American 587 question

[Jack1985]

12 November 2001 when AAL587 came down we were told it was due to an over-reaction to wake-turbulence by the FO, at the time American Airlines trained its pilots to react to a sudden 90 degree bank angle induced by wake turbulence something the NTSB said was highly unrealistic and unlikely to out do 40 degrees - The FO in trying to maintain level wings in the wake he was encountering caused by the JAL 747 ahead smacked the rudder right and immediately left fearing the aircraft would suddenly bank to 90 degrees something he had trained for, he repeated the rudder commands until the stress load in the rudder reached a point where all three bearings failed simultaneously and the rudder detached leading to the deadly crash.

14 January 2014 - An Alaska 737-400 encountered two sudden 70 degree bank angles (both different directions) landing in Vancouver caused by an Air Canada A330, but continued for a safe landing.

My question - Have the NTSB stopped American training their pilots for something that could now definitely happen? They stopped training them to deal with 90 degree sudden bank angles caused by wake following the release of the final report for American 587.

I understand that the stress load put on the rudder caused it to out do its design limits, however when confronted with two massive 70 degree bank angles like the Alaska flight above you have no option but to command rudder in the opposite direction. And say you were confronted with 4 sudden different bank angles then the stress load will inevitably build to match that on AAL587, Some may say my above point is unrealistic however the Alaska flight proved that the 40 degree theory to be totally incorrect.

[FIRESYSOK]

Go ahead and mash the rudder in such a '70 degree death spiral' and we'll be reading about you on the Daily Mail.

Where did you read the 737 crew had tapped all aileron authority and had to resort to rudder to correct, or is it your theory?

[Jack1985]

I see you already have a position in the daily mail, I merely asked a question and never once said they did any such maneuver.

However my colleague is trained to do it, my point still stands.

[MrSnuggles]

A a materials engineer I think you have to factor in several "highly unlikely" scenarios when designing aircraft parts. The rudder is consequently designed to take huge loads, much higher that you'd expect in normal flight and upset.

That said, I would like to know more about the incident you refer to. What actions did the crew take, for instance. How did they handle the rudder, for example. Do you have a link to the accident/incident report?

The important thing about the rudder is to handle it carefully while in the air, because the loads there will be much higher since you have much more speed. This goes for all rudders of all materials - composites as well as aluminium. Remember, in the 587 accident the rudder managed to snap off the tail fin bolted to the fuselage with conventional metal materials, just as in any airplane. It wasn't so much a composite failure as it was a metal material overload on the tail fin bolts.

Adjusting the rudder for wake turbulence may very well be done if it is made with caution and combined with other evasive control surface maneuvres. The solution for big jets would not necessarily be to repeatedly slam the rudder to its maximum position left-right-left-right. This would work for WWII piston fighters because of their other handling characteristics (among them: much lower speeds) but passenger jets is a whole'nother piece of cake.

[KBPsen]

and never once said they did any such maneuver.But you did.

when confronted with two massive 70 degree bank angles like the Alaska flight above you have no option but to command rudder in the opposite direction.

[Jack1985]

What actions did the crew take, for instance.

That I do not know, I'm not sure if there's going to be an investigation there's a small bit of information here - Incident: Alaska B734 at Vancouver on Jan 14th 2014, wake turbulence rolls aircraft to 70 degrees (http://avherald.com/h?article=46e90ec2&opt=0)

The solution for big jets would not necessarily be to repeatedly slam the rudder to its maximum position left-right-left-right.

Precisely, gentle rudder movements in the opposite direction combined with aileron is what I've been thought - It strikes me though how know one in American seemed to point this out to the FO on #587 that slamming in the opposite direction would lead to high stress loads which was concerning, I remember a Captain he had flown with was concerned so much when the same FO done it before the accident flight he took control and reported it, nothing was done and he was tested in the same circumstance, again.

But you did.

Please re-quote my post and point out where I indited that crew please? You'll notice I gave my own opinion, christ bugger off.

[Clandestino]

An Alaska 737-400 encountered two sudden 70 degree bank angles (both different directions)

An Alaska Airlines Boeing 737-400, registration N756AS performing flight AS-703 from Los Angeles,CA (USA) to Vancouver,BC (Canada), was on final approach to Vancouver's runway 08L at 1900 feet about 6.5nm behind an Air Canada Airbus A330-300, registration C-GFAJ performing flight AC-855 from London Heathrow,EN (UK) to Vancouver,BC (Canada), when the aircraft rolled left to 70 degrees of bank twice.

