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ANA Japan roll incident.

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ANA Japan roll incident.

Old 30th Sep 2011, 11:57
  #61 (permalink)  
 
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According to the article

ANA said a 38-year-old co-pilot likely hit the rudder trim controls by mistake instead of pushing the door unlock button to let the captain in after he stepped out of the cockpit to go to the restroom.
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Old 30th Sep 2011, 11:58
  #62 (permalink)  
 
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Rudder trim issue according to Flight Global:

VIDEO: ANA 737 rolled near-inverted after rudder trim blunder
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Old 30th Sep 2011, 12:06
  #63 (permalink)  
 
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You have to be careful that when you attempt to fix one problem that you don't generate a load more.

The locked door policy was introduced to prevent unfriendly people easily gaining access to the flightdeck post 9/11.

Trouble is crewmembers now have to go through all this rigmarole just for a comfort break - it's not the first time that the rudder trim has inadvertently been used in this manner.

It's all about risk management and personally I feel the locked door policy carried extra risks.
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Old 30th Sep 2011, 12:14
  #64 (permalink)  
 
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Just an ATCO so excuse me if I'm asking stupid questions, BUT.

Why would you have a button which if inadvertently flicked inverts the airplane?

This button adjusts my range... this button the brightness and this one blows up the building... yeah.
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Old 30th Sep 2011, 12:24
  #65 (permalink)  
 
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Recovery? What recovery? Instincts? Who is kidding who? What else do you expect from pilots who might have 100 hours total time of hand flying when they retire. Much worse is on the horizon I assure you.

Couple the lack of ability with a sense of entitlement and bravado (on the ground and safely ensconced in the bar with his mates) that needs to be seen to be believed, et voilą, you have airliners rolling over on their backs.

If you haven't been in the cockpit with these guys you don't and can't understand. Once you have, it is all made clear.

Where in hell are the insurance companies and ICAO? Forget the so-called unions, management, and complicit regulatory agencies staffed with former company hacks. Don't believe me if you choose, but it all happens to be true.

I await my mandatory tongue lashing for pointing out the obvious.
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Old 30th Sep 2011, 13:27
  #66 (permalink)  
 
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Originally Posted by Short Approach? View Post
Just an ATCO so excuse me if I'm asking stupid questions, BUT.

Why would you have a button which if inadvertently flicked inverts the airplane?

This button adjusts my range... this button the brightness and this one blows up the building... yeah.
The rudder trim is a round dial on the central pedestal. It is not in your direct line of sight unless you purposefully turn around and look at it.

The dial is of the continuous type. Meaning if you turn the dial to starboard the rudder will incrementally trim farther and farther into starboard.

Coincidentally the button to release the locking mechanism of the door is also a dial. It is positioned quite close to the rudder trim dial. Both dials are not in sight of a pilot who has not turned around to look at them.

In practice flight attendants will often call the cockpit to take orders for food or drinks. Sometimes people add last minute things over the flight inter-phone so the flight attendant takes a bit longer than usual to enter the cockpit. Some pilots, especially FO's are vulnerable to this, grab the wrong dial and hold it to the left. If an FO is busy reading, talking to ATC or something else he might inadvertently grab the rudder dial instead of the door dial. Because they are behind him and relatively close to his seat he won't notice this in his peripheral vision.

Holding the door dial to the left unlocks the door mechanism. You need to keep it turned to the left actively to keep the door unlocked for the flight attendant to enter the cockpit.

As you can see from the video the 737 was tipping over to port side. This coincides with my description of the operating principles above.

edit: Oddly enough: even though the dial itself is not visible to the pilot, the displacement of the yoke should be obvious almost immediately. The AP will attempt to balance the increasing out of trim position by applying opposite aileron. This becomes very clearly visible once it goes over a few degrees as the entire yoke would be turning farther to starboard as time goes by.
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Old 30th Sep 2011, 15:01
  #67 (permalink)  
 
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It takes 29 seconds to hold the rudder trim in the 737 full over to obtain full trim from neutral. It is hard to believe that even the most incompetent pilot would hold the switch that long in mistaken belief it was a door unlocking button. Even if he operated the aileron trim by mistake it would take about half as long to obtain full aileron trim and that includes pressing two switches together. Something not quite right here. Another case of the automatic monkey syndrome where lack of basic manual flying skills is practically non-existent in many airlines.
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Old 30th Sep 2011, 15:12
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Another case of the automatic monkey syndrome where lack of basic manual flying skills is practically non-existent in many airlines.
Unfortunately the lack of manual flying skills is very existent ...
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Old 30th Sep 2011, 16:16
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Just a question for the professionals -- The information provided suggests that the plane rolled significantly in excess of 90 degrees, yet the FO was able recover it to stable flight. Does that not suggest that this FO had some pretty good situational awareness and manual (aerobatic, indeed) flying skills? Or would this recovery have been automatic?

PS: it also seems to suggest that the 737 retains a lot of the aerobatic capability (without being torn apart) that Tex Johnson demonstrated in the Dash-80 (707 precursor).
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Old 30th Sep 2011, 16:25
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Originally Posted by Centaurus View Post
It takes 29 seconds to hold the rudder trim in the 737 full over to obtain full trim from neutral. It is hard to believe that even the most incompetent pilot would hold the switch that long in mistaken belief it was a door unlocking button. Even if he operated the aileron trim by mistake it would take about half as long to obtain full aileron trim and that includes pressing two switches together. Something not quite right here. Another case of the automatic monkey syndrome where lack of basic manual flying skills is practically non-existent in many airlines.
I tend to disagree here.

