wheels = x, treadmill = -x
plane doesn’t slow down, so wheels become 2x
wheels = 2x, treadmill = -2x
plane doesn’t slow down, so wheels become 4x
wheels = 4x, treadmill = -4x
plane doesn’t slow down, so wheels become -8x
wheels = 8x, treadmill = -8x
plane doesn’t slow down, so wheels become -16x