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Airbus trepidation... convince me otherwise!

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Airbus trepidation... convince me otherwise!

Old 22nd May 2012, 21:27
  #161 (permalink)  
Join Date: Jul 2002
Location: UK
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The trick with understanding the FBW Airbus is to realise that the test pilots and engineers who designed it elected to come at airliner operations from the standpoint of the technology available in the early '80s. If something you expect to be there isn't, it's because it's done in a slightly different way.

The reason the sticks aren't interconnected was because they simplified the hardware aspect of the flight deck design. In normal operation only one pilot is supposed to be in control at any given time. Because the controls are fully-hydraulic, the need to use more muscle power on the stick/yoke is not there. The upshot of this is that if your colleague in the other seat suffers an incapacitation, you can take and hold control with the override button and don't need to physically move them until the situation is resolved. This means that when monitoring, you are monitoring the instruments rather than control deflection - but most of those I've spoken to have got fairly used to this.

The same goes for the thrust levers. The actual thrust setting is visually displayed on-screen rather than by physical position - this also can take some getting used to, but most have had little to no difficulty adjusting.

Autotrim is not to be feared - it's simply a logical follow-on from the design of the rest of the system. Either you or the automatics command a pitch angle and the aircraft will trim itself to match. What needs to be borne in mind when discussing AF447 is that the autotrim responded to the PF holding full back stick for almost a minute during a time when the protections were unavailable - the question that everyone's trying to answer is why he did that.

The bank angle and alpha protections only kick in at the edge of the safe flight envelope - it wouldn't surprise me if you never ever encounter them. Contrary to what you may have heard, none of the protections will cause a positive change in attitude opposite that which the pilot orders - the only positive command to come from the protections is the thrust being set to TOGA in Alpha Floor. Everything else just maintains your order at the safe maximum for the airframe.

Another common misconception about the Airbus FBW flight deck was that it was designed by managers, engineers and us computer geeks without pilots getting a word in. Needless to say, this is complete garbage. The engineering and test pilots who worked on the programme were among the best in the world and nothing got through without their say-so.

The Airbus FMS setup is not actually a massive leap over that fitted to the 757. As such it is very important to keep the concept of automation and the concept of FBW separate and distinct in your head. Going on the evidence, Airbus are no more wedded to the concept of automation than any other manufacturer.

But dont take it from me, take it from 757 captain and rock legend Bruce Dickinson:

Last edited by DozyWannabe; 22nd May 2012 at 21:28.
DozyWannabe is offline  
Old 22nd May 2012, 22:03
  #162 (permalink)  
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Wheelie Boeing thingy, my dear chap.

I have been flying Airbus FBW for 7 years and stand by my comments - which stem from my experience.

Perhaps I could have written a clearer post, or gone in to much more detail, but my purpose was to try to reassure the thread starter not to be so scared of the FBW Airbus. There is a lot of nonsense paraded about it.


Uplinker is offline  
Old 23rd May 2012, 01:02
  #163 (permalink)  
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Ultimately the short answer is that you have nothing major to worry about. Your training captain should be able to answer most of the questions you have, and if you're still worried after that, there are more than a few on here who can answer too (I know for a fact that there are several Airbus FBW line pilots and at least one TRE).

Change from what one is used to is always something of a hump to get over, but I'm certain that before you know it you won't even be thinking about it.
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Old 23rd May 2012, 22:39
  #164 (permalink)  
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But... I still question: Are the pilots REALLY in control? I had a lot of difficulty watching the engine instruments register changes without the throttles moving. I never quite knew what the engines were doing. Why are the throttles locked at Climb Thrust with the engines back at idle? This stuff really conflicts with my "Boeing-warped" mind.

I also had a tough time comparing aircraft pitch/roll commands without seeing a corresponding stick movement. Why, because the other stick doesn't move. How does the other pilot know what the flying pilot is doing?
Yes- Airbii pilots in control..

If you can't see or undertand that then YOU A R E STUPID
White Knight is offline  
Old 24th May 2012, 00:05
  #165 (permalink)  
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@White Knight:

Your second statement is a little harsh. There's a lot of misinformation out there about the A320 and her descendants, and a lot of it seems plausible until you do a fair amount of digging - to the extent that a lot of people believe it and repeat it without checking.

Regarding the part you quoted, the A320 system (other than the moving levers), is essentially the same as the FADECs in the 757 and 767 under the hood - but the feedback regarding actual thrust setting is rendered by a screen rather than electric motors moving the levers.
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Old 25th May 2012, 16:07
  #166 (permalink)  
Join Date: Nov 1999
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I agree. No need for that White Knight.

Another way of looking at it is to remember in the 1970's when cars had manual chokes. We were all used to adjusting the choke and accelerator to get the engine started on a cold morning. Now, with electronic engine management and fuel injection - cars just start and run - every time ! Yet we don't miss fiddling around with the engine controls just to keep it running do we ?

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Old 25th May 2012, 17:05
  #167 (permalink)  
Join Date: May 2000
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Oh good heavens here we are again...

If as a professional pilot you believe that T/L movement tells you what your thrust is....... I would rather fly with someone else. All competent pilots include EPR/N1/RPM/whatever the dial says, in their scan.
Imagine engine failure on approach in a 737 - moving thrust levers will both move forward - but does that mean that thrust has increased on both engines? No.
You don't know what is happening until you look at the dials.
TyroPicard is offline  
Old 27th May 2012, 13:21
  #168 (permalink)  
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Trust me - you will get used to it all.
Natstrackalpha is offline  
Old 27th May 2012, 17:09
  #169 (permalink)  
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Airbus trepidation... convince me otherwise!

You cannot acquire new experties if you are phobic. A320 is the most poular and preferred a/c in its category. Last year airshow A320 bagged more than 900 orders and its rival 737 nil, yes zero. I switched on to this FBW after being a 747 classic captain. Offcourse I enjoyed flying the big bird. I found absolutely no problem in change over because I carried no preferrences or prejudices in the new cockpit. Just open mind. Automatics are way of modern life. If you enjoy horse riding so much then stick to it. But you can always learn to drive a car. While learning new technique don't compare. When you acquire enough time on this one then you can. Enjoy the transition.
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