The a/c is at 1g while cruising and it is the gravity that stops it shooting off into space, not "pushing to follow the curve"?
Yes and no. The centrifugal force that arises from trying to stay still in a rotating frame, or alternatively the force required to provide the acceleration to make the thing go in a circle rather than a straight line, is a real effect.
The good news is that the force appropriate to hovering over a particular lat-lon position is conventionally incorporated into g, the acceleration of free fall, in addition to gravity. The bad news is that if the object in question is moving with respect to the earth, we're faced with
coriolis force as well...
But our torturer in this case specifically excused us from thinking about earth rotation or aircraft speed.
(My money's on the pound of feathers, BTW
)