According to the C-17 "acquisition" documents just released (thanks Ngati), to meet NZ's portion of the Antarctic flight obligations, perhaps only required three C-17 flights a year. With a C-5M, maybe they would only need to prep it for one trip a season!
It doesn't seem that C-17 is going ahead (it appears even the 7-year lease option for one aircraft has been turned down), so we need to think about Plan B. I think we need to give a tanker option some serious thought. Probably a 767 derivative rather than an A330. A Multi-role Tanker Transport (MRTT) could offer the extra role & range that the 757 doesn't (hence the bad-mouthing it received in the 2010 Value-for-Money report). A 767-200ER could carry approx 200 passengers or 19 standard pallets to a deployment + maintain VIPs in the style that they have become accustomed, while being able to assist with tanking duties during Antarctic runs (eventually it might even be cleared to land at McMurdo itself). But we are talking close to C-17 money for such an aircraft. A second-hand conversion could be a good choice again.
If we acquire P-8, then a tanking option could very well come in to it's own, as the P-8 sucks (fuel, literally) at low-level. We have an absolutely huge SAR zone, and search-and-rescue missions (which involve lots of low-level flight) will be a major role for the Orion replacement capability.
I was extremely disappointed with the cabinet decision to go with a 'like for like' replacement air transport capability. Neither the C-130 or the 757 meets current or future needs. A complete cop-out! Despite the supposed $20 billion commitment, we will actually be spending less between now and 2018 than even the 2013 DMRR proposed. Too many morons at the top table seems to be the fundamental problem. They just need to start getting the 'bleepity-bleep' on with it! A heavy-lift squadron (be it 3-4 A400M or C-2, backed with 1-2 MRTT, for example) seems essential. Just too tight to pay for it and too deluded to admit that things are currently not in any way adequate.:frown