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Hand flying in todays jet transports

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Hand flying in todays jet transports

Old 29th Mar 2018, 13:34
  #181 (permalink)  
 
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Like we've said, now that the detailed information is out there.

What I really enjoyed was the AMTP training briefing was given old school style by a teacher standing up and explaining things in an easy to understand manner. So much better than staring at a CBT sterile computer screen with equally irritating voice.
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Old 29th Mar 2018, 14:19
  #182 (permalink)  
 
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Originally Posted by RetiredBA/BY
My two penneth!
[...]

So BA has an engine failure in a 320 but the captain was unable to control airspeed, or so I read, no surprise there if pilots are not allowed to use manual thrust but can despatch with inop auto throttle. Bizarre.
Quite. Another irony of any ban on use of manual thrust on the A320 family is that, once engaged, it is smooth and responsive, with none of the hysteresis that we used to experience on non-FADEC jets like the B707 (JT3D), VC10 (Conway), BAC 1-11 (Spey), DC-10 (CF6-50) and even, IIRC, the A310 (CF6-80). That applies, BTW, to both the CFM and IAE engines.

Finally, IMHO, use of A/THR in single-engine flying is not to be recommended. Why would you want to couple an engine failure with an introduction to the extra mental load of using manual thrust? So much easier if you're in practice.
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Old 29th Mar 2018, 15:10
  #183 (permalink)  
 
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The videos are out there. In the videos CA Vandenburg specifically talks about cautious use of rudder at high AOA and low airspeed if more roll authority is needed.

He says “keep in mind this is also the steps for spin entry” or something like that. So it was not a flippant “just do it” recommendation.

What the sim model did was put the aircraft in an unrealistic attitude for a wake turbulence encounter. I forget the entry parameters but it was significantly nose high and recovery required approaching 90 degrees of roll to recover the nose towards the horizon. The NTSB animation of the 587 accident shows rolls of less than 10-15 degrees.

The manufacturers are leery of AAMP because they don’t see the exposure (actual occurrences) in airline flying. The concept is valid but the actual need might never occur. But inappropriate application is a threat.

Last edited by misd-agin; 29th Mar 2018 at 15:12. Reason: Typo
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Old 29th Mar 2018, 15:18
  #184 (permalink)  
 
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Originally Posted by Chris Scott
Quite. Another irony of any ban on use of manual thrust on the A320 family is that, once engaged, it is smooth and responsive, with none of the hysteresis that we used to experience on non-FADEC jets like the B707 (JT3D), VC10 (Conway), BAC 1-11 (Spey), DC-10 (CF6-50) and even, IIRC, the A310 (CF6-80). That applies, BTW, to both the CFM and IAE engines.

Finally, IMHO, use of A/THR in single-engine flying is not to be recommended. Why would you want to couple an engine failure with an introduction to the extra mental load of using manual thrust? So much easier if you're in practice.
All auto throttle systems ‘hunt’, forward, back, forward, back, ad nauseum, in gusty conditions or summer thermals while on approach. And can, does, and will go to low thrust settings a pilot wouldn’t select manually at low altitudes while on final approach.

They’re great systems but they aren’t perfect.
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Old 29th Mar 2018, 15:50
  #185 (permalink)  
 
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Originally Posted by misd-agin
All auto throttle systems ‘hunt’, forward, back, forward, back, ad nauseum, in gusty conditions or summer thermals while on approach. And can, does, and will go to low thrust settings a pilot wouldn’t select manually at low altitudes while on final approach.

They’re great systems but they aren’t perfect.
Agreed. And the other problem with using A/THR for asymmetric approaches on a FBW Airbus is the lack of thrust-lever ("throttle") movement with thrust changes. (We lost that argument with AI in the mid-1980s.) So resting your hand on the throttles provides no tactile warning when the A/THR changes the thrust.

Can't speak for others, but my simple brain was just about capable of remembering that if, for example, the R/H thrust lever is going (or being driven) forward, I'm going to have to consider pushing my right foot forward a bit too.
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Old 29th Mar 2018, 20:34
  #186 (permalink)  
 
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Originally Posted by blind pew
IIRC the investigation data was based on rudder position and there was some doubt as to whether it was pilot error and not a software problem. .
You do not recall correctly, or may have never known. At any rate, in addition to the rudder position data, there is *also* rudder pedal position data, coming from sensors located very close to the rudder pedals. If you read the report, the NTSB They did extensive examination and testing of all components which conceivably could have commanded rudder motion
All information points to it being pilot input, and I don't recall any information which suggested that it was not. Like a lot of things in aircraft accident investigation, there's not absolute 100 percent certainty, but they found no indication it was other than pilot input, and they looked hard to find such.

Last edited by A Squared; 31st Mar 2018 at 05:31.
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Old 30th Mar 2018, 10:01
  #187 (permalink)  
 
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Rudder position data

No never knew that that was recorded.
I avoided the bus and none of the six types I flew had that capability.
But it posses another question in that is there rudder pedal feedback from what the rudder is doing?
This was the case on a couple of aircraft I flew but not on the VC10 which is the kite I declared a May day on. We were in the dark as to why the aircraft was in self destruct mode and it was only when I switched the autopilot off to see if I could control it as a last resort that I realised it was a run away damper.
My previous aircraft one could feel what was being commanded through the controls.
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Old 30th Mar 2018, 20:25
  #188 (permalink)  
 
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Originally Posted by blind pew
But it posses another question in that is there rudder pedal feedback from what the rudder is doing?
Well, not an Airbus systems expert by any means, but I have done a fair amount of reading on the investigation of the AA crash. The A300 is not a Fly-By-Wire airplane like the later A320 series. There is a mechanical link between the rudder pedals and the rudder control. That said, if I understand it correctly (and I may not) , rudder motions commanded by the yaw damper are isolated from the rudder pedals by the differential control unit which blends yaw damper input and rudder pedal input. So, if that is all correct, then the fact that the Flight Data Recorder recorded rudder pedal movements in synch with the rudder movements, that seems to strongly suggest that the rudder movements were not commanded by the Yaw damper. As I understand it, all rudder movements which were not commanded by the pilot are commanded through the yaw damper.
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Old 31st Mar 2018, 09:19
  #189 (permalink)  
 
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The Airbus safety conference just gone had a big chunk of it devoted to the rudder and reinforcing the advice on not to use it during wake turbulence.

The detailed info should appear in time in training departments from those airlines present.
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Old 5th Apr 2018, 21:08
  #190 (permalink)  
 
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Originally Posted by Pugilistic Animus
Every airline should keep and Old 707 just for live practice all the way to 2 engines out on one side...250 hours in the 707

That will get their hearts right with jets, for sure
I love this. I spent my first 16 years flying KC-135s and B707s. My last 10 was in the left seat of an A320 which I usually let the computer fly, but then I already knew how. Most of my FOs hand flew a lot since my airline encouraged it and the union demanded the right.
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Old 6th Apr 2018, 00:02
  #191 (permalink)  
 
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Nice idea the 707 but you can achieve the very same thing with a 737-200.Lots of them still around.
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