ANI was absorbed by Antarctic Logistics Expeditions a couple of years ago.
I don't believe that they own any aircraft - instead they charter in Kenn Borek's Twotters, and the Russians' IL76.
ANI used to charter in SAFAIR's C130, but I don't think they do that any more (IL76s are cheaper I guess!).
If you have to fly in Antarctica (and I thoroughly recommend it
) other operators down there for fixed wing ski work:
- Enterprise Air BT67 Basler working for the Russians between Molodeznhaya, Progress and Vostok
- AWI (German) DO228s also flying around ex Molodez. and around Dronning Maud Land
- Australian CASA212's between Casey, Davis, Mawson and other places.
- BAS twotters (with a DHC7 flying to/from Rothera)
- Kenn Borek's DHC6's all over the place
- Various military stuff (US, NZ, Italian) from CHCH to McMurdo to SPole (but I expect you'd know about thier movements from NZ). Some ski, most wheels.
- Russian IL76's from Capetown to Molod (also Troll's blue ice runway), also from Puntas to Patriot Hills. These are wheeled operations to Blue Ice.
Good luck!