Jet bridge
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.
History
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 “Aero-Gangplank”, as it was dubbed by inventor Lockheed Air Terminal, was installed by United at Chicago’s O’Hare Airport in 1958.
Designs and use
In the simple case, there is only one passenger bridge that docks at the front entrance of the aircraft. But there are also passenger buildings, on which two boarding bridges lead both to the front and / or middle and to the rear entrance. The number of passenger boarding bridges leading to the aircraft depends on the number of seats. In order to keep the service life as short as possible, the aircraft should be loaded and unloaded as quickly as possible. For the Airbus A380, there is also the possibility to dock with a third finger on the upper deck at some airports.
The bridge is operated by an airport employee, the so-called bridge driver, who docks with a joystick and often electronic help to the door of the aircraft. Most bridges are three-dimensionally movable mounted on a rotatable and adjustable in height suspension. They can thus be adjusted in height, laterally and in length to suit the different aircraft types.
However, there are also boarding bridges, which are only height and length adjustable. For each type of aircraft, there is a separate marking on the apron, where the nose wheel must hold. Once the aircraft is stationary, the fixed passenger bridge only needs to be moved up to the fuselage and nestle against the aircraft skin. This type of passenger boarding bridges used to save the more expensive, three-dimensionally movable passenger bridge structures. Passenger bridges of this type are, inter alia, at the airports Berlin-Tegel (Gate A3 to A12), Helsinki-Vantaa and Kuching in operation.
The passenger bridge has a padded bead at the front bottom, with which it conforms to the aircraft skin, and as a roof, a movable bellows, which is closed at the top after docking and thus provides a weatherproof access. As the aircraft moves up and down during loading and unloading due to the shifting of the load or the passengers, passenger boarding bridges are equipped with a height sensor and automatically adapt to the changed height.
Parking positions with passenger boarding bridges are located directly on the building, so the aircraft is parked with the bow to the building in the so-called Bay (nose-in). It then has to be pushed back to the departure with an aircraft tractor (pushback). There are also airport buildings where the planes are parallel to the terminal. The passenger boarding bridges must be longer accordingly. Some piers are also designed so that aircraft park obliquely forward at the terminal building (angled nose-in). After boarding the passenger boarding bridge, the aircraft then makes a tight forward turn to move away from the terminal building. This eliminates the need for an aircraft tractor and saves time. Disadvantage of these two forms of parking positions is the much higher space requirement. Airports using this form of passenger boarding bridge are Paris-Charles-de-Gaulle Airport (Terminal 1) and Cologne-Bonn Airport (Terminal 1).
Advantages
Jet bridges provide all-weather dry access to aircraft and enhance the security of terminal operations. They are often permanently attached at one end by a pivot (or rotunda) to the terminal building and have the ability to swing left or right. The cabin, at the end of the loading bridge, may be raised or lowered, extended or retracted, and may pivot, to accommodate aircraft of different sizes. These motions are controlled by an operator’s station in the cab. The cab is provided with an accordion-like canopy, which allows the bridge to dock with aircraft with differing shapes, and provide a nearly weather-proof seal. Additionally, many models offer leveling devices for the portion of the floor that makes contact with the aircraft; this allows passengers to slowly transition from level aircraft floor to sloping jet bridge floor. As such, jet bridges provide enhanced access to aircraft for passengers with many types of disabilities and mobility impairments, as they may board and disembark without climbing stairs or using a specialized wheelchair lift.
Some airports with international gates have two or three bridges for larger aircraft with multiple entrances. In theory, this allows for faster disembarking of larger aircraft, though it is quite common, especially on aircraft such as Boeing 747s and Boeing 777s, to use one bridge for only passengers in first class and/or business class, while the other bridge is for the use of passengers in economy class. The Airbus A380 is unique in that both of its double decks have outside doors; so that two or more loading bridges are possible, a jetbridge for each deck having the advantage being faster aircraft loading (in parallel). Such connectors are being constructed at Boston’s Logan Airport, Kuala Lumpur International Airport, Hartsfield-Jackson Atlanta International Airport, Johannesburg International Airport and in the new international terminal at Calgary International Airport. Faster loading can lead to lower airport charges, less delays and more passenger throughput for the airport, all factors which impact an airline’s bottom line.