The FO in trying to maintain level wings in the wake he was encountering caused by the JAL 747 ahead smacked the rudder right and immediately left fearing the aircraft would suddenly bank to 90 degrees something he had trained for, he repeated the rudder commands until the stress load in the rudder reached a point where all three bearings failed simultaneously and the rudder detached leading to the deadly crash.

in the 587 accident the rudder managed to snap off the tail fin bolted to the fuselage with conventional metal materials

I'm not sure if there's going to be an investigation there's a small bit of information here

The Canadian TSB reported...

You'll notice I gave my own opinion, christ bugger off.How polite of you.

[MrSnuggles]

I am of course not at all informed of any training made by American Airlines, not now nor before. I can only give general information about aircraft materials and parts.

As for your link to the incident I read:

the aircraft rolled left to 70 degrees of bank twice

which seems a bit odd. This being a 737-400 I start wonder if they have the same rudder system as the infamous USAir 427 et al. (I know this is a veeery long shot! LOL) Sure, the A330-300 is bigger than the B737-400 but not THAT much bigger. If they maintained separation it is strange that they should have had such a severe reaction, unless other factors were involved. I will leave this strange behaviour to be explained by a seasoned pilot.

[Jack1985]

Clandestino

My question from the start of this thread has been to ask pilots there own views about one of the NTSB's determinations that American used irenaeus training techniques in relation to wake turbulence. My question was why did the NTSB make such a determination to American which actually stopped the training for a sudden 90 degree bank. Although such a bank of 90 degrees has never been reported from wake turbulence, the investigator at the time said he had never heard of more than 40 degree wake bank angle, the Alaska two days ago encountered two sudden 70 degree banks.


I never mentioned any maneuvers of any kind by the Alaska crew.

I pointed out the maneuvers performed by the FO on 587.


You, KBPsen and FIRESYSOK would rather play the big boy role behind a computer screen and detract from a valid argument in which I would like to hear comments from people who actually fly.

Thank you.

[Jack1985]

which seems a bit odd. This being a 737-400 I start wonder if they have the same rudder system as the infamous USAir 427 et al. (I know this is a veeery long shot! LOL) Sure, the A330-300 is bigger than the B737-400 but not THAT much bigger. If they maintained separation it is strange that they should have had such a severe reaction, unless other factors were involved. I will leave this strange behaviour to be explained by a seasoned pilot.

That was my first concern however if this was wake turbulence it is probably one of the worst reactions by the aircraft to it I've known.

In relation to the historic 737 classics rudder problem the pilots in both cases the PF I believe (definitely on USAir 427) was trying to deflect the rudder in the opposite direction to get out of the roll actually horribly only to end up assisting in the crash, because the motor for the rudder had reversed in its operation i.e. the rudder pedals had switched, left was now right and so on, such a horrible outcome when both crews on the USAir and United flights had fought to the very end with the aircraft both those accidents.

[ATC Watcher]

I would like to hear comments from people who actually fly.

Nice way to start WW III on PPRuNe :E

[Jack1985]

Nice way to start WW III on PPRuNe

Not my aim at all haha, but would really like experienced answers rather than headaches. :)

[Clandestino]

My question was why did the NTSB make such a determination to American which actually stopped the training for a sudden 90 degree bank.Question is nonsensical because no such thing ever occurred.

[Jack1985]

Question is nonsensical because no such thing ever occurred.

Wow, talk about walking into your own trap mate!

''The NTSB indicated that American Airlines' Advanced Aircraft Maneuvering Program tended to exaggerate the effects of wake turbulence on large aircraft. Therefore, pilots were being trained to react more aggressively than was necessary.''

Link - Press Release [October 26, 2004] - NTSB - National Transportation Safety Board (http://www.ntsb.gov/news/2004/041026.htm).

http://www.youtube.com/watch?v=lNWbUB68oO4 (90 degree training segment in the AAMP.)

[KBPsen]

detract from a valid argumentWhat argument?

As for your opening post, you are mixing fact (what few reported and you got some of it wrong) with fiction (your assumptions) and then you expect people to relate to the result in a serious way or answer a question that has little basis in reality.

And you have posted in the wrong forum, btw.

