So, HMAS Success - a Durance Class replenishment oiler - is said to have a range of 8616 nautical miles at 15 knots and can offload 8707 tonnes of diesel. Does this mean she could travel 4308 nautical miles, offload all that fuel and travel back? (Roughly speaking.) Or is the fuel she carries usually inclusive of her own needs? Similarly, could she draw down on some of her cargo fuel to travel further? Does anyone have any idea how much fuel she carries in her own bunkers?
Basically, what I'm wondering about is the requirements for a naval task force to travel a great distance and back without need of stopping in a port.
I'm also curious about how fuel has changed through the years. The diesel ships commonly use today wouldn't be the same as that used during World War 2, for example, would it? If a modern ship was somehow back to that era (Twilight Zone), could a suitable fuel be refined for her using the technology of the day?
Also, ships that run on Combined Diesel Or Gas - do refuellers commonly carry gas at sea?