Though loading bridges are usually permanently attached at their terminal-building end, leaving only the cab free to move, this is not always the case. Those at Melbourne Airport’s international terminal are — and at Hong Kong’s old Kai Tak Airport were — anchored in the middle and movable at either end to permit the terminal building-end to be raised or lowered to connect with either the departures level or the arrivals level of the terminal building.
They allow quick and easy access even in adverse weather conditions, as well as providing security to airport operations.
The boarding bridge is permanently connected at one of its ends by means of a pivot to the terminal and can be moved to the sides, up and down, in addition to being extended or retracted; at the other end it has a bellows that allows it to adapt to the different dimensions and shapes of aircraft. These movements are controlled by an operating station at the end that faces the aircraft.
Boarding gates with boarding bridges usually have a series of lines painted on the ramp, to assist during parking maneuvers of different types of aircraft. An appropriate position facilitates the task of the boarding bridge operator, since it allows to correctly attach it to the fuselage.
Some airports such as Schiphol Airport in Amsterdam, that of Charles de Gaulle and Inchon International Airport in Seoul, have two boarding bridges for aircraft larger. This allows, in theory, a faster boarding / disembarking for this type of aircraft ; however, it is very common to use one for passengers in first class and business class, while the other is used for passengers in economy class. With the arrival of the two-floor Airbus A380, it is anticipated that each floor will have one or more boarding bridges. This kind of bridges are being built in theChangi Airport in Singapore in preparation for receiving the first Airbus A380 to carry out commercial flights.
Disadvantages
Loading bridges restrict aircraft parking to spots immediately adjacent to the terminal. Thus, airports use mobile staircases to facilitate disembarking at hardstands (remote parking positions).
Loading bridges may pose hazards to aircraft if handled improperly. If the bridge is not retracted fully before departure, it may contact protruding parts of the taxiing aircraft (e.g., a pitot tube), requiring repair and delays. Furthermore, during cold weather, the loading bridge may become frozen to the aircraft. In this case, when the jet bridge retracts, it could damage the aircraft if that area has not been properly de-iced.
When regional jets are used, jet bridges have another disadvantage, since they allow only one aircraft to park at the gate at a time. Several airlines have removed jet bridges at regional jet gates at airports such as Atlanta which are short on gates. When having passengers disembark on the tarmac or the ramp, airlines can fit two or more regional jets per gate. In many other places like Beijing Capital Airport and Paris Charles de Gaulle Airport, a gate for large aircraft can be used to accommodate two smaller aircraft like Boeing 737s or Airbus A320s.
Several incidents of jet bridges collapsing include Sydney, Hong Kong, Seattle and Los Angeles.
The installation of teletrap is associated with significant material costs and specific requirements for the architecture of the terminal, which are justified for a significant passenger flow.
The use of teletrap is possible only if the aircraft is installed directly next to the terminal, thereby limiting the number of such parking spaces. Most airports in the world therefore continue to use mobile ladders in remote parking areas and the transport of passengers on special airfield buses.
The aircraft located at the terminal, as a rule, can not taxi itself out of the parking lot: it is necessary to tow the aircraft with towing vehicles to a special site, indicated by the flight director, where the engines are started and the liner starts to steer forward. All this requires additional time and availability of special equipment and personnel.
Towing the aircraft in reverse from the terminal building and, of course, from the tether, requires certain financial costs of the airlines, so many of them in advance specifically agree with the airport management on setting up the company’s long-distance aircraft: a common self-propelled gangway and a conventional airbus stand for the airline much cheaper than towing a liner by tractors using expensive fuel and charging from the carrier’s company for servicing its flights through a telescopic rap.
In the winter, the airborne vehicle may freeze and damage the aircraft if the docking location has not been adequately treated with anti-icing agents
Use at small airports
Jet bridges are occasionally used at smaller, single-story airports. This is accomplished by a flight of stairs and, in some instances, a wheelchair lift. In this scenario, a passenger proceeds through the gate and then up a flight of stairs to meet the height of the jet bridge. An example of this can be found at South Bend International Airport in South Bend, Indiana. Alternatively, a ramp can be used in the terminal building to bring the passengers from the waiting area to the height of the jet bridge. For example, Sawyer International Airport, located near Marquette, Michigan in Michigan’s Upper Peninsula, has jet bridges that can load passengers onto smaller passenger aircraft such as the Saab 340 turboprop. The Ithaca Tompkins Regional Airport at Ithaca, New York has two gates using this approach. This can be done to attract larger airlines that require use of a jet bridge to the airport, as well as to make disembarking smaller planes easier for disabled people and to improve the disembarking process in bad weather.
