An engagement structure adapted for securement to the end of an aircraft boarding bridge includes a floor, a first floor panel rotatably associated with the floor, and a second floor panel displaceably associated with the floor. The second floor panel is preferably mechanically associated with a drive assembly adapted for displacing the second floor panel relative to the first floor panel to provide a dimensionally adjustable floor area of a boarding bridge proximate the interface of the bridge and an aircraft serviced by the bridge. The engagement structure is adapted to accommodate the docking of the boarding bridge with aircraft having varied entry door configurations.