VSD
can you explain how the runway can be above or below the ground if both terrain and the approach slope/runway are all tied to a common barometric altitude?
as far as I can tell, no radio altimeter inputs are used for the VSD.
The power point training referred to earlier in this thread does not discuss what the VSD presentation will do with an incorrect QNH setting when flying a non ILS type approach.
Any technical explanation on this would be appreciated.