Originally Posted by
FlyingStone
It just depends on the environment you operate in. Mind you that when this book was published, they didn't have any of thte RNP AR and alike and I bet London and New York TMA were slightly less busy.
The aircraft I fly has a demonstrated RNP ability of 0.64nm for raw data using MAP display at 10nm range. You can't even handfly a normal RNAV approach like this.
It is not only environment, but also aircraft. I flew the 737 with IAN enabled and with that it is easy enough to hand fly an RNP approach. It was approved and encouraged in the company i flew for and i did it a lot. On the bus it is theoretically possible, but not really pleasant at all and nor encouraged, and depending on operator, not approved, haven't flown the IAN look-a-like FLS, as that is not standard equipment on the A320 series.
This case and report is somewhat puzzling, and yes it sounds like FD fixation without realising where they were (aviate, yes, navigate, no). Dunno, for me the vertical situation display was always a great help on the 737, but apparently that is not standard either.