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Old 16th Aug 2011, 09:13
  #2921 (permalink)  
Gretchenfrage
 
Join Date: May 2005
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from Safety Concerns

The biggest problem here is analogue pilots flying digital a/c. And by that I do not mean remove the pilot from the cockpit but after more than 40 years of digital a/c that have more than proven their safety capabilities it is about time pilots stopped harping on about "old" a/c and moved into the 21st century.

The a/c are sound, the technology is sound, room for improvement yes. The A320 for example is actually one of the safest commercial airliners flying despite all the doom and gloom and the first lightning strike will send it spinning to the ground out of control crap that is often brought into the same sentence.

A lot of pilots criticising Airbus are quite used to digital flying. They operate EFIS and FBW aircraft as well, simply from other manufacturers. So your first point is polemics.
Second, such an aircraft is actually the safest, the T7, therefore the whole discussion about the Airbus layout has a point, as there is just as modern an aircraft flying that is, at least at the moment, even safer. So your second point is none.

Here are a few comment and questions from a recent meeting:


Some traps in the Airbus philosophy:
The dead stick on the PNF side (or on both with AP on).
If a PF starts losing it, be it a simple PIO or as here with stress-motivated and effectless swinging around the stick, the PNF, in order to realize, must look over and observe the PF.
This is a waste of concentration, he should be monitoring the instruments. With a moving stick (or yoke), he could continue to monitor instruments and simultaneously would be realizing the PFs error, through his second, tactile input channel. Additionally if he wanted to intervene, he could exerce force on the stick and by that raise attention of the PF, again through the second channel. The first one is quite often absorbed by the situation and trying to talk to a stressed PF is futile, the audio channel is the first to leave us under stress.
Why no feedback?

The fixed Autothrust Lever
The Airbus lever is set in a detent, this applies as well when the AT disconnects. When this happens, the AB pilot needs to realize the ECAM warning. With a moving lever, the disconnected, stuck and no more moving AT sort of warns the pilot additionally through the tactile channel. Furthermore the lever will be in the exact position of the thrust. Not so in an Airbus. The lever is still in the detent and the thrust where it was last. The Airbus philosophy tells us, that when the AT is disconnected, the lever acts like a conventional one, position equal thrust, but in the bad case of an automatic disconnect, this is not true. The pilot has to un-detent the lever to get the correct position vs. thrust ratio. This is an unnecessary additional step in a high stress situation.
Why fixed levers, what is their advantage (pls don’t come up with the weight issue)

THS
As I understand, the THS was following the PFs inputs right up to full aft, even though the stall warning was active. On Boeings the stabilizer is inhibited to move further aft when stall speed is reached.
Why can an Airbus THS?

Stick shaker
Where is it on Airbus? One of the most direct warnings, going directly through the hands right into the spine and brain seems to be missing. A whole channel missing.
Why?
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