Re: flying north
Flywatcher, give us a bit more info and i will try and help you out. PM me if you like.
How long have you got, what sort of budget. What are your main interests, tourist attractions like Ayres Rock Katherine Gorge and Cairns or a little more adventurous. Fishing, cattle station, or an interest in visiting aboriginal communities?
Wouldn't worry too much about water etc until you have a more definite plan. If you intend following major highways, have HF and only landing at reasonable size airports then lots of water will not be quite as important as if you fly Birdsville direct to Alice etc.
With a C182, you will have good range, you should not have too many problems getting fuel at some of the larger airports and won't need pumps and fuel transported in for you, but again wait until you have a better idea of where you are going.
whilst a sat phone would certainly be handy, (I have been flying around the NT and QLD for 20+ years and never had one) it certainly is not essential. Like wise with HF. If you have one great, if you don't then you may consider your route.
You will find the centre still gets pretty hot that time of year and therefore turbulence. Mornings are best, better vis, cooler and turbulence less likely.
Anyway drop a pm and I will try and help you out