[Jack1985]

KBPsen

Please point out what is fiction,

Thanks

[MrSnuggles]

Would you please stop bitching about details?

As I understood it, the OP wants to know if there is any training regarding <70 degrees of bank angle due to (what may be) wake turbulence.

The Alaska flight is used by the OP as an example of a real life situation where the bank angle exceeds the estimated maximum of 40 degrees suggested by the NTSB after the 587 incident.

OP then, albeit somewhat vague, poses the question if it is possible to get out of the 70 degree bank angle without heavy rudder use.

[Clandestino]

NTSB stepped down on AA Advanced maneuvering program which overemphasized the use of rudder in recovery from extreme bank and understated the dangers of using it. As such it turned out to be lethal when misunderstood and misapplied. Training for 90 degrees (and more) bank recovery was never stopped! It is still happily ongoing everywhere, we are just careful to teach people there is no point in using rudder when roll authority is sufficient.

In relation to the historic 737 classics rudder problem the pilots in both cases the PF I believe (definitely on USAir 427) was trying to deflect the rudder in the opposite direction to get out of the roll actually horribly only to end up assisting in the crash, because the motor for the rudder had reversed in its operation i.e. the rudder pedals had switched, left was now right and so on, such a horrible outcome when both crews on the USAir and United flights had fought to the very end with the aircraft both those accidents.This is fiction.

[Jack1985]

Would you please stop bitching about details?

As I understood it, the OP wants to know if there is any training regarding <70 degrees of bank angle due to (what may be) wake turbulence.

The Alaska flight is used by the OP as an example of a real life situation where the bank angle exceeds the estimated maximum of 40 degrees suggested by the NTSB after the 587 incident.

OP then, albeit somewhat vague, poses the question if it is possible to get out of the 70 degree bank angle without heavy rudder use.

Thanks MrSnuggles, that's precisely my argument, they have nothing valid to add but petty remarks.

This is fiction.

''The safety issues in this report focused on Boeing 737 rudder malfunctions, including rudder reversals; the adequacy of the 737 rudder system design; unusual attitude training for air carrier pilots; and flight data recorder (FDR) parameters.''

Link - Accident Investigations - NTSB - National Transportation Safety Board (http://www.ntsb.gov/investigations/summary/AAR9901.html)

Again on the program air crash investigation, this is shown in the episode ''Hidden Danger'' which dramatizes the crash of UsAir 427, United Airlines Flight 585 and Eastwind Airlines Flight 517.

Hmm yes fiction, from your mouth since all you want to do is detract from my argument you continue to lose, now please leave if you have nothing to contribute.

[aterpster]

Jack1985:

What was the speed and configuration of the Alaska 737-400? I presume it was likely well below the 250 KIAS the ill-fated American flight was doing.

If the wing went down 70 degrees at approach speed a coordinated recovery with aileron and rudder would be most appropriate. If shortly thereafter the other wing went down to 70 degrees, the same control inputs in the appropriate direction would also be valid. That would be far different than rapid opposite direction large inputs of the rudder only at 25o KIAS.

What I am suggesting in the Alaska case is some rudder, not full rudder.

[Airbubba]

I had the 'Advanced Aircraft Maneuvering Program' presented during sim training in the late '90's.

I was skeptical of these rudder excursions and not surprised when the AA 587 NTSB report came out:

Interesting note about AA Airbus crash in NYC


The National Transportation Safety Board determines that the probable cause of
this accident was the in-flight separation of the vertical stabilizer as a result of the loads beyond ultimate design that were created by the first officer’s unnecessary and excessive rudder pedal inputs. Contributing to these rudder pedal inputs were characteristics of the Airbus A300-600 rudder system design and elements of the American Airlines Advanced Aircraft Maneuvering Program."

I'm not sure if this has been covered before but a safety award was given for developing that program five days before the accident.

http://www.flightsafety.org/citation...burgh_cit.html

Airbubba: Yep, this program filtered down to the other airlines. I was given a version of the training that included the hard rudder kicks to get the nose back down to the horizon in some attitudes. I questioned whether you really wanted to do this in a transport aircraft but was told that it was all within the design envelope. I guess it turns out that it wasn't...

http://www.pprune.org/tech-log/257236-interesting-note-about-aa-airbus-crash-nyc.html#post3033522

AA Captain Warren Vanderburgh is credited with developing the Advanced Aircraft Maneuvering Program in response to some airliner accidents involving upsets. In theory at least, some of these upsets may have been recoverable through timely aggressive control inputs. However, like moving the flap handle when you get a GPWS, unless you do it just right, you may make the situation worse, not better, in my opinion.

