Air France jet missing

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Procede
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Re: Air France jet missing

Postby Procede » Tue May 24, 2011 10:16 am

That's not the same.
No, it's even worse: The autopilot / throttle did not even disconnect, which would have given a clear warning to the pilots.
The unreliable airspeed did.
I'm thinking a bit further back: What event caused such degradation of systems that airspeed became unreliable and the aircraft reverted to alternate law? A frozen pitot tube, hail the size of golf balls or damage to the horizontal tail?

As far as I know deep stall is only an issue with T-tails. Even if they did stall, why couldn't they recover?

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Re: Air France jet missing

Postby 666 » Tue May 24, 2011 10:21 am

WSJ blames pilot training.
Black Boxes Point to Pilot Error

The pilots of an Air France jet that crashed into the Atlantic Ocean two years ago apparently became distracted with faulty airspeed indicators and failed to properly deal with other vital systems, including adjusting engine thrust, according to people familiar with preliminary findings from the plane's recorders.

The final moments inside the cockpit of the twin-engine Airbus A330, these people said, indicate the pilots seemingly were confused by alarms they received from various automated flight-control systems as the plane passed through some turbulence typical on the route from Rio de Janeiro to Paris. They also faced unexpectedly heavy icing at 35,000 feet. Such icing is renowned for making airspeed-indicators and other external sensors unreliable.

Ultimately, despite the fact that primary cockpit displays functioned normally, the crew failed to follow standard procedures to maintain or increase thrust and keep the aircraft's nose level, while trouble-shooting and waiting for the airspeed sensors and related functions to return to normal, according to these people.

Slated to be disclosed by investigators on Friday, the sequence of events captured on the recorders is expected to highlight that the jet slowed dangerously shortly after the autopilot disconnected. The pilots almost immediately faced the beginning of what became a series of automation failures or disconnects related to problems with the plane's airspeed sensors, these people said.

The crew methodically tried to respond to the warnings, according to people familiar with the probe, but apparently had difficulty sorting out the warning messages, chimes and other cues while also keeping close track of essential displays showing engine power and aircraft trajectory.

Spokesmen for Air France, a unit of Air France-KLM, and Airbus, a unit of European Aeronautic Defence & Space Co., have declined to comment on any details of the investigation. Airbus last week, however, issued a bulletin reassuring airlines that the preliminary readout of the recorders hasn't prompted any "immediate recommendation" regarding the safety of the global A330 fleet. French investigators, who gave the green light for that statement, also have said their preliminary findings don't highlight any major system failures or malfunctions that could have caused the fatal dive.

The Air France pilots were never trained to handle precisely such an emergency, according to safety experts and a previous report by France's Bureau d'Enquetes et d'Analyses, which is heading up the investigation. All 228 people aboard Flight 447 died in the accident.

The senior captain, Marc Dubois, appears to have been on a routine rest break in the cabin when the fatal chain of events started, according to safety experts familiar with the details, but the cockpit-voice recorder suggests he may have rushed back to the cockpit to join the other two Flight 447 pilots.

Though Friday's announcement won't provide final conclusions or specific causes, investigators believe Air France didn't train its pilots to cope with such automation problems in conjunction with a high-altitude aerodynamic stall, an emergency when the wings lose lift and the plane quickly becomes uncontrollable. Since the crash, Airbus and a number carriers, including Air France, have emphasized such training.

According to a report issued by French investigators in November 2009, Airbus identified 32 instances involving similar model jetliners between 2003 and 2009 in which external speed probes, known as pitot tubes, suffered ice buildup at high altitude and caused "erroneous air speed indications." Over the years, the same models also suffered numerous failures of external temperature-sensors because of icing. Both issues were known to Air France.

Most of the incidents with speed sensors involved probes similar to those on the A330 that crashed. Many were on Air France planes, according to the BEA report.

Friday's update follows sniping between senior officials of Air France and Airbus, usually close corporate allies, who in this case have tried to shift the blame for the accident to each other.

Air France began addressing problems with its pitot tubes almost a year before the crash. Amid several incidents in which air crews lost speed indication at high altitude during 2008, Air France reported the icing problems to Airbus. The two companies discussed solutions and Airbus talked to its supplier.

In April 2009, roughly 45 days before the crash, Airbus proposed that Air France swap out its pitot tubes for a different model believed to be less prone to icing, according to the BEA report. Air France began the work on April 27, 2009, and it received the first batch of new pitot tubes six days before the crash. The plane that crashed hadn't yet received the new equipment.

