Fredairstair,
to start with the final reserve is: For aeroplanes with turbine power units, fuel to fly for 30 minutes at holding speed at 1 500 ft (450 m) above aerodrome elevation in standard conditions, calculated with the estimated mass on arrival at the alternate or the destination, when no alternate is required.
So one can say it's equates to a holding fuel and to determine the amount one can refer to VOL 2 on the BUS.
An operator can prescribe a compulsory min amount of fuel upon touch down being more restrictive than JAR. Usually it's a recommended fuel upon landing.
If one takes flight plan fuel one can use any amount of fuel he/she deems necessary anywhere during the diversion to an en route alternate or at destination or the destination's alternate until the commander reaches the final reserve plus fuel required for the approach. Let's say it'd be 5 tonnes for an A346 Having hat amount of fuel physically on board a PAN call is due with fuel remaining in minutes. Having the final reserve 3.7 t for A346 physically on board a MAY DAY call is due.
In regards to in flight fuel management
In-flight fuel management.
(1) If, as a result of an in-flight fuel check, the expected fuel remaining on arrival at the destination is less than the required alternate fuel plus final reserve fuel, the commander must take into account the traffic and the operational conditions prevailing at the destination aerodrome, along the diversion route to an alternate aerodrome and at the destination alternate aerodrome, when deciding whether to proceed to the destination aerodrome or to divert, so as to land with not less than final reserve fuel.
It must be emphasized once again
REGARDLESS of where one lands JAR requires one to have only final reserve upon touch down nothing more or less. One can go below it provided emergency has been declared.
Cheers.
