What does "turning into a tailwind" mean?
If the wind is a constant velocity an aircraft in the air never turns into a tailwind. The wind will affect the aircraft's groundspeed and track depending on which way the aircraft is heading, but the aircraft's TAS is not affected by the wind.
Now if it's a 300 kt northerly at 200' and a 300 kt southerly at 100', the aircraft will be destroyed on descent...