According to the 2009 report published by investigators after the crash, experts examined 13 other incidents of airspeed-sensor malfunctions on Airbus widebody jets at cruise altitudes. During most of those global incidents—none of which resulted in a crash—both the autopilots and automated engine-thrust systems disconnected on their own, and it took many of the flight crews up to a minute to manually adjust engine thrust.

The earlier report found that pilots in nine of those 13 events received warnings of an impending stall. And in a finding that may have particular relevance to the upcoming update, accident investigators in 2009 also concluded that when airspeed-sensor malfunctions kick off automated thrust controls, "the absence of appropriate manual adjustments" to engines "can present a risk" of a mismatch between power settings and the jet's orientation in the air.

Investigators began focusing on pitot problems from the start, because Flight 447's automated maintenance system broadcast 21 separate messages related to such malfunctions during roughly the last four minutes of the fatal flight. But the final report, which may not be released until 2012, also is expected to delve deeper into how European air-safety regulators dealt with persistent reports of pitot-tube icing prior to the crash.

The previous interim report indicated that in late March 2009, less than three months before the crash, European aviation regulators decided that the string of pitot-icing problems on widebody Airbus models wasn't serious enough to require mandatory replacement of pitot tubes.

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Re: Air France jet missing

Postby OldSowBreath » Tue May 24, 2011 4:25 pm

AS I've said all along, "Pitot Error".

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Re: Air France jet missing

Postby Gabriel » Tue May 24, 2011 9:57 pm

That's not the same.
No, it's even worse: The autopilot / throttle did not even disconnect, which would have given a clear warning to the pilots.
The PRIMARY FLIGHT display showed an obviously erroneous radio-altitude of -8 ft for some 20 minutes. The procedures say that in that case the A/T must be disconnected for the approach. They noted the error, but didn't follow the procedures. The approach was NOT STABILIZED neither at 1000ft nor at 500ft, but they didn't abort the approach as required by the procedure. At one point the thrust levers commanded RETARD, and Flight Mode Annunciator, displayed in the PRIMARY FLIGHT display, showed that and kept showing that for a couple dozens of seconds. The airspeed, also shown in the PRIMARY FLIGHT display, descended below Vref, and kept descending for several seconds. At the same time, the pitch attitude, also displayed in the PRIMARY FLIGHT display was increasing to values well above the typical (and even the non-typical) ones for an approach, again for several seconds. The glide slope indicator, also displayed in the PRIMARY FLIGHT display showed the plane descending below the glide slope for a few seconds, before the stick shaker activated and the AP disengaged.

Pause. You know that, in PRIMARY FLIGHT display, the words PRIMARY FLIGHT are there for something. Ask any pilot, even flyboy, what are the most important tasks of the pilot flying during an ILS approach in IMC on autopilot and they'll tell you "to monitor the autopilot mode, the speed, the attitude and the ILS", all of which, not just by chance, are displayed in the PRIMARY FLIGHT display. You had three required crewmembers in that cockpit, and nobody was seriously paying attention to the PRIMARY FLIGHT display, and during an ILS approach in IMC on AP that means that nobody was flying the plane.

Finally, upon the sitckshaker, the FO, who was the pilot flying (sort of), correctly reduced the AoA and increased thrust, and that was effective to initially stop the stickshaker, but incorrectly didn't disengage the AT, which is one of the steps of the stall recovery procedure. A second later the captain called "my plane. The FO removed his hands from the yoke and thrust levers, and the captain put his on the yoke alone. Because the AT was still engaged and in RETARD, it brought the throttles back to idle. By when the captain decided to put his hands in the throttle it was already too late. He did set max thrust, but the plane struck the ground as the engines were still spooling up.

So you have an event that started several minutes before the landing, with the pilots not following the procedure for an approach with a failed radioaltimeter that they were aware of. Then nobody flew the plane during the ILS in IMC, and then they botched the stall recovery. They had plenty of opportunities to and time to avoid, detect, and correct, and they failed at them all.

Compare that with an unreliable speed event where there are a dozen of system failures, error messages, warnings, and the plane changing from AP and AT to manual fight, with a control law that has just changed and that left the plane with no envelope protections, all at the same second.
The unreliable airspeed did.
I'm thinking a bit further back: What event caused such degradation of systems that airspeed became unreliable and the aircraft reverted to alternate law? A frozen pitot tube, hail the size of golf balls or damage to the horizontal tail?
Something like that. The strongest theory by now is ingestion of ice crystals.
As far as I know deep stall is only an issue with T-tails. Even if they did stall, why couldn't they recover?
This remains to be answered. We'll have more info on Friday.

