Originally Posted by
Talkdownman
There is NO GUARANTEE at all that an aircraft its own nav will follow its planned track.
This is the point I was trying to make about changing the way we work. You believe the above to be true. I totally disagree, the above just a rule and liability issue. Just because you have said "Heading nnn" the chance of us deviating remains unchanged although one could argue it is actually increased. When given "Direct xxxxx" we do just that. We don't wander around the sky for the hell of it, we just let the plane follow the magenta line. And believe me it follows it. Changing wind speed or direction, changing airspeed makes no difference the straight line track (OK, Great Circle) followed across the surface of the will alter the track by a few metres or so. Providing of course we have pressed NAV. Besides, our clearance is to go 'direct to xxxxx' and if we want a variation we have to be cleared. We also have to remember to press HDG if given one. So using your "guaranteed" method you believe you get what you want, but it's just an illusion of control. The downside of micro-managed headings is the constant R/T. Give us a "Direct xxxxx", one readback or CPDLC confirmation and that's it.
PM