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Continental crash upstate New York

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http://answers.yahoo.com/question/index;_y...15115506AAHPQ6GPretty interesting response, and talks about some of the things you mentioned. I think this guy may be right. If the autopilot was disengaged with icing, it would be very hard to control with extreme trim. I also heard today that the NTSB found that the plane dropped straight down (complete stall) and lost more than 800 FT in 5 seconds. Sounds to me like flaps and gear caused the pitch of the plane to change, resulting in high angle of attack, because during approach, planes are very low speeds. The wings must have stalled and I'm guessing the tail did too with all this talk about icing on the horizontal stabilizer.Although I do not like to make bad speculations, maybe the pilots were not aggressive enough on preventing ice, or maybe the engaged it too late. I guess we will have to wait and see though to get the right answer though, because there are many different factors including the possibility of a failure of the anti-ice system.
The trouble with tail ice is it is hard to detect and by the time you know you have it it may be too late.Boots though they can be effective are not the same type of protection you get with a hot wing.My first flying teacher had a case of tail ice before it was much known. He came in for the ils-main wings looked ok-again a booted aircraft-dropped the gear and flaps and he said next thing he knew he was looking straight at the ground. Some how he got it under control just about when he touched the ground. He thought he was a gonner.Here is some good info:http://video.google.com/videoplay?docid=2238323060735779946

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Tail icing doesn't explain the initial 31* pitch up before the 45* pitch down.Tail icing would result in strictly a nose-down movement.


Ed Wilson

Mindstar Aviation
My Playland - I69

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Tail icing doesn't explain the initial 31* pitch up before the 45* pitch down.Tail icing would result in strictly a nose-down movement.
Seems like they are blaming the pilots for having the AP on in icing conditions. Listening to other aircraft that night, it seems some of them was also using the AP. One even told the tower he was going to do an autoland!

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Tom

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Tail icing doesn't explain the initial 31* pitch up before the 45* pitch down.Tail icing would result in strictly a nose-down movement.
The downward force of the horizontal stab would be degraded by the ice. Thus, the plane which I believe was reported on autopilot would trim more nose up . When the F/O selected landing flaps the autopilot could not retrim the plane quickly enough to keep the plane level, thus explaining the 31 degree pitch up?

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http://answers.yahoo.com/question/index;_y...15115506AAHPQ6GPretty interesting response, and talks about some of the things you mentioned. I think this guy may be right. If the autopilot was disengaged with icing, it would be very hard to control with extreme trim. I also heard today that the NTSB found that the plane dropped straight down (complete stall) and lost more than 800 FT in 5 seconds. Sounds to me like flaps and gear caused the pitch of the plane to change, resulting in high angle of attack, because during approach, planes are very low speeds. The wings must have stalled and I'm guessing the tail did too with all this talk about icing on the horizontal stabilizer.Although I do not like to make bad speculations, maybe the pilots were not aggressive enough on preventing ice, or maybe the engaged it too late. I guess we will have to wait and see though to get the right answer though, because there are many different factors including the possibility of a failure of the anti-ice system.
The de-icing system was turned on 11 minutes after departing Newark NJ. More info here:http://news.yahoo.com/s/ap/20090217/ap_on_...e_into_home_122Todd

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I don't believe so far NTSB has given any indication that a problem existed while flying in autopilot. NTSB has also cautioned about the reported 134 KIAS when gear/flaps deployed, suggesting that the speed needs to be confirmed. Some sites have been concerned that if 134 kts is correct, that seems slow for approach in icing conditions. scott s..

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I don't believe so far NTSB has given any indication that a problem existed while flying in autopilot. NTSB has also cautioned about the reported 134 KIAS when gear/flaps deployed, suggesting that the speed needs to be confirmed. Some sites have been concerned that if 134 kts is correct, that seems slow for approach in icing conditions. scott s..
Sounds like AP was disengaged only slightly before the moment of upset. Flaps 10 and gear down were selected somewhere around 26 seconds before end of CVR/FDR? Don't know which is being referenced. Full power is selected just 6 seconds after flaps 10 and gear down. Nose up 31 degrees max and nose down 45 degrees, rolled 46 degrees left and 105 degrees right. Pitch was 30 degrees nose down, rolled 26 degrees right with 100 KIAS on impact.Severe icing was not reported and most other aircraft on app were using AP. It's possible the crew fell behind the curve IN icing, as opposed to icing being the direct cause, or perhaps something malfunctioned.