Captain Vanderburgh is more widely known for his 'Children of the Magenta Line' lectures warning of the dangers of reliance on ever increasing flight deck automation.

[Avionista]

MrSnuggles:

Remember, in the 587 accident the rudder managed to snap off the tail fin bolted to the fuselage with conventional metal materials, just as in any airplane. It wasn't so much a composite failure as it was a metal material overload on the tail fin bolts.

I don't think this is quite accurate. I happened to watch the "DISCOVERY" documentary about the 587 crash yesterday and an NTSB investigator showed that the laminated composite 'eye-holes' on the tailfin mountings failed when they were subjected to a side load of about 250,000 lbs. (The maximum design load was stated to be 100,000 lbs). The NTSB actually tested to destruction a sample tailfin supplied by Airbus. There was no mention in the programme of the steel bolts which go through the tailfin mountings having failed.

[Jack1985]

What was the speed and configuration of the Alaska 737-400? I presume it was likely well below the 250 KIAS the ill-fated American flight was doing.


Have no idea I'm afraid. The stress loads from use of rudder at higher speeds are greater I know that, but I have no idea I'm hoping you do of the kind of stress loads created at lower speeds, obviously as you pointed out the Alaska flight was on approach so presumably slower the 200kts.

What I am suggesting in the Alaska case is some rudder, not full rudder.

Yes exactly, easy on the rudder, and full aileron both in the opposite direction its simple to understand in theory, however I'm sure we would all react differently being presented by two 70 degree banks unexpectedly. My concern is that the NTSB in believing anything over 40 bank was unrealistic, this was 70 and so I fail to see why the AAMP program needed to be amended to exclude the 90 degree bank situation. Obviously hogging the rudder left and right was totally wrong, but being thrown like that two 70 degree banks on the Alaska it concerns me possibly say if it had occurred when he was faster and say he had smacked the rudder we could have had the same event.

Now thats my opinion and assumption I have no idea how the Alaska crew responded.

[Jack1985]

I don't think this is quite accurate. I happened to watch the "DISCOVERY" documentary about the 587 crash yesterday and an NTSB investigator showed that the laminated composite 'eye-holes' on the tailfin mountings failed when they were subjected to a side load of about 250,000 lbs. (The maximum design load was stated to be 100,000 lbs). The NTSB actually tested to destruction a sample tailfin supplied by Airbus. There was no mention in the programme of the steel bolts which go through the tailfin mountings having failed.

Yes I believe it was the composite materials failed, which caused that concern back in 2001 that it wasn't as tough.

[Clandestino]

These are facts:

The National Transportation Safety Board determines that the probable cause of the USAir flight 427 accident was a loss of control of the airplane resulting from the movement of the rudder surface to its blowdown limit. The rudder surface most likely deflected in a direction opposite to that commanded by the pilots as a result of a jam of the main rudder power control unit servo valve secondary slide to the servo valve housing offset from its neutral position and overtravel of the primary slide.

This is misunderstanding of the facts:

the motor for the rudder had reversed in its operation i.e. the rudder pedals had switched, left was now right and so onThe actuator did not reverse, it went into extreme position and jammed there.

AA587 case tends to get resurrected around here every couple of months by someone whose strength of opinion is inversely proportional to aeronautical knowledge and understanding. As for Alaska incident, TSBC will tell.

[Jack1985]

You are completely misunderstanding the facts you so like to confuse.

The rudder surface most likely deflected in a direction opposite to that commanded by the pilots

UsAir 427 rolled right, the captain applied full left rudder - the rudder had reversed so that actually applying left rudder was now right - The NTSB investigator states this on the program ''Hidden Danger'' on ACI - I only brought up this thread because I watched that documentary last Thursday, American 587 Saturday and noticed the Alaska incident today.

May I ask do you actual fly? Because I've met you're type to frequently, the type who likes to believe there in the industry.

[Jack1985]

Clandestino

Mayday, Air Crash Investigation - S04E05 - Hidden Danger (Mystery Crashes) Part 5 - YouTube - Please watch from 4:00 on, you might then for once understand facts.

