Jet bridges

A jet bridge (also termed jetway,gangway, aerobridge/airbridge, air jetty, portal, skybridge or its official industry name passenger boarding bridge (PBB)) is an enclosed, movable connector which most commonly extends from an airport terminal gate to an airplane, and in some instances from a port to a boat or ship, allowing passengers to board and disembark without going outside or being exposed to the elements. Depending on building design, sill heights, fueling positions, and operational requirements, a jet bridge may be fixed or movable, swinging radially and/or extending in length. The jetway was invented by Frank Der Yuen.

Before the introduction of jet bridges, passengers normally boarded an aircraft by walking along the ground-level ramp and climbing a set of movable stairs, or up airstairs on aircraft so equipped. Mobile staircases or "ramp stairs" are employed at many airports around the world, particularly smaller airports and terminals supporting low cost carriers.

United Airlines tested an early prototype "Air Dock" in 1954. The first operational jet bridges were installed in 1959, although sources disagree as to which airport installed jet bridges first. Some accounts state that the first jet bridge was installed on July 22, 1959 at Hartsfield–Jackson Atlanta International Airport; other accounts place the first jet bridge at Chicago O'Hare International Airport, Los Angeles International Airport, LaGuardia Airport or San Francisco International Airport.

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