What is a jet bridge?

The device goes by several names depending on who is talking. Airports call it a passenger boarding bridge, airlines often say jetway, and Jetway is in fact a brand name that became a generic term in the same way as Hoover. The first ones appeared in the late 1950s, and before that everybody walked down stairs onto the tarmac in whatever weather was waiting.

Each bridge has a cab at the aircraft end that rotates and a canopy that seals against the fuselage. An operator drives it into position within centimetres of the door, because the seal has to be tight enough to keep out rain and cold while the aircraft is loaded. That positioning is also why boarding sometimes starts several minutes later than the screens promised.

Not every stand has one. Remote stands need buses and airstairs, which is why a flight can be at the gate on the departure board while passengers are still being driven across the airfield. Smaller regional aircraft frequently board this way even at large airports, because the door sill sits too low for the bridge to reach comfortably.

For premium cabins the practical detail is the second bridge. Widebody aircraft at major hubs often use two, one at door one for business and first and another further back for the rest of the cabin. That is the reason priority boarding actually saves time on some aircraft and none at all on others.