Debris, Bodies Recovered From AirAsia Flight 8501 132
Searchers have found traces of the crashed AirAsia Flight 8501, which lost contact with ground controllers shortly after requesting a weather-related course change. Reuters reports that both debris and some passenger remains have been recovered off the coast of Borneo, in a search complicated by waves "up to three meters high." From the report:
About 30 ships and 21 aircraft from Indonesia, Australia, Malaysia, Singapore, South Korea and the United States have been involved in the search.
The plane, which did not issue a distress signal, disappeared after its pilot failed to get permission to fly higher to avoid bad weather because of heavy air traffic, officials said. It was travelling at 32,000 feet (9,753 metres) and had asked to fly at 38,000 feet, officials said earlier. Pilots and aviation experts said thunderstorms, and requests to gain altitude to avoid them, were not unusual in that area.
... Online discussion among pilots has centred on unconfirmed secondary radar data from Malaysia that suggested the aircraft was climbing at a speed of 353 knots, about 100 knots too slow, and that it might have stalled.
Re:Pilot Proof Airbus? (Score:5, Insightful)
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Re:Pilot Proof Airbus? (Score:5, Informative)
Re:Pilot Proof Airbus? (Score:5, Interesting)
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. 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, I can't help but think that synchronous flight controls a la Boeing jets would have at least partially mitigated this problem (the senior pilot would have seen very clearly that the junior pilot was pulling back constantly). IANAP (I am not a pilot), but nevertheless... anyway, back to our regular scheduled programming.
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Indeed, AF447 is one of many clear cases of blaming human pilots for being human. Humans are prone to make unfounded assumptions without checking them, and no amount of check lists or training will ever stop that. Another example was that the stall warning system blared loudly in the cockpit as soon as the pilot did the right thing and tried to fix the stall, whereas it was silent as long as the plane was deeply stalled.
Either way, an emergency on a plane which is flying on autopilot is a bit like unpausing
Re:Pilot Proof Airbus? (Score:5, Insightful)
The pilot did not try to fix the stall. He was pulling up all the time and even the dumbest student pilots know that that's the exact opposite of what to do in a stall. His (in)famous almost last words were "I've been at maxi-nose up for a while". For some reason that only he knows, he thought the plane was diving fast and that the instruments are wrong ("crazy speed" he said). In reality he first steered it above the plane's maximum service ceiling at which point the plane pretty much lost all its speed and subsequently fell down with a slight nose up pitch. The stall warning stopped when he pulled back because the plane slowed down even more and by design, the warning is not meant to be triggered when the plane lands and that was how low their speed was. A better system would of course somehow factor in altitude but then again, any pilot should know that something else than a stall recovery has happened if he's just pulled back. The saddest thing about the whole crash is that apart from the brief moment when the pitot tubes were frozen, there was nothing wrong with the aircraft. The tubes were heated so when they began working, all the pilots would've had to do was to trust their instruments. They had plenty of altitude to recover control of the aircraft and every instrument worked and every warning was correct. A display of shameful incompetence by Air France training.
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The stall warning stopped when he pulled back because the plane slowed down even more and by design, the warning is not meant to be triggered when the plane lands and that was how low their speed was.
All the bad human interface design decisions have reasonable technical explanations. That does not make them good design decisions.
If that stall warning had kept working, AF447 would likely not have crashed. If the autopilot had not panicked and disabled the normal computer control because of a single faulty sensor, AF447 would likely not have crashed. If the plane had synchronized sticks, the other pilot would likely have taken control and AF447 would likely not have crashed.
Yet all the blame is put on the
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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 P
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Even towards the end, there were stall warnings. They were being ignored because the other failures kept the crew busy.
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).
The autopilot did not panic. The Airbus had 3 pitot tubes and they all failed.
It has 2 pitot tubes and 1 failed. Apart from that the aircraft was in perfect condition. The failing pitot tube recovered during the fall, so all equipment worked correctly.
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.
The autopilot shut off and the computer put the plane into altern
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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 [bea.aero]. 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 [wikipedia.org]:
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 o
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I am not sure why you think the part you copied from the transcript contradicts what I said. 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.
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 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. Yet the computer system stuck in alternate law, encouraging the pilot to do the entirely wrong thing.
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.
It was p
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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 [wikipedia.org] 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 n
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The stall warnings happened continuously throughout the time until the condition was corrected. It was never corrected.
This is a factual bit we disagree about.
See e.g. Stall warning controversy haunts AF447 inquiry [flightglobal.com]
After 54s, the stall warning started cutting out because the airspeed approached zero.
