 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. It shaded the view from his window and re-entered the tower wall just below. The cannon trundled into the Square on its olive-drab, box-shaped caterpillar mounting and took up a position equidistant from the bases of the three towers. Lane's defense is a globe of energy similar to the one which protects Newyork from aerial attack."
 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.