What ground equipment facilitates boarding of passengers

Aviation Learnings

Learn How Airports Work

A Guide to Airport Ramp Operations, Ground Handling & Ground Support Equipment (GSE)

By Aviation Learnings Team

An airplane does not rest. It keeps flying from destination to destination. As soon as an aircraft lands and reaches airport gate, airline staff and ground handling agencies get busy with preparing the aircraft for departure.

Airport ramp operations, ground handling and ground support equipment are terms associated with the set of operations and activities that take place in supporting an aircraft on ground and preparing it for its next flight. We will explore these operations in detail today.

What we’ll cover in this article

Common Terminologies

Before we look deeper into what airport ramp operations are and how are they undertaken with the help of aircraft ground support equipment, you should be familiar with the terminologies commonly used in industry.

Ground Handling

The term ‘Ground Handling’ refers to the set of activities performed at an airport to facilitate the aircraft that has landed but hasn’t taken off. Hence the name ‘Ground’ handling i.e. handling an aircraft on ground as opposed to flying.

These activities include everything from ramp operations to baggage handling and extends to tasks that fall under airport management.

Ramp & Ramp Operations

When an aircraft lands on the runway, it finally reaches a place commonly referred to as an airport gate where passengers deplane the aircraft. ‘Gate’ is a term that relates more to the interface between an aircraft and airport building i.e. a passenger boarding bridge or lounge gate mentioned on boarding pass of passengers. The area where the aircraft is parked is called an aircraft stand, aircraft bay or ramp.

The term ‘ramp’ has come from maritime industry where the term ‘boat ramp’ has been used for the inclined wooden ramp on seashore used for parking a boat. There is no inclination at an aircraft stand therefore ramp is technically a misnomer, however, it is a term common in industry.

Consequently, all activities involved in servicing an on-ground aircraft and preparing it for departure while the aircraft is parked at the ramp are referred to as ‘ramp operations’ instead of being called aircraft stand operations or aircraft bay operations.

Ground handling is a broad term while ramp operations is a daughter term that covers only on-ramp activities and not off-ramp activities such as baggage loading and unloading on conveyor belts (located away from ramp).

Ground Support Equipment (GSE)

Ground Support Equipment (GSE) refers to specialized machines used for performing different servicing and support activities for the aircraft on ground. These machines are operated by properly trained personnel following standard procedures for carrying out the job with safety.

Airport ramp becomes a very busy place as soon as an aircraft is parked. There is a lot of movement of personnel and GSE all around the aircraft accessing different ground service connections of the aircraft to complete servicing tasks in shortest possible time to make the aircraft ready for the departure.

How Ground Handling Works

Ground handling operations and activities start before the arrival of the aircraft at the airport. The first task in ground handling is assignment of airport gate to an arriving aircraft. It is a decision made by air traffic control of the airport.

Assignment of airport gate is an apron management activity that also comes under the umbrella of airport management as a whole. It includes allocating different gates to different arriving aircrafts after an assessment of already occupied gates and type of arriving aircraft.

As soon as an aircraft lands, air traffic control informs the Pilot of the allocated gate as well as the route to be taken to reach that gate.

Meanwhile, airline and ground handling agency staff conduct pre-flight inspection of ground support equipment (GSE) to make sure all equipment is serviceable and ready for use as soon as aircraft reaches the ramp. All equipment parked elsewhere is towed to the ramp to avoid any delays.

How Ramp Operations Work

Ramp operations begin as soon as the aircraft approaches the ramp. There are more than 10 different ramp operations as given below,

Aircraft Marshalling

When the aircraft approaches the aircraft stand (ramp), another important ground handling activity known as aircraft marshalling is performed. It is the first ramp operation.

Aircraft marshalling refers to guiding the aircraft on the ramp with standardized hand signals by a specially trained ground staff known as aircraft marshaller.

Marshaller signals the pilot to keep coming forward, turn left, turn right and stop. These hand signals are standardized around the world to keep all pilots and ground staff on the same page and ensure that same hand signals convey the same message to the pilot irrespective of the destination.

Why Aircraft Marshalling is Needed?

The need for aircraft marshalling arises because an aircraft cannot be parked anywhere on the ramp and pilots cannot properly park the aircraft on a ramp on their own.

Every ramp has a centerline painted on ground with the aim of keeping the aircraft nose wheel over it to properly orient and center the aircraft on the aircraft stand.

