Battering Blast vs. Flying Targets

[fuzzyillogic]

It is stated in the rules that you can't trip some kind of creatures, like the flying ones.

On the other hand, in the Battering Blast spell description, it does not say that it does trip, it says that if the Bull Rush attempt have been successful the creature must attempt a Reflex save or fall prone, a specific addition to the Bull Rush rules.

battering blast:

A creature struck by any of these is subject to a bull rush attempt. The force has a Strength modifier equal to your Intelligence, Wisdom, or Charisma modifier (whichever is highest). The CMB for the force’s bull rush uses your caster level as its base attack bonus, adding the force’s Strength modifier and a +10 bonus for each additional blast directed against the same target. Each sphere of force makes its own separate bull rush attempt—if multiple spheres strike one target, you make multiple CMB checks but only take the highest result to determine success. If the bull rush succeeds, the force pushes the creature away from you in a straight line, and the creature must make a Reflex save or fall prone.

What does this mean for a flying target? Does the target fall to the ground to be rendered prone? taking maybe falling damage too?

For a winged or similar target it does make sense, but what about floating targets?

Also, if the target does effectively fall to the ground anfter having been batttered, his altitude should be adjusted by his movement away from the caster: as a limit case, if the caster was directly under the target when he hurled the spell, the target should be bullrushed straight up 5+ feets, and then fall down all the distance to the ground, at the very feet of the caster himself.

Technically we could even discuss about the other creatures that are immune to trip, like oozes and creatures without legs, but I guess that that would be a bit of difficult to justify with common sense.

I know how I would resolve most of these things, but I'm curious to know if there're official rules/rulings that I've missed and what other players/GM thinks...

[fizzel]

I guess by RAW it would be so. If the target does fail the saving throw, is knocked prone even if flying, or without legs or anything.

Now, the consequences of the flying target getting knocked prone I don't know, I guess I would have a floating flyer use the "avoid falling damage" section of the fly skill, while I would resolve a winged flyer according to the "collision while flying" section of the same skill, but that's my interpretation...