PPRuNe Forums - View Single Post - Automation Bogie raises it's head yet again
Old 28th Dec 2010, 18:28
  #43 (permalink)  
Loose rivets
Psychophysiological entity
 
Join Date: Jun 2001
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There was a guy on the NOVA?? or some such program, who showed us what he would have liked the 447 PF to be doing. He suggested 5 degrees nose up, and a specific power setting. Clearly, this is only the start of containing the situation.

The two and four engined turboprops I flew were all much of a muchness in terms of basic control, but when on a slippery jet, it was quite a different story. One thing on the BAC 1-11, was the unpleasant resonant frequency of the wings. They really would twang sometimes, and the FD 108 would become a vertical bar of colours for several seconds. This made accurate interpretation of the pitch very difficult if not impossible in the short term. Needless to say, this could be repeated over and over for several minutes and there were times it seemed automation might be able to do a better job. However, there was one thing the sensors didn't take into account, and that was vertical acceleration.

Firstly, I have to say I don't know if modern kit inputs vertical acceleration data.

I know we have it drummed into us to forget seat-of-the-pants flying, and believe the instruments, but in our scenario, we are already down to basics. Suggesting a set pitch and power leaves me a little worried. I found anticipating the power needed, by the feel of the vertical acceleration was something that put me ahead of the game. There is no way in hell you can look to EPRs, HP rpms or N1s for such human input, it has to be initiated very quickly and with only moderate accuracy.

I hasten to add, this movement had to be contained within a small range.

Throttle position was available and meaningful to us on those simple machines, and when I read of throttles that don't move, and of insistence on A-T, I just feel glad I was flying in a different era. And what is also obvious, it needs the kind of practice a box fixed to the planet can never provide. Pilots must be allowed to fly their aircraft on a regular basis - especially in rough air.
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