Freefall has the ability to manipulate gravity to various effects.
We can't manipulate gravity as a field; we don't even have a set of equations for it that we can agree upon.
"Maybe they have some way to manipulate gravity and inertia locally."
He also has the ability to manipulate gravity by rotating his face.
Let's assume they can manipulate gravity to some extent.
(Note that many giant-sized characters have a limited ability to manipulate gravity to handle their increased weight.)
Another unit came down, one that would allow the flux generators to manipulate gravity and inertia so as to produce flight.
Rory has the ability to manipulate gravity.
Both manipulated gravity and light; the second pair was stronger than the first.
By manipulating gravity, he was able to fly.