Posted on 06/04/2009 1:26:35 PM PDT by traumer
Air France pilots battled for up to 15 minutes to save the doomed flight that went missing over the Atlantic this week, electronic messages emitted by the aircraft have revealed.
Details have emerged of the moments leading up to the disappearance of flight AF 447 with 228 people on-board, with error messages reportedly suggesting the plane was flying too slowly and that two key computers malfunctioned.
Flight data messages provided by an Air France source show the precise chronology of events of flight AF 447 before it plummeted into the sea 400 miles off Brazil on Monday.
These indicate that the pilot reported hitting tropical turbulence at 3am (BST), shortly before reaching Senegalese airspace. It said the plane had passed through tall, dense cumulonimbus thunderclouds.
At this stage, according to a source close to the investigation cited by Le Monde, the Airbus A330-200's speed was "erroneous" - either too fast or too slow. Each plane has an optimal speed when passing through difficult weather conditions, which for unknown reasons, had not been reached by flight AF 447.
Airbus is expected to issue recommendations today to all operators of the A330 model to maintain appropriate thrust levels to steady the plane's flight path in storms.
At 3.10am, the messages show the pilot was presented with a series of major failures over a four-minute period before catastrophe struck, according to automatic data signals cited by the Sao Paulo newspaper, le Jornal da Tarde.
At this time, the automatic pilot was disconnected – either by the pilot or by the plane's inbuilt security system, which flips to manual after detecting a serious error.
(Excerpt) Read more at telegraph.co.uk ...
Bingo. It's difficult to fly with no windscreen, no Air Data probes and no engines.
We can all relate unpleasant experiences when flying. In the mid 70’s I was flying a Huey over some montains in Montana and had to add power to gain altitude I pulled the collective up along left pedal application when a compressor stall occured with loss of power. Thank God a snow field was in view for an auto-rotation landing. I am very religious but instead of praying, I remember thinking that I hope it doesn’t hurt. My prayers for those lost and their families.
We don’t “see” thunderstorms on our radar. As I mentioned before, we don’t have doppler radars. We only see precipitation on our radar. Of course, during the day, you can see the clouds where the heaviest precip is and deviate around them or go over them (if you’re above its cloud top). At night its a bit more challenging, but with the moonlight reflecting off the clouds and cloud-to-cloud lightning you usually get a good idea where and how high the thunderstorms are.
I beg to differ. They want to control through fear, and they will do it in every way and every chance they get. If they have to use a form of psych warfare, they will.
Understand our enemy is getting more and more sophisticated all the time, and sneakier. We underestimate them at our peril.
VHF would have a range of three or four hundred miles between planes at cruising altitude. My understanding was that pilots crossing oceans routinely exchange information about conditions encountered using air to air VHF. How many other airplanes would have been within that radius?
Sounds like that darn center fuel tank again.
I'm sure that there are lots of threats we never hear about, but just odd.
Now what if someone's figured out how to make planes go down and just doesn't need or want to make a splash. They're just going about the killing of infidels.
Praise Allah
They don't want glory but just the knowledge of destroying capitalist jet liners of the infidel will satisfy them.
I've got no dog in this fight,but defer to the pilots on this board.
The rudder stress to the tail during bad weather seems likely especially if the pilot really cranked on the controller of the tail rudder during high speed. That would have slowed down the plane, possibly torn the tail off and might have compromised the cabin... but over 10 minutes... maybe parts of the jet could transmit as it falls to the ocean???
Don't really know... but it's nice to see all the smart folk on the board.
The Pilots' View on Air France 447
Saunders also notes that if you’re caught in a storm at cruising altitude, where the air’s thin, the “buffer margin” on how much you can speed up and slow down narrows greatly. Current Airbus models are electronic wonders engineered to minimize the danger from human mistakes. They won’t fly faster than design specifications allow and they don’t let themselves stall. But an electronic problem could grow to a point where the computers could be disabled or given incorrect data. Without trying to condense Saunders’ technical explanation of stall speeds and engine thrust into a big inaccurate mess, suffice it to say that flying one’s way out of a severe storm at 35,000 feet is far trickier than one can imagine. A violent interaction of lightning, updrafting winds, and hail could produce a very ugly environment for an airplane.
Precisely my point. They are out to kill us and they don't care how or who even gets the "credit." Allah gets the credit.
