you forgot to mention that the descent from 16,000 to the minimum of 6,000 had to be in VMC. So what were the stipulated VMC limits? There is nothing in the report that I can find, though the regs in force at the time state 8Km vis, 1 mile horizontally & 1,000 feet vertically.
I have not found any specially laid down VMC requirements for that portion of the approved descent. However, as it was a requirement to be under radar monitoring and in the laid down area that was well clear of Mt Erebus I would think in unlikely that anyone ever got round to producing special VMC requirements just for that portion, 16,000ft to 6,000ft.
The question is not really relevant though, the weather at McMurdo was well below that required for the only approved descent below MSA.
3 Holer,
..................and the ONLY reason a mountain was in the way was because some one changed the final co-ordinates of the route without telling the crew
Have you any idea what requesting and getting a VMC descent entails? You take on responsibility for your own terrain and traffic avoidance. As has been shown in this thread many times, changing the waypoint was sloppy operating but was not the cause of the disaster.