- Chris

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Sounds like AP was disengaged only slightly before the moment of upset. Flaps 10 and gear down were selected somewhere around 26 seconds before end of CVR/FDR? Don't know which is being referenced. Full power is selected just 6 seconds after flaps 10 and gear down. Nose up 31 degrees max and nose down 45 degrees, rolled 46 degrees left and 105 degrees right. Pitch was 30 degrees nose down, rolled 26 degrees right with 100 KIAS on impact.Severe icing was not reported and most other aircraft on app were using AP. It's possible the crew fell behind the curve IN icing, as opposed to icing being the direct cause, or perhaps something malfunctioned.
Actually, the crew reported icing on their windscreen in the cockpit audio. That's pretty severe icing since they are typically heated and the FDR states anti-icing was on.

Ed Wilson

Mindstar Aviation
My Playland - I69

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Sounds like AP was disengaged only slightly before the moment of upset. Flaps 10 and gear down were selected somewhere around 26 seconds before end of CVR/FDR? Don't know which is being referenced. Full power is selected just 6 seconds after flaps 10 and gear down. Nose up 31 degrees max and nose down 45 degrees, rolled 46 degrees left and 105 degrees right. Pitch was 30 degrees nose down, rolled 26 degrees right with 100 KIAS on impact.Severe icing was not reported and most other aircraft on app were using AP. It's possible the crew fell behind the curve IN icing, as opposed to icing being the direct cause, or perhaps something malfunctioned.
In the midwest icing is pretty much in every winter forecast. Many times there is absolutely none, and other times it can be quite bad.If anything accurate can be said about the nature of the environment which produces icing conditions it is that it is fickle. Just as the surface has its own micro-climatology, so do clouds.That area just on the other side of the Great Lakes is well known for unpredictable icing, super cooled water droplets, and all kinds of other nasty stuff, and it can be quite localized.

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Actually, the crew reported icing on their windscreen in the cockpit audio. That's pretty severe icing since they are typically heated and the FDR states anti-icing was on.
I remember hearing somewhere that there was a crash sometime ago in a turboprop (I forgot which model) but some anti-ice devices do not go across the whole chord of surfaces, so even if the leading edge has ant-ice, other control surfaces may have ice on them. Not sure about the anti-ice on the Q400 though so it may be false.
In the midwest icing is pretty much in every winter forecast. Many times there is absolutely none, and other times it can be quite bad.If anything accurate can be said about the nature of the environment which produces icing conditions it is that it is fickle. Just as the surface has its own micro-climatology, so do clouds.That area just on the other side of the Great Lakes is well known for unpredictable icing, super cooled water droplets, and all kinds of other nasty stuff, and it can be quite localized.
Yup, the east coast generally has a lot of freezing rain because the temperatures usually hover around 30-34 degrees F when there is precip, so this could cause clear ice to form due to visible moisture freezing VERY rapidly. Right now we are getting some snow here in the DC area. Hoping school is closed early!Barometric pressure here is 29.90in and dropping, that means skies with moisture and lots of trouble for departing aircraft at KIAD and KHEF (temp is 32 degrees :()

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WSJ article today is pushing towards the idea of pilot flying mishandling a stick-shaker/ stick-pusher stall event. Seems a bit premature to me though. Doesn't delve into what caused the stall to begin with.scott s..

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WSJ article today is pushing towards the idea of pilot flying mishandling a stick-shaker/ stick-pusher stall event. Seems a bit premature to me though. Doesn't delve into what caused the stall to begin with.scott s..
We all know the WSJ is the bastion of truth when it comes to aviation news. :(

Ed Wilson

Mindstar Aviation
My Playland - I69

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Here is an interesting letter sent out to a pilot group at an airline:XX Pilots,There is a potentially significant hazard concerning the ILS to runway 23 in BUF.Information has been received indicating it is possible to obtain a significant nose pitch up, in some cases as much as 30 degrees, if the glide slope is allowed to capture before established on centerline. Pilots who are preparing to configure and land have the potential to experience abrupt pitch up, slow airspeed, and approach to stall if conditions present themselves in a certain manner.This effect is the result of an earthen obstruction close enough to the ILS to affect the integrity of the glide slope signal. This has resulted in the issuance of an advisory given on ATIS which states that "the ILS Glide Slope for runway 23 is unusable beyond 5 degrees right of course."When attempting to intercept the runway 23 ILS from right traffic, the ILS glide slope indication may read full deflection down. Just prior to intercept it may then move up in such as manner as to enable approach mode to capture in such a way as to result in a nose up pitch and loss of airspeed.XX Airlines has issued a notice reading: "Until further notice, when executing the KBUF ILS/LOC Runway 23, DO NOT select Approach Mode until established on the localizer inbound."This issue is being addressed on several levels in an attempt to address procedures, facilities, and communication regarding this matter. If you experience any issues related to this, please file an ASAP form and or call....

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