While the stall alarm sounded continuously for 54s the captain, urgently called back from a rest break, re-entered the cockpit just as it ceased. The warnings then became intermittent, owing to A330 logic that cuts out the alarm if airspeeds become invalid
SNPL president Jean-Louis Barber said the pitot failure "constituted the tr
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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 [bea.aero] 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 profession
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They didn't alarm all the time but they didn't stop
You have a strange definition of stop.
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.
I do not know where you get the impression that we disagree about this. Of course they stalled because their speed was too low and the AoA was too high.
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You have a strange definition of stop.
Again I refer you to the transcript. From the initial stall warning at 2 hr 10 min, there are stall warnings in every minute. Then the plane crashed.
I do not know where you get the impression that we disagree about this. Of course they stalled because their speed was too low and the AoA was too high.
Your conclusions have been wrong about Air France 447 because you have been wrong about the facts. The conclusions of the BEA specifically contribute the accident to the pilots and a number of other factors including the pitot tube design. However, the failure of the pitot tubes should not have led to a crash by themselves. You seem to want blame everything els
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Did the crew acknowledge alternate law? I haven't read the entire CVR transcript but I was under the impression that they didn't. Or, at the very least, the PF (Bonin, the younger guy) didn't seem to know what it meant.
Even if the display shows inputs, it's a lot harder to pay attention to a display with a little dot waggling around on it than a big old yoke pushing into your nutsack, especially when you're on a turbulence roller coaster and trying to figure out twenty-three other issues at the same time.
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The autopilot should not be unable to make sense of the information it gets because of a single faulty sensor. This is the 21st century, computers can do better than that.
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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 [bea.aero] 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 o
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Really it is.
Stall
Stall
Stall
Then the captain returns: "Er what are you doing?"
Not an easily shaken man apparently. He had less than a minute before they hit the water at that point.
But even the inexperienced pilot wasn't that far off. He thought he had the speed, he just didn't know the airspeed was totally wrong.
Then when the plane was crashing, he didn't realize what was happening. Maybe he thought the other pilot was nuts for going into a dive?
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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..
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I can't help but think that synchronous flight controls a la Boeing jets would have at least partially mitigated this problem...
That, and a working angle of attack indicator would be most prudent to have on board. However, the accident is a result of a very common error, where a kind of 'tunnel vision' develops, and nobody remembers to fly the plane.
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...because a very junior pilot was pulling the stick back *the entire time* and the senior pilot did not realize this
The ECAM (electronic centralized aircraft monitor: http://en.wikipedia.org/wiki/Electronic_centralised_aircraft_monitor [wikipedia.org]) provides an aural alert to the pilots if both sticks are out of neutral. Further, the inputs are additive- one full up and the other full down is summed as zero. This is not to say they heard it- hearing is the first sense to diminish when under stress.
I can't help but think that synchronous flight controls a la Boeing jets would have at least partially mitigated this problem
That question has been debated ad nauseum. Still, Boeing have maintained the synchronous approach and Airbus have remained dual-independ
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throttle position is not indicative of actual throttle amount (electronic controls)
The autothrust system in my opinion is extremely well thought out. The thrust levers behave exactly like any other non- autothrottle system when it is disarmed or disengaged. They do not move with thrust changes when engaged, but if there is any doubt one can always operate manually. As for AF447, when they lost air data systems the thrust went to thrust lock until the levers were moved by the pilots: thrust was locked at last setting.
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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.
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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.
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. In fact, many were shocked at how early he took his break as usu
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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
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This, I watched a documentary about a crash a year ago. One instrument malfunctioned, the pilot then proceeded to ignore like 8 other instruments, and his cockpit window, and continue to slow down until he crashed and killed everyone. Pilot training has obvious gone way downhill, they are often less able to deal with instrument malfunctions than if we just put a simple non robust auto pilot in control.
Sounds a bit like Eastern Air Lines Flight 401 [wikipedia.org]. On that flight the auto-pilot was in the wrong mode. They thought the autopilot would maintain the current altitude, but it was in a mode that maintained whatever rate of climb/descent was input to the control yoke. The plane basically flew into the ground while everybody was trouble shooting a burned out light bulb.
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...as was the case of an airbus that crashed because only one axis of the autopilot switched off unexpectedly.
Sounds like this accident: http://en.wikipedia.org/wiki/Aeroflot_Flight_593 [wikipedia.org] Failure to understand the autopilots control wheel steering mode. Roll mode reverted to manual and pilots failed to recognize it.
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Statistically, 2014 is the year with fewest plane crashes since the era of mass aviation began. Two of those were (Boeing, not Airbus) 777s loaded with passengers, which skewed the passenger death statistics to a level that has not been seen for 10 years or so, but as more automation comes into aviation, the trend is definitely leading to fewer problems, not more, more so if you account for the fact that the number of flights and passengers i
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You imagine computers up to the task of flying in crowded airspace and bad weather?
