PPRuNe Forums - View Single Post - How Do you "Lock On" to an altitude with Glass Cockpit
Old 29th May 2012, 15:42
  #17 (permalink)  
alf5071h
 
Join Date: Jul 2003
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Mach, I disagree with the majority of the arguments calling for greater focus on manual flying skills; not just the view in #17.
Recent accidents indicate that the human problems were predominantly due to the choice of action, and not that the crew couldn’t fly the aircraft. In many cases the aircraft was flown (accurately) into the wrong part of the flight envelope. I exclude AF447 because there may be other system and trim issues, and we don’t have all of the details yet.

Choice of action requires good situation awareness. With inaccurate situation assessment, then flight control inputs for a chosen action might be hesitant, or exploratory – getting a feel for the situation. The resultant aircraft motion may not match the predictions from the pilot’s understanding.
With good situation assessment, choosing an appropriate action should result in a high probability of success even if the flying is not particularly accurate. Furthermore this action should change the situation to something which was expected, thus confirming the choice – thus a need to continuously reassess the situation.
Training for this should also involve how to combat surprise and 'getting back into the loop'; changing from passive monitoring (automation) to active awareness and control (manual).

Flight instruments provide a major contribution to awareness. A danger with modern displays is that single cue or automatic flight may result in an expectation of ‘single-source’ recovery in abnormal conditions (instant answer).
Good instrument flying skill (awareness) involves scanning a range of instruments, and the construction a time based model of what has happened, what is happening, and what might happen; past, present, future. These snapshots are combined with previous knowledge to provide a mental model – the situation.

Whilst modern displays provide very good inputs to this process for navigation (includes time), it might be questionable if the aircraft handling parameters (speed, attitude, altitude) are as good as conventional ‘dial’ instruments. In particular, note the weaknesses in rate information, this is a critical timeline input to the mental model.
Poor situation awareness due to these aspects may also result in poor timing of the control inputs – sharp / harsh movements – getting the feel for or generating a new understanding of the situation as much as for the aircraft response. This might be interpreted as poor flying skills, but the cause is elsewhere.
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