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AF447 final crew conversation - Thread No. 1

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AF447 final crew conversation - Thread No. 1

Old 27th Jan 2012, 09:56
  #1181 (permalink)  
 
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@Golf-Sierra:

They have missed all the clues.......

Looking at the video @ 02:47: the SS order visuals are engaged on the PFD at touchdown.

Would it be an enhancement to show this for the PM only, in flight and only if PF SS released
from locked state (@A/P disconnect), so he can observe what his PF is doing with the SS?
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Old 27th Jan 2012, 12:13
  #1182 (permalink)  
 
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In reference to last last video, does anyone else think there was a lot of side stick action going on? I never flow an Airbus, just an old Douglas.
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Old 27th Jan 2012, 13:26
  #1183 (permalink)  
 
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If there are any doubts if the pilots would be aware that the aircraft is automatically setting the trim nose up - please have a look at this video. Those wheels are painted alternating black and white for a reason.
Ask most Airbus pilots if they actively see the trim wheel moving and the answer will most likely be "No". It moves silently - unlike the Boeing system - and it is so effective in normal operations that it's not actively monitored. In an airplane that is supposedly out of control for "unknown" reasons, it may not be intuitive to look at something you don't normally see.
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Old 27th Jan 2012, 13:34
  #1184 (permalink)  
 
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Originally Posted by Golf-Sierra
If there are any doubts if the pilots would be aware that the aircraft is automatically setting the trim nose up - please have a look at this video. Those wheels are painted alternating black and white for a reason.
That camera angle put the trim wheel in evidence but this is not something a pilot easily catches when attention is on the flight instruments and/or outside.

To think that the pilots on AF447 should have seen that wheel moving under the conditions is not realistic.
More than anything that wheel should not have turned at all under STALL WARNING.
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Old 27th Jan 2012, 13:56
  #1185 (permalink)  
 
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Originally Posted by A33Zab
Would it be an enhancement to show this for the PM only, in flight and only if PF SS released from locked state (@A/P disconnect), so he can observe what his PF is doing with the SS?
Never in this world it would happen :
Airbus would have to acknowledge it is better for a PM to know what's going on the other side ...

Also, IMO, the PFD is sufficiently loaded as it is right now to have another graphic element to process through the pilot's eyes.
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Old 27th Jan 2012, 15:20
  #1186 (permalink)  
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Let's not make this any more complicated than it need be. If, as it seems, we need to help an 'above-average' AB crew recover from this situation through software, let's make it Conf's screen at post # 1187, or with my flashing downward arrow on the EADI. I would suggest taking away the arrow at the top of the 'speed' red bar too. It is, after all, primarily AoA we want under control.
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Old 27th Jan 2012, 15:51
  #1187 (permalink)  
 
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In reference to last last video, does anyone else think there was a lot of side stick action going on?
Yes....there was a Very Frequent Poster in these threads, I forget who, who kept calling Bonin's SS technique "stirring the mayonnaise." It should be reminded that such a technique is much more dangerous/critical at high altitude/speeds.

That's all I know.
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Old 27th Jan 2012, 17:41
  #1188 (permalink)  
 
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grity posted his original capture of Bonin's "stirring the mayonnaise" technique in June 2011, and again in post #431 - AF447 Thread No.7. As grity points out, Bonin's movements weren't fast enough to actually make mayonnaise!

jcjeant
may have coined the phrase in these threads, but one has to wonder whether it is the visual search for reaction clues, rather than real SS feedback that leads to the "stirring" technique.
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Old 27th Jan 2012, 18:16
  #1189 (permalink)  
 
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@mm43
jcjeant may have coined the phrase in these threads, but one has to wonder whether it is the visual search for reaction clues, rather than real SS feedback that leads to the "stirring" technique.
That's the first time I've read that idea here, and it certainly makes a lot of sense. A complete lack of physical feedback on those sticks, artificially generated or not. I remain convinced that those joysticks are dangerous in the hands of the under-trained.

