Peter Gibbons said:
The Rules of the Game article "All About Movement (Part Four)" by Skip Williams points out that hovering is either a free action or move action. If you are rendered unconscious, you cannot take the action to hover, so you fall.
Using the Hover
feat requires taking a move action to cease forward motion.
If you begin your turn already hovering, no action is required to continue hovering using the feat.
Hovering via Good or Perfect maneuverability doesn't even have that restriction.
"It's a free action to hover" isn't supported by a quote from the rules.
So, if a gargoyle with the Hover feat is flying and is stunned, he stalls and falls.
If a gargoyle with the Hover feat is flying, takes a move action to begin hovering, and
then is stunned, strictly, he doesn't stall, since he's not required to maintain forward motion while hovering.
If a gargoyle with the Hover feat is flying, takes a move action to begin hovering, and then is Paralyzed, he falls, under the rules for winged creatures and paralysis.
If an arrowhawk is flying and is stunned, he stops moving. He has no minimum forward speed to avoid stalling, and his Perfect maneuverability allows him to hover. If he's Paralyzed, he falls, under the rules for winged creatures and paralysis.
If an air elemental is flying and is stunned or paralyzed, he stops moving. He has no minimum forward speed to avoid stalling, and his Perfect maneuverability allows him to hover.
-Hyp.