotated. Also if the pilots' latest simulator time included the procedure.
 
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Old 03-24-15, 07:01 PM
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I guess what bothers me is if the computer thinks the pilot is an idiot the pilot loses and we all know a computer never screws up.

Like that plane a while back that was in a thunderstorm and the pitot tubes froze and they dropped like a rock into the ocean. Think about it....it's dark out, your instruments say you're doing fine but in reality you're about to stall and they did. How the heck do you know how fast you're going, you can't look out the window and watch the trees go by?

Huge mess this one is, interesting what they find out.
 
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Old 03-24-15, 07:04 PM
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Many are not fans of the Airbus style of heavy handed computer flight controls but I think it is the way of the future. Modern designs keep pushing the center of gravity further aft for fuel economy and have to rely more and more on the computers to keep it all under control. Unfortunately it places even more importance on the pitot static systems and angle of attack sensors. It's great when most everything is working but when thing go wrong it can present the flight crew with a daunting and non-intuitive task.
 
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Old 03-24-15, 07:20 PM
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Could also lead to all new avenues for terrorists to do their dirty work by hacking in. Give me hydro-mechanical flight controls any day.

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Old 03-25-15, 05:07 PM
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Like that plane a while back that was in a thunderstorm and the pitot tubes froze and they dropped like a rock into the ocean. Think about it....it's dark out, your instruments say you're doing fine but in reality you're about to stall and they did. How the heck do you know how fast you're going, you can't look out the window and watch the trees go by?
It was the pilots that caused the plane to crash into the ocean, not the computer.
 
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Old 03-26-15, 03:48 PM
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An there it is. The co-pilot crashed it on purpose.
 
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Old 03-26-15, 04:37 PM
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Yes indeed, he sure did. I had hoped the passengers didn't realize what was going on but I guess that isn't the case.
 
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Old 03-26-15, 04:45 PM
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Another scenario would be a mechanical problem the computer tried to "fix". Going into a stall, the computer would nose the plane down to gain air. There was just so much "air" between the plane and the mountain. The co-pilot trying to handle the situation by pulling back on the stick would have shortly tunnel visioned him to where nothing else mattered, even the pilot beating on the door. Until they find the data card in the last black box, I guess we'll be on hold for the actual cause.
 
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Old 03-27-15, 08:14 AM
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I am quite surprised that a cause has been "declared" as fact and so much detail is being put out so soon after the accident. At this point I would classify it as not much more than speculation. It might be correct speculation but I will withhold judgement until the accident investigators have had the time to quietly do their work. It is already tragic for the copilots family but it will be doubly so if it turns out there was some other problem and he was working to save the aircraft.

---
On a somewhat unrelated note. The news media is quick to point out that the European regulations allow only one person in the cockpit which is not permitted in the US. I have not heard anyone mention that many US pilots are armed (note that flight attendants are not armed). What use would a flight attendant standing in the cockpit be with an armed pilot intent on something evil?
 
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Old 03-27-15, 03:13 PM
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I agree, Dane. It seems the latest news is saying the autopilot was set to a low altitude, and thus the crash. The data card for the second black box (FDR) hasn't been found, so where are the news media getting this confirmation??
 
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Old 03-27-15, 04:57 PM
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Guess #2

I am quite surprised that a cause has been "declared" as fact and so much detail is being put out so soon after the accident.
You and a whole lot of other people.


...so where are the news media getting this confirmation??
It was the French prosecutor, I think that was his title, that said it was a deliberate act by the co-pilot although they haven't given their reasoning so far as long as I know. They had to have something concrete to make that statement so fast but what is it?

Well, I'm here to tell you, I think.

If you watch the short video I posted at the end of Ray's thread concerning the door locking system you will see.

1) no way was the nut case in the cockpit going to unlock the door for the pilot.

2) pilot enters code and buzzer sounds in the cockpit for 30 seconds and the door unlocks with no action from the cockpit crew.

That's the kicker...no action from the cockpit crew. This is where my brain kicks in because it isn't explained anywhere.

Buzzer sounds to begin 30 second unlock procedure, nut job doesn't want him in so he moves the lever to lock for 5 minutes. Haven't heard this anywhere but I'd guess the buzzer quits when he again locks the door, say 10 seconds after it begins. Bingo.... this is heard on the CVR. He wasn't incapacitated and intentionally again locked the pilot out. BOOM. Case closed.

Five bucks anyone?
 
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Old 03-27-15, 05:32 PM
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This is from the French prosecutor. They could hear the pilot knock on the door to get back in. Politely at first and then more aggressively. They said it sounded like he was trying to break the door down. They could also hear the breathing of the co-pilot as being normal throughout the event. Right before impact they could hear the screams of the passengers.

I find this evidence to be very strong, myself. After searching the residence of the co-pilot, they found evidence that he was being treated for depression/anxiety and notes from his doctor excusing him from work.
 
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Old 03-27-15, 06:28 PM
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I have not heard anyone mention that many US pilots are armed (note that flight attendants are not armed). What use would a flight attendant standing in the cockpit be with an armed pilot intent on something evil?
Which is good reason to question whether the post 9-11 precautions haven't created as much of a danger as they are suppose to prevent. But as yet I haven't heard the precautions questioned. I think they should be closely reviewed.
 
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Old 03-27-15, 07:02 PM
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But as yet I haven't heard the precautions questioned.
I guess you're not as intrigued by this as I am. I've watched hours and hours on different channels today and a lot of people have brought this up. What to do seems the main question.


Right before impact they could hear the screams of the passengers.
Yes, how awful. At least they didn't feel a thing I'm sure.
 
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Old 03-27-15, 07:15 PM
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What use would a flight attendant standing in the cockpit be with an armed pilot intent on something evil?
Many mentally deranged people are just fine as long as they are around others in normal conversation. It's those moments alone that can sometimes set them off...(ask my neighbors..j/k). And those pilots that do request to have a firearm (a very small minority I imagine) probably undergo an intensive screening as well as training. And if someone was authorized, and unlocked the box where it's stored, at least the attendant would have a chance to talk with them.

I imagine it's quite different to be looking someone in the eyes when you plan the deed.

Other than troops in combat or under severe stress, I don't think I've heard of any professional carrier of a firearm using it for nefarious purposes, though I'm sure the reports are out there.
 
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Old 03-28-15, 04:46 AM
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Other than troops in combat or under severe stress, I don't think I've heard of any professional carrier of a firearm using it for nefarious purposes, though I'm sure the reports are out there.
Happens a lot with cops. And I'm not talking about on duty incidences.
 
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