So you don't need to file if flying outside class A, but what about through class D? I've flown a couple routes mostly outside class A but have filed a flight plan all the same. Problem with that is that I've had to freecall every en route frequency, increasing workload except where the guys on the ground have provided a handover out of courtesy. Would it be sensible to file a flight plan with all the en route ATS units even when staying outside class A?
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