.. hey everyone.... a question I have asks me the legal minimum fuel to be on board at engine start for a single piston engine vfr charter operation... and there has been 2 litres for final taxi at destination included in the details .... is this a legal requirement?

A quick read of CAAP 234-1(2.1) tells the story as CASA would have it -

(a) taxi fuel is defined only for the departure aerodrome, ie we are not interested in taxi at the destination/alternate

(b) emergency fuel defines the minimum quantity with which you are expected to land (fixed reserve)

(c) fuel at the commencement of flight makes no reference to final taxi fuel (nor is it defined in the CAAP, anyway)

In essence, you are perfectly entitled to use a bit of the fixed reserve to look after the final taxi if your gameplan doesn't foresee your landing with some additional margin. Indeed, should you wish to do so, there is nothing to stop your taxying around at the destination until you run out of fuel.

People might look at you a tad strangely but that's OK, you can just shrug your shoulders and ignore them.

The final taxi fuel quantity quoted is only there to try and confuse folks.

Thanks John...another fuel question... say my alternate airport weather report shows a inter....
So far, my actual destination airport is good weather wise... I just have to have 15 mins of fuel for traffic... do I just rely on the fixed reserve I have calculated for my trip to my destination ? I don’t then bring along another 30 mins of fuel due to the inter... as this inter is at my destination alternate....?

As I read your question, you are concerned with an in-flight replanning situation ?

In this case you need to be compliant with, at the least, 4.3.1 or 4.3.2, as appropriate. That is to say, at all times you want to make sure that you have enough fuel to keep you out of mischief for the remainder of the flight. We would need more in the way of specific details for the example to come up with a more specific answer.

You can't, for instance, use the fixed reserve to cover for the destination OPR as you still need to have both fuel quantities available when you get to the alternate.

So, at planning, and any point in flight, you always have to have enough fuel on board to cover the relevant fuel requirements for whatever your gameplan may be at the time. The only way you can shave the fuel at departure is by doing some sums to establish that you should be able to replan in flight to use such variable reserve as you may have saved along the way to provide for the alternate OPR. This is not at all uncommon practice on larger aircraft.

If you get to the stage where there is a real risk of going into your fixed reserve prior to landing, then it's a fuel emergency declaration to take advantage of whatever priority handling may be available to you in the circumstances. Above all, don't knowingly put yourself in a situation where you are/could be faced with a real possibility of running really low, or out of, fuel. You just don't need that sort of excitement in your day, I suggest.