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Old 24th Aug 2011, 12:04
  #3210 (permalink)  
Rananim
 
Join Date: Sep 1999
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The truth hurts but you need to look closer to home for this one. It is the mark I human being at fault, nothing else.
Safety Concerns

I hope by "human" you meant to include the designers because if not,its grossly unfair to the pilots.Are you really saying that the interface design contributed nothing to the probable cause whatsoever?
An experienced Airbus pilot left a post saying how sensitive SS control was at even low altitude.What about high altitude with little buffet margin and throw in moderate(perhaps worse) turbulence..what then?How easy would it be to overcontrol then?The forearm must rest on an armrest with the wrist as the pivot point for SS control in an Airbus.Great for small precise control inputs in smooth air.But what about during a high alt upset in rough air when the forearm might become dislodged.The stick isnt between your legs,its off to one side.
And then theres no feel feedback.And the PNF cant see what the PF is commanding on the stick.Hes out of the loop so its effectively a single crew response.The PNF can override and try his luck but theres no way for both pilots to work it in tandem.They can override each other or they can work in opposition with the computer adding the inputs algebraically or cancelling each other out.And who knows who's really in control?The "priority" audio call and the visual green/red arrow on the glareshield might be fine in a normal situation.But in a bad situation with turbulence and with loads of ECAM warnings?These channels get dumped quickly.You just wouldnt get this in a conventional aircraft.YOU SEE BOTH STICKS.YOU SEE WHAT THE OTHER GUY IS DOING WITH HIS STICK.YOU WORK IT TOGETHER IN EXTREME CASES WITHOUT ANY NEED FOR AUDITORY/VISUAL FEEDBACK.ITS ALL TACTILE.

And then the autotrim cutting out with THS at max ANU.Do you think pilots have time in a bad situation to look at the ECAM and start deciphering what effect the changing laws have on what theyre doing?If they can remember.ALT LAW..right, I have no stall warning protection.ABNORMAL LAW..right, trim is manual.THEY FLY THE PLANE FIRST AND FOREMOST.And the stall warning inhibit?Going off when the aircraft was in a deep stall?This is acceptable design is it?All this complex and frankly suspect interface design didnt have any effect whatsoever on the outcome??

The Airbus is a video game,nothing more.In normal ops,Im prepared to believe its the most wonderful thing since slice bread.
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