Re:Pilot Proof Airbus? (Score:5, Insightful)
Re:Pilot Proof Airbus? (Score:5, Insightful)
no, that is not the case at the present time. Don't get your ideas about technology from sci-fi tv shows
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Dear Fanatic, actual pilots say otherwise, the automatic systems presently in use CAN'T handle the craft in many situations. sorry.
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Wrong, you are speaking of a future that hasn't happened yet. Real present day systems are limited, research before spewing.
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For military applications they don't even need to all that good. Just not pass out in high g.
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And your test pilot friends are out of work? No, they still fly planes? Oops, you lose.
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You're confused, having a computer in the system responding to throttle and yoke movements to move control surfaces is not what we're discussing here. The flesh bags are in the loop and your life as passenger depends on them; some occassional bad landings with body count prove the point
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Stall? (Score:2)
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I'm not anything close to an expert, but wouldn't a stall be easily recoverable at 32,000+ feet?
Depends what caused the stall. If the engines ingested a tremendous amount of hail and water and flamed out then the crew may not have been able to start them again. They could still have gotten out of the stall into a glide, but with no power there would have been nowhere to go...
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Re:Stall? (Score:4, Insightful)
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Re:Stall? (Score:4, Informative)
Modern Engines are designed to ingest tremendous amounts of water and still run.
A Qantas airliner suffered a catastrophic engine failure ad returned to the airport. After landing, the engine was still running and spewing fuel everywhere. They poured foam and water directly into the engine for 30 minutes before it finally quit running.
You can watch a documentary on it here. [youtube.com]
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Modern Engines are designed to ingest tremendous amounts of water and still run.
http://en.wikipedia.org/wiki/T... [wikipedia.org]
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1988 is hardly "modern" in the context of jet engines.
This, [wikipedia.org] is modern.
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At 38,000 feet the difference between overspeed and underspeed (stall) can be as little as 10-12 knots. Many airplanes behave similarly in both conditions however recovery procedures are very different. There have been a number of accidents due to pilots not being able to tell the difference. For more information see: https://en.wikipedia.org/wiki/Coffin_corner_%28aerodynamics%29
Re:Stall? (Score:5, Interesting)
Or a cumulonimbus (CB) cloud. Pilots are generally advised to stay 20 miles AWAY from storm clouds because of intense up and down drafts.
It's likely the pilot was trying to do that when denied by ATC - and towering CB can go up to the stratosphere (literally - it's why they get their anvil shape).
No plane can outfly the up or downdrafts which can be several thousand feet per minute. Fly into it and 32,000 feet can be gone in just a few minutes. Never mind wind shear which can basically rob an airplane of all airspeed.
Embedded CBs are even scarier.
Pilot has the Last Word (Score:2)
It should be noted that the Pilot is responsible for the safety of everyone on board and has the very last word on it.
Assuming that the pilot was trying to avoid a dangerous thunderstorm that he had reason to believe would imperil the aircraft and passengers, he could have and should have changed course and/or altitude and tell ATC to fuck off, but keep them apprised at the same time so they can move others out of the way.
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Declare the Emergency, advise ATC of your intentions, and they move everyone out of the way. That's the way it works.
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And he should have declared an Emergency if he thought the weather in front of him was dangerous.
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I have no doubt the FDR's will be found and I think the similarities between these two events is significant.
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I'm not anything close to an expert, but wouldn't a stall be easily recoverable at 32,000+ feet? If a plane fell from this altitude without any radio contact I would think it would be some kind of catastrophic structural or mechanical failure.
Base on the reports of the weather I've been reading, it was about as bad as it gets for turbulence. They suspect the craft got hit by multiple lightening strikes as well. I've been on a plane when lightening has struck it before and while not immediately dangerous it's like being inside a flashbulb going off. It's terrifying. I couldn't imagine it happening multiple times while getting thrown around by turbulence.
Imagine being on a roller-coaster, inside a paint shaker while someone repeated shown
Lufthansa had an incident which might be related. (Score:5, Informative)
http://www.aeroinside.com/item... [aeroinside.com]
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Yes, there is an Airworthiness Directive [caa.co.uk] (caution:pdf) about that little issue. For some some reason, Airbus won't give the pilots an angle of attack indicator either. It is one of the most basic and important things to know when flying a fixed wing aircraft.