Now can we please get back to the thread.

[Clandestino]

Darn, I stand corrected. Now this opens whole new can of worms regarding the use of rudder in roll recovery, doesn't it?

[One Outsider]

Now can we please get back to the thread.Perhaps you mean get back to the subject, which I'm curious what exactly is, as it seems to be all over the place.

[Jack1985]

Perhaps you mean get back to the subject, which I'm curious what exactly is, as it seems to be all over the place.

It's this - Since AAL587 the over-use of rudder has been widely etched in everyone's mind and the reason the FO used such hard rudder was because of the 90 degree AAMP simulation, the NTSB believe anything over 40 degrees was imaginary - highly unlikely, one investigator stated 10 degrees or more was extremely rare. We have an Alaska that encountered two 70 degree rolls, its very difficult to get out of that without a lot of rudder as well as aileron.

I'm concerned that too much emphasis was put on the stamping of the rudder, we all know thats wrong. Not enough emphasis was put on the fact that 90 degrees roll is very much plausible, and you're not going to get out of that without rudder - if you're at 250kts passing through 2,300 (or any high speed/altitude) as was the case for AAL587 and confronted with that you mean to tell me we aren't going to see another accident.

I'm very much concerned.

[4Greens]

In a swept wing aircraft the rudder is used for engine failures and cross wind landings.

[Jack1985]

In a swept wing aircraft the rudder is used for engine failures and cross wind landings.

True and in many other ways also. Try not using your rudder in a roll and let me know how you get on.

[One Outsider]

You seem to be basing a lot of your conclusions and drawing most of your "facts" - if not all of them - from TV-shows made for entertainment purposes.

[Jack1985]

Not at all I've sourced all my information before posting just check back on other posts, and I'm hoping you're not saying ACI is falsifying NTSB and numerous other world crash reports with the aid of the original investigators??

[flyboyike]

I'm very much concerned.


I wouldn't sweat it, based on you being from Ireland, I'd say the odds of you ending up on an AS 734 are pretty well nil.

Oh, and I've been flying swept-wing aircraft for just over seven years now, and haven't used the rudder outside of crosswinds and OEI practice so much as once yet. I'm still alive.

[flyboyike]

Not at all I've sourced all my information before posting just check back on other posts, and I'm hoping you're not saying ACI is falsifying NTSB and numerous other world crash reports with the aid of the original investigators??



ACI is first and foremost an entertainment product, not a terrible one, but one nonetheless.

[Jack1985]

I wouldn't sweat it, based on you being from Ireland, I'd say the odds of you ending up on an AS 734 are pretty well nil.

Oh, and I've been flying swept-wing aircraft for just over seven years now, and haven't used the rudder outside of crosswinds and OEI practice so much as once yet. I'm still alive.

Ha you never know, us Irish have plenty of US relatives!

I'm not questioning that, and in the cases you've given you don't need to, but are you telling me you're not going to use rudder when thrown by two 70 degree rolls?

ACI is first and foremost an entertainment product, not a terrible one, but one nonetheless.

True but the start of the program goes like ''based on a True Story using ATC transcripts, crash investigators etc'' carries a certain stack of responsibility, and wouldn't it be pprune first where its credibility is doubted. :}

[One Outsider]

I'm very much concerned.It's all a bit too contrived for my taste.

[flyboyike]

I'm not questioning that, and in the cases you've given you don't need to, but are you telling me you're not going to use rudder when thrown by two 70 degree rolls?


That's exactly what I'm telling you. Between the ailerons and spoilers I've got plenty of roll authority. Now, if the aircraft is not responding to aileron inputs, that's a whole separate conversation.

Sorry if that's not what you want to hear, I have a knack for disappointing people.

[Jack1985]

It's all a bit too contrived for my taste.

Suppose I better shave my head and roll around on a wrecking ball and share my point of view hey!

That's exactly what I'm telling you. Between the ailerons and spoilers I've got plenty of roll authority. Now, if the aircraft is not responding to aileron inputs, that's a whole separate conversation.

Sorry if that's not what you want to hear, I have a knack for disappointing people.

I appreciate your response thats all I've asked to hear on this forum so you ain't disappointing no one.

It's weird I've been taught (granted a C172 - going for my PPL) positive (i.e. gentle) rudder and aileron opposite direction then stabilise - the airline I'm a ground handler for from speaking to pilots about it do the same. Is it airline specific or even down to what the person would rather do which are both totally respectable decisions once its all done right!