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Re: Air France jet missing

Postby Procede » Fri May 27, 2011 12:19 pm

New briefing by BEA: http://www.bea.aero/fr/enquetes/vol.af. ... 011.en.pdf
:arrow: The composition of the crew was in accordance with the operator’s procedures.
:arrow: At the time of the event, the weight and balance of the airplane were within the operational limits.
:arrow: At the time of the event, the two co-pilots were seated in the cockpit and the Captain was resting. The latter returned to the cockpit about 1 min 30 after the disengagement of the autopilot.
:arrow: There was an inconsistency between the speeds displayed on the left side and the integrated standby instrument system (ISIS). This lasted for less than one minute.
:arrow: :arrow:After the autopilot disengagement:
:arrow: :arrow:the airplane climbed to 38,000 ft,
:arrow: :arrow:the stall warning was triggered and the airplane stalled,
:arrow: :arrow:the inputs made by the PF were mainly nose-up,
:arrow: :arrow:the descent lasted 3 min 30, during which the airplane remained stalled. The angle of attack increased and remained above 35 degrees,
:arrow: :arrow:the engines were operating and always responded to crew commands.
:arrow: The last recorded values were a pitch attitude of 16.2 degrees nose-up, a roll angle of 5.3 degrees left and a vertical speed of -10,912 ft/min.
It looks to me like the autotrim was the last nail in the coffin....
I'm surprised an A330 does not have an AoA indicator.

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Re: Air France jet missing

Postby flyboy2548m » Fri May 27, 2011 12:35 pm

I'm surprised an A330 does not have an AoA indicator.
You know of an airliner that does?
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Re: Air France jet missing

Postby Procede » Fri May 27, 2011 12:40 pm

I'm surprised an A330 does not have an AoA indicator.
You know of an airliner that does?
Not on an airliner, but then I have never looked for it. I have seen one in a Cessna Citation.

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Re: Air France jet missing

Postby flyboy2548m » Fri May 27, 2011 12:42 pm

I'm surprised an A330 does not have an AoA indicator.
You know of an airliner that does?
Not on an airliner, but then I have never looked for it. I have seen one in a Cessna Citation.
Good for you.
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Re: Air France jet missing

Postby J » Fri May 27, 2011 1:17 pm

"We have no valid indications"
Pilots battled with controls of Air France crash plane for four minutes

The Airbus A330 jet climbed to 38,000 feet and then began a three and a half minute descent, rolling from left to right, with the youngest of three pilots handing control to the second most senior pilot one minute before the crash.

The timeline was given in a note by France's BEA crash investigation authority, which said it was too early to give the causes of the crash ahead of a fuller report in the summer.

The pilots of Air France flight AF447 from Rio to Paris saw different and invalid speeds on their instruments before the Airbus A330-203 crashed into the Atlantic in June 2009, France's BEA aviation safety agency said Friday.

"We have no valid indications," one pilot was quoted as saying as the aircraft with 228 people aboard dropped towards the sea, more than three minutes before it hit the water.

The captain, who had left the cockpit to take a rest, returned but did not retake control of the plane.

"There was an inconsistency between the speeds displayed on the left side and the integrated standby instrument system (ISIS). This lasted for less than one minute," the BEA said in statement following its analysis of the recovered flight data recorders.

Source http://www.telegraph.co.uk/news/worldne ... nutes.html

Here is a link to the preliminary report in English. Excerpt:
New findings
At this stage of the investigation, as an addition to the BEA interim reports of 2 July and 17
December 2009, the following new facts have been established:
ˆˆ The composition of the crew was in accordance with the operator’s procedures.
ˆˆ At the time of the event, the weight and balance of the airplane were within the operational
limits.
ˆˆ At the time of the event, the two co-pilots were seated in the cockpit and the Captain was
resting. The latter returned to the cockpit about 1 min 30 after the disengagement of the
autopilot.
ˆˆ There was an inconsistency between the speeds displayed on the left side and the integrated
standby instrument system (ISIS). This lasted for less than one minute.
ˆˆ After the autopilot disengagement:
„„the airplane climbed to 38,000 ft,
„„the stall warning was triggered and the airplane stalled,
„„the inputs made by the PF were mainly nose-up,
„„the descent lasted 3 min 30, during which the airplane remained stalled. The angle of
attack increased and remained above 35 degrees,
„„the engines were operating and always responded to crew commands.
ˆˆ The last recorded values were a pitch attitude of 16.2 degrees nose-up, a roll angle of
5.3 degrees left and a vertical speed of -10,912 ft/min.
http://www.bea.aero/fr/enquetes/vol.af. ... 011.en.pdf

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Re: Air France jet missing

Postby Procede » Fri May 27, 2011 2:13 pm

Look five posts up, except I replaced the weird characters with smiley arrows.

