Isolated Aerodromes!
Hello, Gents!
I was wondering about EASAs definition of an isolated aerodrome. From one hand in CAT.OP.MPA.106 is written that:
An isolated aerodrome is one for which the alternate and final fuel reserve required to the nearest adequate destination alternate aerodrome is more than:
for aeroplanes with turbine engines, fuel to fly for two hours at normal cruise consumption above the destination aerodrome, including final reserve fuel.
But from the other hand in SOP.OP.105
For the selection of alternate aerodromes and the fuel policy, the operator shall consider an aerodrome as an isolated aerodrome if the flying time to the nearest adequate destination alternate
aerodrome is more than:
(b) for aeroplanes with turbine engines, 90 minutes.
How to understand this? Does this 90 min are a result of 2 hours above destination at cruise consumption minus 30 min of final reserve?