 How is Lane able to hover over the buildings?
Raging , Trooper Lane hovered three thousand feet above Tammany Square. The humming paragrav-paks embedded beneath his shoulder blades held him motionless above Newyork's three administrative towers. Two black paragrav-boats whirred along the translucent underside of Newyork's anti-missile force-shield, the Shell. Lane dropped lightly to the floor, inside the room, in battle-crouch. "Lashing police with his vibray," said the announcer, "Lane broke through the cordon surrounding Manhattan Armory. Citizens are cautioned to keep clear of him. The two police boats were hovering above the towers. The force-bomb "exploded"—swelled or inflated, really, but with the speed of a blast. It shaded the view from his window and re-entered the tower wall just below.
 He has anti-gravity devices implanted in his body.
 He has anti-gravity boots.  He is in a helicopter.  He has a jet pack.  He has anti-gravity devices implanted in his body.