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Re: Air France jet missing

Postby Giles » Fri May 27, 2011 3:21 pm

Thanks for the updates Procede and J.

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Re: Air France jet missing

Postby J » Fri May 27, 2011 3:36 pm

Look five posts up, except I replaced the weird characters with smiley arrows.
Thanks. Noticed that after it was too late to delete the quote.

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Re: Air France jet missing

Postby flyboy2548m » Fri May 27, 2011 3:37 pm

It would be good to know what the right side was showing. It would also be good to know if the left side and the ISIS attitude information were in agreement. I can fly without an ASI all day, if I have a good altimeter, good ADI and good engines. Now, if everything was showing different stuff and they didn't know what to believe, that would really suck.
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Re: Air France jet missing

Postby OldSowBreath » Fri May 27, 2011 4:33 pm

And yet this will still be labeled pilot error. Something is dreadfully wrong here.

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Re: Air France jet missing

Postby Gabriel » Fri May 27, 2011 11:19 pm

Moderators,

Please merge this thread with the "Gabriel wins" one.

Another accident that could have been prevented by lowering the nose.
(acknowledged, flying the unreliable speed memory items for pitch and thrust would have been better as it would have prevented the stall in the first place).

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Re: Air France jet missing

Postby Giles » Sat May 28, 2011 12:40 am

And yet this will still be labeled pilot error. Something is dreadfully wrong here.
If I am understanding all the information released so far;

they did apply aft stick in response to and during a stall.

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Re: Air France jet missing

Postby Ed » Sat May 28, 2011 12:50 am

Moderators,

Please merge this thread with the "Gabriel wins" one.

Another accident that could have been prevented by lowering the nose.
(acknowledged, flying the unreliable speed memory items for pitch and thrust would have been better as it would have prevented the stall in the first place).
I am not sure how this applies. Lowering the nose when you are into stall and your instruments indicate stall and you are sure it is a stall is one thing. The indications we are seeing right now is that there were different readouts and therefore they did not even know if the stall warning was valid. In so much as you don't want to stall these aircraft, I will make an assumption that it is equally bad to overspeed. Dropping the nose at the first sign of trouble is a good first practice for Tomahawks and Cessnas in VFR, but I am not sure about high performance jet aircraft at high altitude.

It looks like there were about 12 critical minutes that involved flying into thunderstorm activity, conflicting instrument readings and a sleeping captain (and subsequent confusion as he decided to wake up and enter the event, thereby using up critical minutes I suppose) that all contributed in their part.

The good news is that it appears as faulty equipment, maintenance and pilot error are all contributors, so the lawyers will make out like bandits on this one (the families, not so much).

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Re: Air France jet missing

Postby 3WE » Sat May 28, 2011 1:52 am

I'm surprised an A330 does not have an AoA indicator.
You know of an airliner that does?
Given that theres a few other gauges here and there, including some critical stuff like cabin temperature, are AOA indicators a big distraction and detrement to the safe operation of an airliner?
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Re: Air France jet missing

Postby 3WE » Sat May 28, 2011 1:56 am

Sorry for the paraphrasing- something happened when I hit submit
...they shold have lowered the nose to recover from the stall...
...they had bad data, and lacked clear indications of a stall...
Does a nose-up attitude combined, a brisk descent and uncontrolled rolling count as indications?
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Re: Air France jet missing

Postby flyboy2548m » Sat May 28, 2011 2:51 am

Given that theres a few other gauges here and there, including some critical stuff like cabin temperature, are AOA indicators a big distraction and detrement to the safe operation of an airliner?
Might as well install ballistic parachutes then. Don't worry, 3BS, you'll get that one next month sometime. Or not at all.
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Re: Air France jet missing

Postby flyboy2548m » Sat May 28, 2011 2:57 am

I am not sure how this applies.
To Gabriel everything within a nautical mile of the word stall applies. It's his pet issue, this whole stall-and-bury-the-nose business. It's a dead horse that he not only has killed, then beat for three days, then ate, but also shit it out and ate is as his own shit again.