CUE: AB pilots saying "nonsense!"
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Old 27th Jan 2012, 20:15
  #1190 (permalink)  
 
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Yes....there was a Very Frequent Poster in these threads, I forget who, who kept calling Bonin's SS technique "stirring the mayonnaise." It should be reminded that such a technique is much more dangerous/critical at high altitude/speeds.
The pilot appears to be moving the stick quite abruptly. I think this looks strange to some extent because of the wide angle lens being used, and also the fact that the camera is attached to the airframe. The extreme lens perspective makes the plane's flight appear extremely smooth. I think that if a more normal lens were used, perhaps handheld, we would see that there is some turbulence, the flightpath is in fact not quite so smooth and that the stick movements are not extraordinary.

Besides - Boeing pilots seem to move their yokes around quite a bit as well, see around the 5:00 mark: Cockpit video - Boeing 737-200 - landing at windy Cancun, Mexico. - YouTube

If SS 'stir the mayonnaise', what do yokes do? Tumble the laundry?
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Old 27th Jan 2012, 20:45
  #1191 (permalink)  
 
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What are the clicking noises in that video, please?

Just interested.
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Old 27th Jan 2012, 21:07
  #1192 (permalink)  
 
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Mayo

"...mayo...". A glib, meaningless soundbite.

It would be a refreshing change if people would only offer comments and judgements on things they have any actual experience or knowledge of.
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Old 27th Jan 2012, 21:57
  #1193 (permalink)  
 
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chrisN,

haven't watched the video, but older 737's with the "paddles" to engage the autopilot have an endearing habit of emitting clicking noises from the paddles when controls are moved (useful clue to the other guy that you are still alive) perhaps Airbus should introduce something jurassic but similar on the "playstation" models,always useful to know if the other guy is stirring the porridge more than required
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Old 27th Jan 2012, 23:12
  #1194 (permalink)  
 
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Originally Posted by captplaystation View Post
chrisN,

haven't watched the video, but older 737's with the "paddles" to engage the autopilot have an endearing habit of emitting clicking noises from the paddles when controls are moved (useful clue to the other guy that you are still alive) perhaps Airbus should introduce something jurassic but similar on the "playstation" models,always useful to know if the other guy is stirring the porridge more than required
Similarly, I seem to have remarked repeatedly on my confusion about why the 'bicycle bell' on the pitch trim wheel has disappeared. Equally 'Jurassic'', but it did the job.
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Old 28th Jan 2012, 00:35
  #1195 (permalink)  
 
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Watching that video either the pilot was spastic or that is the normal way to fly by side stick. I had one ex Buf, B52 pilot,fly like that with a yoke but no one else. Normal pilots don't move the controls unless a correction is required, they don't move it all over the place for no reason.
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Old 28th Jan 2012, 01:33
  #1196 (permalink)  
 
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Watching that video either the pilot was spastic or that is the normal way to fly by side stick. I had one ex Buf, B52 pilot,fly like that with a yoke but no one else. Normal pilots don't move the controls unless a correction is required, they don't move it all over the place for no reason.
I'll probably get shot down by a real 'Bus pilot, but as I understand, that stick deflection in the 'Bus is essentially commanding a rate, not a control deflection. Zero control deflection equals zero rate.
As such you would be pulsing the control rather than applying a pressure.
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Old 28th Jan 2012, 05:24
  #1197 (permalink)  
 
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Stirring the mayonnaise

It seems the pilot in the video is used to making lots of jerky control inputs when he flies, here's a video from when he was flying the F100.

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Old 28th Jan 2012, 11:20
  #1198 (permalink)  
 
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This captain then lets go of the controls after nose wheel contact with the ground. Oh well. I suppose he is done flying the thing even though he is going at least 100KTS on the ground.
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Old 28th Jan 2012, 11:28
  #1199 (permalink)  
 
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Pardon a non ATPL interjecting, but I would naively have thought that after the nosewheel is on the ground, my attention would switch to throttles/brakes/spoilers/nosewheel steering - none of which are operated by hands on the yoke?
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Old 28th Jan 2012, 11:34
  #1200 (permalink)  
 
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The nose wheel is still operated by the pedals however the authority of the pedals in relation to the nose wheel is reduced. All other items you mentioned are operated by the other hand. Check out that other video posted above. That is (In my opinion) the correct procedure. If there was any kind of a crosswind the controls would (should) have been used to counter the cross wind. ALL of them. By the way the control movements in the 73 may seem excessive (I don't really think so) but they were no way even close the the other captain flying the F100 or the AB. Again my opinion. BTW this is not ATPL stuff, this is basic C150 technique. Forgive me please in hijacking the thread.
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