PPRuNe Forums - View Single Post - Time for a new edition of "Handling The Big Jets" ?
Old 9th Jan 2010, 17:44
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John Farley

Do a Hover - it avoids G
 
Join Date: Oct 1999
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I would like to suggest that Clandestino is very correct to praise the book in general - but not unreservedly.

The problem with suggesting that a 1976 version still holds good today is that the comment ignores modern fly by wire aircraft. At the risk of teaching thousands of grannies to suck eggs the following diagrams show two very different control systems:





While I have only flown small military FBW aircraft I believe what I want to say is still valid for larger aircraft.

When you are manually flying an aircraft on finals on a nasty gusty day the turbulence will cause the usual variations in bank angle (and perhaps in pitch and yaw) and if the aircraft is a non FBW aircraft you must pretty quickly do what is necessary with the stick (or wheel) to keep the attitude as you want it.

In the same circumstances with a FBW aircraft if shall we say the wing drops a bit you must give the red (feedback) control loop time to correct the attitude back to what it was before the gust. This it will do. If on the other hand you use traditional piloting techniques and skills and stuff in a load of aileron as the wing goes down this will take effect just as the computer is also doing its thing. The sum of these two inputs will put the other wing down and off you go on a nice little pilot induced oscillation.

So in my view it is easy to 'overfly' a FBW aircraft in rough air. Just relax, and use the model in your head that you are an instructor and watching a student perform. We all know we don't like instructors who do not wait for the student to do the right thing and grab it too soon.

Dave's excellent book does not cover these changes. Eleven years after his last edition was published the A320 started flying. Today it has been joined by the A330, A340, A380, B777 and B787.

Last edited by John Farley; 9th Jan 2010 at 18:40.
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