Is it not the case that at, say, 5NM above the Earth's surface travelling at 500kts, in order to follow a trajectory parallel to the Earth's surface (let's assume it to be sperical) it will be necessary to follow a trajectory which will result in a load factor very slightly less than 1g?
Obviously there is middle ground between the orbiting satellite (0g) and the stationary object at the surface (1g); maybe a cruising airliner is in a regime where the effect is measurable?
I confess to being too lazy and dim to do the sums but it may be the case that a nominal "1g" trajectory at FL350 would result in a slight barometric climb?
As an aside, the conc flies with about 1degree of bank in the cruise due coriolis effect, so these things are measurable.
Sorry - no answers just questions, any clever b*gg**s out there?