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There was a very similar crash involving frozen/jammed angle-of-attack (AOA) sensors with another A320 back in 2008, XL Airways flight 888T:
https://en.wikipedia.org/wiki/... [wikipedia.org]
In this case it was caused by aircraft maintenance personnel not covering up the sensors properly when repainting the livery, causing paint-related or cleaning chemicals to fill the gaps inside the AOA sensor housing and later freeze in-place once the aircraft was airborne - which caused confusion among the pilots when the aircraft's fli
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Correction: I should say "similar incident", not "crash", sorry (although the XL888T flight was a crash).
cnn.slashdot.org (Score:2)
daytime crash? (Score:2)
This of course assumes that the problem was a loss of attitude control due to instrumen
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What I find somewhat puzzling is how this happened in daylight. In AF447 and others where pilots lost control or were confused by conflicting instrument readings, it was during night or poor visibility and they lost reference to the horizon. This was at 7am Singapore time, and although there were storm clouds, I would have thought that at least for some portion of the incident, the horizon would have been visible? This of course assumes that the problem was a loss of attitude control due to instruments.
They were likely in clouds (remember they were trying to avoid a thunderstorm.) They probably had extremely poor visibility.
West Caribbean crash was similar (Score:3)
This Air Asia plane was asking permission to climb to FL380 from FL310 in a storm. But as others have noted, Air Bus has issues with pitot tubes icing over and the flight control computers getting confused.
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Any pilot who can't recover from a stall in 10,000 vertical metres is not even worthy of the job description. It is incomprehensible. Even in zero visibility in a piece of video game garbage like an Airbus, he's got an altimeter, right?
Poor AirAsia (Score:1)
You gotta have just a little sympathy [twitter.com]...
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From what I've read, you're completely wrong. This crash broke an eighteen year perfect record of zero fatalities for this airline, and this particular airline (unlike many others in the region) does not do pay-to-fly.
what? (Score:2)
I thought climbing too quickly stalls an engine. Why would climbing slowly in denser air that can run the engines better cause it to stall? Any pilots know what they're talking about? (or do they mean it was going too slow while climbing as opposed to climbing at too low of a rate).
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I think that 353 knots refers to forward airspeed... meaning that more airspeed is required to climb without stalling... such speed might be appropriate for lower altitude, like a landing profile, but not for climbing while at altitude. I'm not a pilot though, this is just my understanding.
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Yes. A rate of climb at 353 kts (vertical speed) would mean reaching 30000 ft in about 50 seconds. Rate of climb is typically given in feet/minute (typical values up to +/- 5000 ft/min).
The thrust / power generated by the engines is used to overcome drag, accelerate, and climb. Normally, at higher speeds more power is needed to overcome drag, leaving less power to climb. Except when reducing speed so much that the lift generated no longer is sufficient, and the engine output is creating the remaining lift (
Comment removed (Score:5, Informative)
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there is compressor stall. [wikipedia.org] and the FAA does have air worthyness directives to cover specifically A320/321 aircraft regarding problems with compressor stall. Until they recover the flight data and cockpit voice recorders all of the information being put out there is speculative.
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"throw a frozen goose through it."
That will result in a sudden loss or significant reduction of power. The engine will not keep trucking.
The frozen goose test is about ensuring that the engine does not suffer an un-contained engine failure. That is, no shrapnel leaves the engine pod, where it can further damage the aircraft. I'm unaware of any modern turbo-fan engine that can survive a frozen goose and keep on trucking. (Severe hail can do the same thing). This is why (still) so many aircraft incidents
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Engines don't stall, wings do. If your wings aren't passing through the air fast enough or are at too high an angle of attack (or both) the airflow over them becomes turbulent and the amount of lift the wing generates drops abruptly.
In aircraft with straight wings that can result in you being screwed. Aircraft with swept wings are generally designed so that the inside, further forward part of the wing stalls first. That means that a stall drops the nose, lowering the angle of attack and increasing airspe
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Engines can stall, especially turbines, compressors etc. The mechanism for stalling a turbine is the same as stalling a wing, flow and pressure imbalances prevents the blades from pushing air. They have been known to stall in the past but it's painfully obvious when they do, they make a really loud bang repeatedly several times a second and start shaking the wing.
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PS: a speed in knots indicates airspeed, not climb rate. Climb rates are in feet per minute or, rarely, m/s.
Why do they want to climb? (Score:2)
It's probably not the (only) reason for the crash, but I don't understand why they want to climb in this situation. The Air France flight did the same IIRC.
They can't hope to outclimb a CB and at FL390, the difference between stall speed and VNE gets pretty damn small.
Maybe it was too late to do anything else, but then they really need to improve their weather forecast in the area.
I expect this to be evidence of a crash site (Score:3)
Re: (Score:3)
They are slaving in the Ice Mines of IO for the Zaranthians.
Re: (Score:2)
There was also the option of them continuing to recover nothing (ask Malaysian Airlines)