Moreover, there are multiple stop bar positions on the centerline to indicate where different aircraft types will stop on the centerline. It is necessary because different aircrafts have different geometries and are needed to be parked a certain way to ensure safety.

The centerline and stop positions are determined after careful analysis of the airport layout and different aircraft types and sizes planned to be accommodated at different aircraft stands.

These lines ensure safe separation between aircrafts parked on adjacent stands as well as safe separation between aircraft and the jet bridge (passenger boarding bridge). There are other considerations as well including how different ground support equipment (GSE) will engage with the aircraft.

Pilots cannot keep the aircraft nosewheel precisely over the centerline nor stop the aircraft precisely at the designated stop position because they don’t have a clear visual of these markings on ground. Therefore, a marshaller is needed to guide the pilots to correctly park the aircraft.

Visual Docking Guidance System (VDGS)

Aircraft marshalling has been automated at most of the major international airports in the world by a piece of equipment known as Visual Docking Guidance System (VDGS).

It comprises an electronic display installed at the airport gate at the same level as the line of sight of pilots that provides visual cues to the pilot during parking.

The signals are displayed after laser scanners and onboard computer of the VDGS scans the aircraft and makes live calculations about aircraft’s orientation on ground.

Supplying Electric Power with AGPU

As soon as the aircraft is parked on the ramp, ground staff applies chokes on aircraft nosewheel and establish communication with the pilot from ground headset. Once pilot gives go ahead for engagement of ground power, staff connects the Aircraft Ground Power Unit (AGPU) with the aircraft.

After successful connection of ground power is made, pilots turn off the jet engines and aircraft uses ground power to keep the critical onboard systems on.

How Ramp Gets Busy

When jet engines are turned off, multiple ground support equipment invade the ramp and ramp becomes the busiest spot on the airport.

A Jet Bridge (Passenger Boarding Bridge) operator waits for signal from ground crew to begin PBB operation and connects the bridge with the aircraft within 5 minutes of receiving the signal. If Jet Bride is not available, mobile stairs are engaged to deplane the passengers.

Pre-Conditioned Air (PCA) unit is connected for providing fresh conditioned air to keep the atmosphere inside the aircraft comfortable for passengers and crew.

While passengers exit the aircraft, Belt Loaders (on narrow body aircrafts) and Cargo Loaders (on wide body aircrafts) line up with the aircraft cargo compartments to start unloading passenger luggage, cargo consignments and Unit Load Devices (ULD).

Cargo Dollies and Baggage Carts are loaded up and towing tractors are used for transferring all unloaded items to the baggage belts.

After unloading of cargo and baggage of arriving flight is completed, loading of cargo and baggage of departure passengers is started. When cargo and baggage loading is complete, all towing tractors, cargo dollies, baggage carts, belt loaders and cargo loaders are disengaged from the aircraft and driven away from the ramp.

Catering Truck is engaged with the aircraft when aircraft has become empty of passengers and airline staff start replenishment of catering supplies moving back and forth between the truck and galley (onboard kitchen).

Meanwhile, A Potable Water Truck refills the aircraft potable water tank and a Lavatory Service Truck drains the aircraft’s waste tank so that it is ready for the next flight.

Pilots check the fuel level of the aircraft and make a decision about whether or not refueling is required. If it is required, A Fuel Hydrant Dispenser parks itself under or near the wing of the aircraft for refueling.

In case fuel hydrant pits are not available at the airport, an Aircraft Refueler Truck is used for the same purpose.

Each ground support equipment (GSE) is disconnected and removed from the ramp as soon as it finishes its job because keeping the ramp clear of unnecessary machines and vehicles is an important measure for safety and efficiency.

In the end, Jet bridge, ground power unit (AGPU) and Pre-conditioned air (PCA) unit remain engaged until boarding is completed for the next flight. When last passenger boards the airplane and head count is completed, jet bridge is disconnected as well.

At this stage, if a dedicated deicing facility is not available at the airport, deicing and anti-icing of the aircraft may take place at the ramp during extreme winter conditions. Deicing trucks surround the aircraft and spray deicing and anti-icing fluids.

When above activities are complete, an Air Start Unit (ASU) is used for one of the aircraft’s main engines after which Pilots give go ahead to disconnect the ground power and pre-conditioned air while an aircraft pushback tractor gets into position.

