When flying at FL290 at mach 0.89 with a tailwind of about 100 knots, would the speed stand also at...........

Question

....... mach 0.89 when the tailwind suddenly would decrease to 0, or even change suddenly to a headwind?

Answer 1

Hundred knots to zero? Uh uh. Ain't happenin.

Answer 2

If a 100kt tailwind _suddenly_ went away (for example, flying into a windshear situation), the airspeed would suddenly increase by 100 knots, the plane would pitch up rather abruptly, and then the airspeed would bleed back down to what it was before.

The ground speed on the other hand wouldn't change at the instant that the tailwind went away, but would decrease as the airspeed readjusted itself.

Answer 3

The indicated airspeed, the true airspeed and the mach number would increase momentarily, then decrease back to mach .89  The groundspeed would eventually decrease by 100 knots.

Answer 4

What speed? Airspeed? Groundspeed?

Airspeed would be constant.

Groundspeed changes with the headwind/tailwind.