This means that a plane will fly a longer or shorter distance than that on the actual earth? Flight times on east-west flights will therefore be very different to those west-east between the same points. eg. New York-Paris.
inquisitive, again, do you want to discuss the "real world" with probably a dozen factors - all at the same time - to see the effect? This WILL be difficult to do because each factor can influence the flight at different times during the flight and can appear or disappear or change in magnitude (e.g. wind).
In your question above, YES, the distance (flight path) will change on the actual earth as will flight times. The
ground distance does not change but flight path and time do.
For example, where is the Jet Stream at the time the plane is flying? How does that affect weather/wind velocities (flying with a tail wind vs head wind)? When are you taking this flight? - as the Jet Stream changes over time. How does that affect flight time/path (sometimes airlines will fly planes differently (different paths) to avoid those head winds or get into tail winds)?
Does a flight from NY-Paris sometimes go around weather in the North Atlantic? How does that affect flight time/path?
Are we talking about the Concord, a 747, Lear Jet, or F16? Their flight characteristics vary. The other factors will probably affect one type of plane more or less than another. How does that affect flight time/path?
This is why airlines give you an estimate on flight time - but the actual fight time can vary - sometimes by a lot (even something as stupid as planes being "grounded" - that would change the flight time from NY-Paris, perhaps by a day or two).
Either we discuss the "real" world with its dozen factors at the same time or we don't. You can't just pick some and ignore others.
We CAN discuss one factor, isolating it from the others, to see how it affects the trip (i.e. the Coriolis Effect I was discussing). Adding other factors simply makes the Coriolis Effect more confusing than it already is.
Finally, this discussion here is why we discuss the Coriolis Effect with bullets instead of planes. Planes complicate discussions A LOT - needlessly. Half of the factors would not make any affect on a bullets traveling a few seconds over a few kilometers. To be sure, the factors exist but are negligible. The discussion would be greatly simplified.