[Aluminium shuffler]

Jack, you DO NOT use rudder for upset recoveries unless you have run out of aileron authority, have an aileron jam or need to yaw the nose down in a high nose, low speed recovery where you have already rolled the aircraft over past 60 deg AOB deliberately.

I did the Boeing Advanced Maneouver Programme some time around 2000 that was designed to teach recovery from rudder hard-overs. We ended the training with flap-40 approaches with full rudder deflection kicking in at 1500', and would recover with the rudder still jammed from a 135 deg AOB to climbing away with less than 1000' loss, and that was done for training purposes with the PF having to lower their head to be "momentarily disorientated" as to which way the aircraft had departed.

Any time you are going to use the rudder in flight, you do so gingerly and reluctantly, and only as a last resort. Your comments about stomping on the pedals or using full rudder as a procedure show a complete lack of understanding of swept wing flight, and your numerous references to TV programmes, which are often misleading and inaccurate, including ACI, suggests you are not a commercial pilot. To that end, I think you owe some of the other respondents on this thread an apology for being argumentative and dismissing their posts.

[Jack1985]

Any time you are going to use the rudder in flight, you do so gingerly and reluctantly, and only as a last resort. Your comments about stomping on the pedals or using full rudder as a procedure show a complete lack of understanding of swept wing flight, and your numerous references to TV programmes, which are often misleading and inaccurate, including ACI, suggests you are not a commercial pilot. To that end, I think you owe some of the other respondents on this thread an apology for being argumentative and dismissing their posts.

Sir I never once mentioned in flight, you think I'm suicidal? I was talking in the aspects approach/departure in relation to a sudden bank from wake. My comments about stomping on the rudder were to show what the outcome was I hope you don't believe I'm recommending that to anyone, I repeated how dangerous that was and its result on 587 numerous times. The rudder reversal was correct - I referenced the NTSB report and a clip from ACI.

I am not a commercial pilot where did I say I was?

Hmm apology for what, being truthful and asking a question with all facts provided?

Thanks for input.

[stator vane]

With over 8600 hours in B738, +1700 in B732, +2800 in B733 and +2700 in B734, one might say i "are" a pilot.

After reading the report and noticing it was a 734, the first question to arise in my head was, "was it really 70 degrees bank?" There was no info as to whether this was verified from the flight data recorder or a QAR or simply a statement from the pilots. In the book about the USAir flight, it was shown that a report from another pilot about a bank event at altitude on another 732, was not that much of a bank, yet still a significant amount. Pg 208, Flight 427, Gerry Byrne, 2002.
(Pilot said aircraft rolled 30 degrees right. FLT data recorder showed only 10 degrees) "pilots...have a tendency to either exaggerate or underestimate the effect of an in-flight emergency." So, i honestly must wait for more information.

Then you ask if we could avoid using the rudder in a 70 degree bank: i have only had it in sim training where they are telling us to use the rudder, so i did then. But both hands up, if it happens when next in the 738, i will use aileron and unload the elevator before using the rudder. Rudder will be a last resort. And even when using the rudder, I would never "kick" it back and forth, which did the vertical stabilizer in on the AA flight.

We must remember though that in most sim sessions, we are usually pre-warned about what will happen or at least which systems will be addressed. (At least here in the UK, which i honestly think is ridiculous) and our reactions are suspect as to whether they are truly honest.

[Jack1985]

With over 8600 hours in B738, +1700 in B732, +2800 in B733 and +2700 in B734, one might say i "are" a pilot.

After reading the report and noticing it was a 734, the first question to arise in my head was, "was it really 70 degrees bank?" There was no info as to whether this was verified from the flight data recorder or a QAR or simply a statement from the pilots. In the book about the USAir flight, it was shown that a report from another pilot about a bank event at altitude on another 732, was not that much of a bank, yet still a significant amount. Pg 208, Flight 427, Gerry Byrne, 2002.
(Pilot said aircraft rolled 30 degrees right. FLT data recorder showed only 10 degrees) "pilots...have a tendency to either exaggerate or underestimate the effect of an in-flight emergency." So, i honestly must wait for more information.

