Abstract: An apparatus that raises and lowers a rotatable vestibule of the type used in airports to transfer passengers from a terminal building to a passenger loading bridge. A first plurality of telescoping columns are interconnected to and passively follow a second plurality of telescoping columns disposed interiorly of and in concentric relation with said first plurality of columns when the second columns are activated. J-shaped bushings made of Nylitron facilitate the extension and retraction of the columns and flat sections of that material provide additional bearing surfaces at other locations of the apparatus. The J-shaped bushing also provides stops that limit the extension of the apparatus.

Abstract: An improved system for facilitating the movement of passengers at a transit terminal comprising a terminal building having a plurality of passenger transfer zones disposed one above the other. Each transfer zone may include a platform with a recessed area at the edge of the building, an airplane positionable at a distance from the building which has a door with a threshold across which passengers may move and an elongated walkway which has a first end and a second end. Positionable with its first end adjacent to the airplane with its second end positionable adjacent to a preselected one of the transfer zones. Each end has a supporting structure therebetween for retaining the supported end at one of a plurality of elevational positions whereby the first end may be placed at a height corresponding to the threshold of the airplane independent of the height of such threshold and the second end may be placed at a height corresponding to one of the transfer zones.