Use and appearance
At the airport terminal, the bridge is connected to a portal (called a “gate”) in the terminal wall behind the gate desk. Once airplane boarding starts, passengers hand their boarding passes to the gate’s attendant, who lets them pass through.
Inside, the bridge looks like a narrow, lighted hallway in an office building, without doors. Loading bridges usually have no windows, but glass walls are becoming more common. The walls are normally painted in accordance with airline standards, generally with relaxing colours. Some bridges have advertisements on interior or exterior walls. The floor is generally uneven with many bumps, creating a hazard for wheelchairs and individuals with mobility issues.
By using a retractable tunnel design, loading bridges may retract and extend varying lengths. Some airports use fixed walkways to effectively extend the reach of a loading bridge. The fixed walkway extends out from the terminal building and connects to the loading bridge rotunda. Occasionally, fixed bridges lead to multiple loading bridges. There are some jetways (such as several older bridges on the north terminal at Edmonton International Airport) that sit directly on the ground, as opposed to supports. These jetways are often used by small airlines or airplanes that are sometimes too low for conventional jetways (such as the Dash 8 and CRJ).
The cab of the loading bridge is raised and lowered to dock with aircraft of differing sill heights. The height of the cab is matched to the height of the aircraft door sill height. This often results in a slope along the length of the loading bridge.
Controls in older systems contain a large number of individual motor control buttons, with efficient operation requiring a high degree of operator skill and experience. Modern control consoles are much simpler, with only a few buttons, a graphic display console, and a single multi-axis joystick, with an overall appearance similar to that of a video game console in a video arcade.
Additional Equipment
Passenger boarding bridges form the second point of the airport facilities. Therefore, they are also used to house technical auxiliary systems:
At some airports, the aircraft cabin is air conditioned via the passenger boarding bridge. Thus, the aircraft’s APU can remain idle while parked at the gate, reducing noise and environmental impact.
Air ducts are used to defrost the aircraft (engines and chassis) in winter or for air conditioning in summer.
Supplying the aircraft with ground power without the use of a mobile ground power unit.
Telephone lines were sometimes provided prior to the proliferation of mobile phones.
A staircase allows the ground staff quick access to the machine, z. B. Tanker drivers (to let pilots acknowledge the acquired fuel) or baggage handlers (to pick up prams or mobile walkers from passengers).
Some passenger boarding bridges have an inclined lift, which is mounted parallel to the stairs, for example to be able to create magazines faster from the apron into the aircraft.
Garbage bags are drained via garbage chutes and can be picked up by garbage trucks on the airfield.
Many airlines provide newspapers / magazines. For practical reasons (delivery together with the newspaper shops in the airport) these are usually stored in the head of the passenger boarding bridges and there distributed to the passengers.
Marketing
Marketing space on jetways was uncommon until the early 2000s when HSBC launched their campaign “The World’s Local Bank.:
Peter Stringham, head of marketing for HSBC worldwide, worked closely with Lowe’s, the Group’s global agency, in developing the campaign which required a single global platform. Stringham noticed jetways were a global medium which had not been tapped.
HSBC thus bought the rights to jetways across major localities in 81 countries and territories. Hence, the vast majority of advertising on jetways globally display HSBC advertising.
Procedure
The procedure for using passenger boarding bridges is regulated by national regulations and internationally standardized procedures. A typical procedure is:
After the signal from the instructor to the pilot to shut off the engines, the instructor releases the passenger boarding bridge by a show of hands.
Only now is the driver allowed to leave the secured area with the passenger boarding bridge and dock.
By knocking against the porthole, the driver signals to the crew that the bridge is safely docked and the door may be opened. This is to prevent people from being forced out of the passengers by pushing the door open prematurely and fall into the gap between the aircraft and the passenger boarding bridge.
The driver signals security personnel at the gate to open the doors for incoming passengers (in person, by telephone or via a buzzer).
The passenger bridge is now only for leaving the machine.
After boarding the passengers, the bridge can be used in both directions (eg to change the crew).
After the crew announces readiness for boarding, the doors are opened at the gate for departing passengers.
After boarding, the crew confirms the readiness to take off.
The driver secures the door of the bridge (chain, door or roller shutter) and drives the passenger boarding bridge back into the secured area. Only after it has been released may the instructor allow the machine to move.
Source from Wikipedia