Then you ask if we could avoid using the rudder in a 70 degree bank: i have only had it in sim training where they are telling us to use the rudder, so i did then. But both hands up, if it happens when next in the 738, i will use aileron and unload the elevator before using the rudder. Rudder will be a last resort. And even when using the rudder, I would never "kick" it back and forth, which did the vertical stabilizer in on the AA flight.

We must remember though that in most sim sessions, we are usually pre-warned about what will happen or at least which systems will be addressed. (At least here in the UK, which i honestly think is ridiculous) and our reactions are suspect as to whether they are truly honest.

Oh exactly, I'm hoping we will hear more about the Alaska flight because two rounds of 70 degree bank is quite a lot to handle unexpectedly! Precisely, but what worries me is if I'm at 1,000ft when the day comes I'll hopefully be looking after folks in the back, then I think you have no option but to pull everything out of the bag if you've been thrown to a 70 degree bank by wake you're going to lose altitude some way or another and its basically how quick you react to get back stable, my gut instinct would be gentle rudder and full aileron in the opposite direction and relax the elevator, fully echo the comments you make about 587.

I really don't get why they do the pre-warnings, isn't the true performance from someone going to come out when they get the unexpected that is the ultimate test, its what most sim sessions are for the unexpected.

The 70 degrees I keep banging on about was a one event and yet to be confirmed, but its those one off events aviation has come to scrutinise so they don't happen.

I hope everyone understands I'm simply seeking pilots thoughts on what I've said, it's very beneficial for everyone especially when talking about the unexpected.

[MrSnuggles]

Hmm, as I recall it was the bolts that failed on AA587 but I might very well remember wrong. It was a while ago I read the report, please excuse my mistake.

It was long since I saw a more confusing thread, blabbering over (overly misunderstood) details, than this so I really appreciate stator vane for the nice and informational response. Thank you!

[Jack1985]

stator vane for the nice and informational response. Thank you!

Yes thanks from me too, and flyboyike. :)

[Aluminium shuffler]

To get rudder reversal you need to have an extremely high AOA. It was a phenomenon that the F4 Phantom could suffer on heavy take-offs. It is only likely to happen to an airliner in a deep stall, and is only happening because the wings are so heavily stalled that the yaw from the rudder and the subsequent change in airflow over each wing (in terms of effective AOA allowing for dihedral, and effective chord, span and sweep changes due to side slip) are insufficient to overpower the roll effect of the rudder, acting like a vertical aileron. It is not a useful consideration, and rudder should be applied opposite to roll when aileron authority is exceeded as the above scenario is so unlikely.

How this applies to the AA accident I can't fathom...

[Jack1985]

To get rudder reversal

In UsAir 427 I was simply stating what is fact after the actuator jammed it stayed like that for a few seconds before releasing, however reversed, so that the rudder controls had switched - So when the aircraft rolled right the captain immediately took control and applied full left aileron and full left rudder it did not respond and continued to roll as it was jammed right, then when it released he was now applying right rudder even though his foot was on the left pedal - This was probably the most tragic part about that accident.

I only brought that up in a response to a point made by MrSnuggles on page 1, has absolutely nothing to do with 587.

[MrSnuggles]

To everyone it may concern.

Rudder reversal was brought into the thread by my initial reaction to the stated 70 degree bank angle. I admitted to be waay off course but wondered, tounge-in-cheek, if the airplane in question had the same rudder design as f.ex. the USAir 427.

It was concluded that USAir 427 and at least two more planes suffered fatal rudder jams, even rudder reversals as on USAir 427. Here is a link to the Summary from NTSB:
Accident Investigations - NTSB - National Transportation Safety Board (http://www.ntsb.gov/investigations/summary/AAR9901.html)

On the same page you can download the accident report. Click PDF.

[flyboyike]

Really, Jack, I wouldn't worry about it. In fact, if that's your only "serious concern", you're doing pretty good.

[Jack1985]

Well I guess that's good to know! Cheers

[Docbert]

14 January 2014 - An Alaska 737-400 encountered two sudden 70 degree bank angles (both different directions) landing in Vancouver caused by an Air Canada A330, but continued for a safe landing.

Alaska are claiming in a comment (http://www.avherald.com/h?article=46e90ec2) on AVHerald that the bank angle was 20 degrees, not 70.

[Jack1985]

Cheers for that, slightly weird a spokesperson would comment on a public website rather than directly contacting the website hoster. :confused: