The floating waypoint
Greybeard: see #389 & #392. If you look at the sequence of the four different waypoints in #392, the change you are referring to is from (2) to (3). But the nav officer who made the change thought the waypoint was (1) – hence the one digit error.
I suppose you can’t blame old Mahon for getting a little bit tired of hearing about all these errors, but I can’t see how anyone can say that the McMurdo Sound waypoint was anything other than an error. In other words, the nav track was supposed to go over the active volcano to the NDB, and that’s where all the AirNZ witnesses thought it went.