Nothing like OCD with illusions of grandeur. You say stall and he'll go off for fifteen pages, plus he now has a new supporter in that dipshit Evan at the other site.
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Re: Air France jet missing

Postby 3WE » Sat May 28, 2011 12:08 pm

Stalls- where pilots continued to pull up- have caused a lot of crashes, Flyboy, it's that simple, and apparently there's a little bit of relevance to this crash.

And while we're on the subject, how do you like this article (near-total gloss over of the instrument and control systems).

PARIS (Reuters) – A French airliner plunged out of control for four minutes before crashing into the Atlantic in 2009, investigators said, in a report raising questions about how crew handled a "stall alarm" blaring out in the cabin.

Information gleaned from black boxes, and recovered almost two years after the disaster killed 228 people, confirmed that speed readings in the Airbus cockpit had gone haywire, believed to be linked to the icing of speed sensors outside the jet.

As Air France pilots fought for control, the doomed A330 dropped 38,000 feet, rolling left to right, its engines flat out but its wings unable to grab enough air to keep flying.

The plane crashed on June 1, 2009, en route from Rio de Janeiro to Paris. Black boxes stopped recording at 0214 GMT.

France's BEA crash investigation agency said in a detailed chronology of the crash that commands from the controls of the 32-year-old junior pilot on board had pulled the nose up as the aircraft became unstable and generated an audible stall warning.

Aviation industry sources told Reuters that this action went against the normal procedures which call for the nose to be lowered in response to an alert that the plane was about to lose lift or, in technical parlance, 'stall'.

This type of aerodynamic stall is nothing to do with a stall in the engines, both of which kept working as crew requested.

"A stall is the moment at which a plane stops flying and starts falling," said David Learmount, operations and safety editor at the British aviation publication Flight International.

A top aircraft industry safety consultant said the standard guidance in the Airbus pilot manual called in this event for the pilot to lower the nose by pushing the control stick forward.

"The BEA is now going to have to analyze and get to bottom of how crew handled this event," said Paul Hayes, safety director at Ascend Aviation, a UK-based aviation consultancy.

"The big question in my mind is why did the pilot flying (the aircraft) appear to continue to pull the nose up," he said.

French investigators said the emergency began with the autopilot disengaging itself two and a half hours into the flight and the junior pilot, who had been in control at take-off, picked up manually and saying "I have control."

The autopilot appears to have responded to a loss of reliable airspeed information. This was accompanied moments later by the disembodied voice of a recorded "stall" alert.

It is what happened next that is likely to fuel most theories on what preceded the crash, but Air France and its main pilots union insisted faulty speed probes were the root cause.

In a passage likely to attract particular scrutiny, the BEA said the pilot "maintained" the nose-up command despite fresh stall warnings 46 seconds into the four-minute emergency.

"The inputs made by the pilot flying were mainly nose-up," the report added.

The Airbus jet climbed 3,000 feet to 38,000 feet despite the crew having decided earlier against a climb, and then began a dramatic descent, with the youngest pilot handing control to the second most senior pilot a minute before impact.

The captain returned after "several attempts" to call him back to the cockpit but was not at the controls in the final moments, according to information gleaned from black boxes.

By the time the 58-year-old returned, just over a minute into the emergency, the aircraft was in serious trouble: plunging at 10,000 feet a minute with its nose pointing up 15 degrees and at too high an angle to the air to recapture lift.

The BEA did not provide extracts of the transcript for the last minute before the jet hit the water with its nose up.

It promised a fuller interim report which could say more about the causes of the crash in July.

SLIGHT TURBULENCE AHEAD

Relatives of victims had waited long for the report.

"It's very emotional to see the unrolling minute by minute or second by second at some points of what happened," said John Clemes, vice president of the families' support group.

"You automatically think of your family member and how they were living through this. It's the events that caused the deaths of 228 people so it's traumatic and moving."

The BEA report put to rest speculation that the pilots recklessly flew into the center of an equatorial storm cell.

Pilots had decided calmly to alter course slightly to avoid turbulence shortly before the crisis. But the pilot did tell flight attendants to prepare for a "little bit of turbulence."

"In two minutes we should enter an area where it'll move about more than at the moment; you should watch out," he told cabin staff. "I'll call you back as soon as we're out of it."

Air France said the crew had displayed a "totally professional attitude" and stayed committed to the end.