That AE35 unit acting up again?
I’m curious about the apparent telemetry stream on this a/c.
You mentioned wind shear as a possible factor. Some people have heard of wind shear and don't really know what it is or why it is important. I put you in this class and called you on it.
ML/NJ
The Airbus radars may not be Doppler, but the precipitation shows up extremely well without Doppler processing, and very heavy precipitation is well-correlated with severe up- and down-drafts. The only problem is that in such cases, the 'thickness' of the region of high precipitation may be underestimated by the radar (including Doppler), due to the high attenuation of the microwave energy by the precipitation.
Iridium rents satellite phones for $35 per week, calls are $0.99/min. Doesn't sound all that expensive, even retail.
Sure, it does happen. Dallas weather is sketchy in the rain months. Never been diverted, but I know it happens. A lot of times we just go around the storm.
I grew up in Dallas. Live in Los Angeles area now, but do commute back often.
Does the 330 have ‘stick shaker’, or, joystick shaker, I guess? If so, does the autopilot automatically disengage when it activates?
There is a list of airline crashes caused by in-flight structural failure here. Looking through the list, it appears airframe failures are mainly due to metal fatigue and improper maintenance. Weather-related failures are quite rare. E.g., Braniff 250 in 1966 lost a wing in a severe squall. And BOAC 911, also 1966, seems to have fallen victim to violent winds over Mount Fuji. There is still controversy over whether AA 587 in 2001 lost its vertical stabilizer because of bad materials science or improper maneuvers by the pilot while coping with turbulence from a 747 wake.
Having been there I could easily see the pilots getting into undesirable Wx having just onboard radar on that leg.
It would be interesting to see, if there is one, the Wx record (satellite) for their flight path.
What was their enroute altitude?
There's some good stuff on FR, but also there sure is a lot of nonsense.
Uhhh genuis, a pilot on a neighboring flight saw a, quote, “brilliant white flash”.
What’s that sound like to you Einstein?
Still wanna rule out a bomb?
I’ve got extensive weather experience as it happens ... and as soon as I heard about the incident, I checked a satellite loop for that region. My first response was, wow that cloud mass blew up fast, even for the ITCZ zone.
Now I realize there was another thread on here with a good link to a meteorologist’s analysis.
But like myself (and he is probably more of an expert), he was not convinced it had to be weather-related, because while the event looked ominous on satellite, still there are thousands of flights every month that encounter similar or worse challenges and meet them without major incident.
So, one cannot close the book on other reasons, even though weather (and the updraft scenario leading the pack here) is obviously the most likely cause for whatever went wrong.
Other reasons might include pilot disorientation which would in itself be weather-related in some way, lightning causing a breakup or explosion (much against the statistical chances), or an explosion from a human cause.
There remains a slim possibility, I would think, that this will turn out to be a coincidence, that a terrorist or criminal act brought down the plane, just as it happened while they were flying through difficult weather.
The terrorist angle would be that France has yet to be a major target of terror, and the timing might seem right for this given the events involving France in the world. I admit this seems somewhat unlikely, but you never know, and if the explosion was time-controlled through the luggage by any chance, then you could speculate that it went off early perhaps. Or who knows, terrorists could have tried to storm the cockpit, and met with resistance. That could have led to events onboard bringing down the plane.
Also needing to be considered, this could have been a case of industrial sabotage. There was one company extensively represented onboard, giving their execs a reward trip. I would like to hear more about this company’s position in the commercial world, its rivals etc.
Still think turbulence or inadvertent entry into a thunderstorm cloud suddenly appearing would top the list of possible reasons, but there are other things not yet to be ruled out.
I’ll conclude with this ... the evidence points to an unusually strong ITCZ thunderstorm complex, but these are seldom as strong as storms encountered over the U.S. mainland in a cold front, so it’s not like they were flying into a major hurricane or tornadic thunderstorm complex. It was intense but I would have to think many pilots have seen worse.
Wind shear and turbulence are both experienced while in flight, and given the weather conditions of the location of the incident, could be a combination of both, either induced by the weather or pilot induced (or both). The twisting and turning of the jet while under extreme conditions, turbulence and wind shear most certainly was a factor.
We simply don't know for a certainty yet as to the actual "cause" of the mishap..
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