Airbus FBW family - flight plan predictions
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Joined: May 2003
Posts: 9
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From: UK
Airbus FBW family - flight plan predictions
Please would anyone advise:
When a flight plan is first loaded and altitude constraints are shown the intervening waypoints altutdes are then predicted.
In the climb phase will a predicted altitude ever be higher than a subsequent constraint?
Similarly on descent will a predicted waypoint ever be lower than a subsequent constraint.
The answer would seem obvious (that a smooth path is always predicted) but I have been advised that this is not always the case.
Many thanks
When a flight plan is first loaded and altitude constraints are shown the intervening waypoints altutdes are then predicted.
In the climb phase will a predicted altitude ever be higher than a subsequent constraint?
Similarly on descent will a predicted waypoint ever be lower than a subsequent constraint.
The answer would seem obvious (that a smooth path is always predicted) but I have been advised that this is not always the case.
Many thanks
Joined: Jun 2001
Posts: 1,178
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From: UK
It all depends on what the entered constraint requires.
If, during the climb for eg, the constraint is a minimum altitude by point x, but the aircraft can achieve higher, then the prediction will be higher than the constraint. Similar, but in reverse of course, for the descent.
If the constraint requires 'AT' a particular height (and it's achievable!) then prediction will be exactly that.
Hope this helps.
If, during the climb for eg, the constraint is a minimum altitude by point x, but the aircraft can achieve higher, then the prediction will be higher than the constraint. Similar, but in reverse of course, for the descent.
If the constraint requires 'AT' a particular height (and it's achievable!) then prediction will be exactly that.
Hope this helps.
Joined: Jun 2003
Posts: 206
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From: _
AirbusFan, out of curiosity could you please elaborate on the instances you've been told of where the system logic doesn't behave as expected? Is it a pilot/engineer that told you of these accounts? I'm just interested to hear how such an inherently simple piece of system logic can go wrong, it seems strange.
Thanks in advance
Thanks in advance