The crew's response to stall warnings contrasts with advice to pilots contained in an Airbus training seminar in October last year, according to a document obtained by Reuters.

In large red capital letters, the slide presentation says that in the event of a stall warning, pilots should "APPLY NOSE DOWN PITCH CONTROL TO REDUCE AOA (ANGLE OF ATTACK)."

Two aviation industry sources said the drill in force at the time of the accident was to apply full thrust and reduce the pitch attitude of the aircraft, which means lowering the nose.

Later guidance calls for pilots to push the nose down and adjust thrust as necessary, they said, asking not to be named.

Despite the apparent anomaly, aviation experts said it was early and most probably far-fetched to blame the miscommands -- so basic one compared it to hitting the accelerator instead of the brake when facing a car collision -- on a conscious error.

"One of the weird things about this is that the aircraft was definitely stalled, because the crew had had a stall warning, but they were not doing anything to recover from the stall," Learmount said. "It was almost as if they didn't know the aircraft was stalled, because they could have recovered."

The report and a more detailed follow-up are eagerly awaited by lawyers representing victims' families, but cannot be used in many courts. A separate French criminal probe is also under way.
Last edited by 3WE on Sat May 28, 2011 12:11 pm, edited 1 time in total.
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Re: Air France jet missing

Postby reubee » Sat May 28, 2011 12:10 pm

At around 2 h 11 min 40 , the Captain re-entered the cockpit. During the following seconds,
all of the recorded speeds became invalid and the stall warning stopped.
Note: When the measured speeds are below 60 kt, the measured angle of attack values are considered
invalid and are not taken into account by the systems. When they are below 30 kt, the speed values
themselves are considered invalid.
The altitude was then about 35,000 ft, the angle of attack exceeded 40 degrees and the vertical
speed was about -10,000 ft/min. The airplane’s pitch attitude did not exceed 15 degrees
and the engines’ N1’s were close to 100%. The airplane was subject to roll oscillations that
sometimes reached 40 degrees. The PF made an input on the sidestick to the left and nose-up
stops, which lasted about 30 seconds.
At 2 h 12 min 02, the PF said "I don’t have any more indications", and the PNF said "we have
no valid indications". At that moment, the thrust levers were in the IDLE detent and the
engines’ N1’s were at 55%. Around fifteen seconds later, the PF made pitch-down inputs. In
the following moments, the angle of attack decreased, the speeds became valid again and the
stall warning sounded again.
Am I interpreting this section correctly in that it is saying that even though the aircraft was in a stall situation, the stall warning stopped sounding because the speeds were so low? So the pilot finds himself in a situation where the warning sounds and he responds, the warning stops (even though the condition still exists) and again he responds, and then the warning sounds again. So not only giving an inaccurate situation of what is occuring but providing false feedback to the pilot in that he thinks his actions are producing a certain response when they aren't.

Also is there a similarity with Perpingnan with the elevator trim ending up on the limits and no action being taken to alter it?
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Re: Air France jet missing

Postby flyboy2548m » Sat May 28, 2011 12:43 pm

Stalls- where pilots continued to pull up- have caused a lot of crashes, Flyboy, it's that simple...
The only thing that's simple is that you're a moron, 3BS. It sounds to me that this crew was dealing with a situation where no two instruments agreed, with stall warnings that came and went, on top of some serious turbulence at night.

I will not pass judgment on this crew until I know what (if any) data that they were presented with was good. If the pitostatic system was compromised, perhaps they never saw the 10,000fpm+ descent rate, plus it appears they had three disagreeing ADIs and three disagreeing ASIs as well as three disagreeing altimeters. The comment "we have no valid data" points me in that direction.

So, they weren't just pulling the nose up, they were trying to make sense of data, none of which was making sense.
Last edited by flyboy2548m on Sat May 28, 2011 12:46 pm, edited 1 time in total.
"Lav sinks on 737 Max are too small"

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flyboy2548m
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Joined: Sat Feb 02, 2008 12:32 am
Location: Ormond Beach, FL

Re: Air France jet missing

Postby flyboy2548m » Sat May 28, 2011 12:45 pm

Am I interpreting this section correctly in that it is saying that even though the aircraft was in a stall situation, the stall warning stopped sounding because the speeds were so low?
That's exactly what happened, but don't tell 3BS/Gabriel. They'll just keep posting "he pulled up and crashed, he pulled up and crashed, nanernanernaner". Idiots.
"Lav sinks on 737 Max are too small"

-TeeVee, one of America's finest legal minds.


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