Originally Posted by
Uplinker
I wonder if the above is adequately explained to pilots; i.e. if disturbed, the aircraft will not regain the original "glide-slope" but will parallel it, either above or below.
You’d be surprised.... few people realize.
FPA as a flight guidance target is a performance target, not a geometric target. As you said.....
Off-topic
PS: hence the preference to use ALT p/b iso Push to Level Off in the A330 for EFATO-3rd segment and Circling. ALT is a geometric mode, well barometric really (locked to an ALT) whilst PTLO merely targets vs=0, prone to disturbances: parallel tracking.