29 seconds is not a very long time. Very often the attendant or other pilot calls to gain access but takes some time to actually open the door. I've seen this happen quite a few times already. People just hold the switch to the left and keep it there until the other person actually opens the door.

I'm not sure why you are talking about aileron trim.
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Old 30th Sep 2011, 16:53
  #71 (permalink)  
 
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29 seconds is not a very long time.
Pilot calls to re-enter cockpit. The one on deck reaches over to turn the unlock knob. The one outside jiggles the door. Still locked, calls again (now a bit pissed). The one inside thinks to himself (while still holding the wrong control), "Dumbass. Can't even operate a doorknob." I can see 29 seconds passing with such antics.
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Old 30th Sep 2011, 17:16
  #72 (permalink)  
 
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Yup, 29 seconds is no all that much. And the control column displacement is not necessarily within primary field of view if the FO is trying to see something on that tiny CTTV screen on the left aft overhead panel (which means he is hanging out of his seat halfway across the center pedestal staring behind and to the left side) where he has to continuously check to make sure the area in front of the flight deck door is clear.

By the way, he didn't use full left rudder trim, it was just two left trim inputs each lasting a pretty short time, that was all it took. Check out the first report which is sadly in japanese but clearly shows some of the FDR data as well as the flightpath and center pedestal of this configuration.

For someone with supposedly no manual flying skills he did a pretty fast recovery though, during night without anticipating any upset. Not bad on that at all, while of course the initial action wasn't great but not all that surprising in that 40 years old flight deck, designed without much knowledge about ergonomic man-machine interfaces.
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Old 30th Sep 2011, 20:34
  #73 (permalink)  
 
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Wouldn't have happened on an Airbus. Ground the Boeing !!!
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Old 1st Oct 2011, 00:32
  #74 (permalink)  
 
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I'm at risk of sounding like Mr Angry here, but I am reading a lot of excuses for some pretty rubbish piloting skills.
Most of the controls on that panel are within 10cm of the rudder trim. The two controls in question are a different size and shape.
If you haven't a clue where the switches are by feel, go sit in the cockpit for hours and practice the muscle memory.
If you don't know where the switches are, look. It's not as if he was doing night AAR or anything busy.
If he wasn't looking at the panel, then why wasn't he looking at the instruments?
29 seconds IS a long time.
Coupled with AF447, I would love to know why incompetence of this level isn't being spotted earlier (e.g. in the sim)
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Old 1st Oct 2011, 00:55
  #75 (permalink)  
 
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I for one I'm not too quick to crucify, not going to get into a deep discussion of security sensitive procedures but it is not uncommon to be holding that switch for a while because your partner turn around to answer a question from the CA, it only takes a few seconds of being distracted not to notice that the ailerons are deflecting in the opposite direction to compensate until the AP gives up and then all of a sudden he found himself in an almost hard over rudder situation, single pilot, without enough tolerance in a specific orifice to put a needle trough and this didn't turn into a smoking hole on the ground, we all know that some rudder events weren't that lucky and this was with two pilots working the problem. It is not that I am not critical of the event, I'm just looking at it from the perspective that this paid hobby of ours teaches very heavy handed lessons.

Next time you are doing recurrent, most of the times one finishes early right? tell the checker running the sim to climb you to 350 and then while you are turned looking at the back of the sim, do the same thing, operate the rudder trim until the A/P disconnects, I know it is not a true test because you are expecting it and he wasn't, but it will give you an interesting perspective as to how easy this could have ended in tragedy.
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Old 1st Oct 2011, 07:17
  #76 (permalink)  
 
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I tried it in the sim yesterday. Shocking how easy it is to get in an upset like that.
BTW, a few posts back there is a photo of a 737 pedestal. Our pedestal is built up in such a way that the door knob and the rudder trim are directly next to each other.
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Old 1st Oct 2011, 07:59
  #77 (permalink)  
 
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Just a reminder (for "fin fly" and "short approach" and others):

The 737 (like most multi-engine planes) has a very powerful rudder for yaw control with an engine failure, which can indeed turn a plane upside down and (via the inverted lift) point the nose at the ground very rapidly if activated unexpectedly.

Search the Web for "United 585" and "US Air 427" to find two fatal 737 crashes caused by a rapid roll brought on by uncommanded rudder deflection (in those cases, a mechanical glitch, rather than reaching for the wrong knob).
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Old 1st Oct 2011, 11:13
  #78 (permalink)  
 
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The low-tech solution posted earlier on another thread is still relevant so I apologise only to those who have already seen it.
Pilot wishing to leave the flight deck calls the FAs and waits until one appears at the cockpit door, enters the code and is allowed into the flight-deck. Pilot leaves and door is locked behind him.
Pee and chat take place for a few minutes until the pilot enters the code and the FA looks through the peep hole and the seated pilot confirms via camera, if fitted, that it is indeed the pilot outside the door. Now the safe part, the FA opens the door by using the door handle!
Result, no stupid switch position will ever catch you out again.
Cost; zilch.
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Old 1st Oct 2011, 11:17
  #79 (permalink)  
 
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i believe there's definately more to this..... hopefully they come out with a full investigation and report.

normally, if you flick the switch and open the cockpit door, after a while.. if the other crew member doesn't come in, would you keep holding it? or let it go? i would let it go and check the camera to see what is he doing.

i don't know bout the 737s... i fly the A320.. and when i flick the open door switch, i'll hear a loud "Tack" indicating that the door strikers are unlocked.
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Old 1st Oct 2011, 12:09
  #80 (permalink)  
 
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I flew the -200 & -300 and all we had was a push button to lock/unlock the cabin door. WHEN did they change this switch and WHY ?!?!
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