TiiberiusKirk
KTAS (True Air Speed), i.e. the speed the aircraft is actually travelling through an air mass, has nothing in common with the GS (Ground Speed). Consider an aircraft with 250 KTAS and a tail wind of 100 KTS. It will have a GS of 350KTS, and likewise 150KTS if it was pushing a 100KT head wind.
The aircraft performs relative to the airmass which it is in.
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