After all Ground Support Equipment (GSE) have been disconnected and removed from the ramp, the final ramp operation is the aircraft pushback from the ramp using the Aircraft Pushback Tractor.

Pilot communicates with the control tower and receives go ahead for approaching the runway for takeoff. It marks completion of ground handling and ramp operations.

Other Ground Handling Operations

Ground handling operations are not limited to the ramp. It includes functions performed off the ramp as well including,

Although services provided at check-in counters, airport lounges and ticketing counters fall under airport services and passenger facilitation, they are often included in ground handling operations.

The Concept of Turn Round Time (TRT)

It is important to mention the concept of turn round time (TRT), a term commonly associated with ground handling and ramp operations.

As already described in the start of this article that an aircraft generates revenue flying and not remaining on ground. Aircrafts generally fly from destination to destination without long breaks. Therefore, the time duration in which all servicing activities are completed on an aircraft can become a bottleneck in revenue generation.

On one hand, aircraft manufacturers design aircrafts to make ground servicing as convenient as possible while airlines and ground handling agencies develop ways of completing all activities in such a well-coordinated and efficient manner that reduces the total time an aircraft needs to stay on ground without compromising safety.

This is where the concept of Turn Round Time (TRT) comes in. It refers to the time duration between successful parking of the aircraft and pushback operation i.e. the time duration an aircraft remains on the ramp.

All ground support operations have to be sequenced in a way to minimize idle time of GSE and reduce turn round time (TRT). The sooner the aircraft leaves the ramp for departure the better.

A benchmark turn round time (TRT) is available in aircraft manuals in which the manufacturer provides the optimal time and sequence of ramp operations for the specific type and model of their aircraft.

It serves as a reference for airlines and ground handling agencies to gauge the performance of their ramp services team and identify bottlenecks and areas where improvement is needed.

Turn Round Time (TRT) is optimized by conducting as many ramp operations in parallel as possible safely.

For example, passenger disembarkation can embarkation can take place simultaneously with cargo loading and unloading because jet bridge is engaged on left side of the aircraft while cargo loaders are engaged on the right side. These two ramp operations don’t interfere with each other.

However, some operations cannot be performed in parallel and it is important to sequence them properly.

For example, deplaning and catering replenishment are two ramp operations that cannot be performed simultaneously because replenishment of catering supplies requires movement of airline staff and trollies between aircraft and catering truck that is not possible until all passengers have left the plane.

Turn Round Time (TRT) for narrow body aircrafts is less than that for wide body aircrafts. Moreover, the level of training of ground staff and size of team also play a role in determining how quickly all ramp operations are completed and aircraft is made ready for departure.

So, this was it from our side. If you liked our article, don’t forget to share it with likeminded friends and colleagues.

Aviation Learnings

Learn How Airports Work

How Jet Bridge (or Passenger Boarding Bridge) Works? – A Complete Technical Guide

By Aviation Learnings Team

Jet bridge, also given many other names such as Passenger Boarding Bridge, Aviobridge, Aerobridge, Air Bridge, Jetway or Jetty, is one of the most important ground support equipment (GSE).

Today’s article is dedicated to explaining the jet bridge in great detail. By the end of this article, you are going to have a sound technical understanding of jet bridge.

What we’ll cover in this article

What is a Jet Bridge?

When an airplane lands at an airport, after passing through the runway and taxiway, it finally reaches at a place called an Aircraft Stand (also referred to as an aircraft bay). This is the place where passengers leave the airplane and enter airport building and this is where a Jet Bridge plays its role.

A Jet Bridge is simply a bridge on wheels that connects the airplane door with airport building. It is a movable structure powered by electric motors or hydraulic system for its movements and adjustments. It is also fitted with different types of sensors installed for safety of the bridge, airplane and people moving on ground around it. We will discuss more about the design of Jet Bridge later in this post.

History & Necessity of Jet Bridge

Airplane doors are at such a height that you need some sort of assistance to allow people to enter or leave the cabin. Historically, mobile aircraft stairs (also known as mobile steps) were used for this purpose.

A mobile aircraft stair is simply a staircase on wheels that adjusts its height with different aircraft types to align its level with the aircraft door and provide a safe passage to passengers to board or deplane the cabin.

However, mobile stairs do not protect the passengers from rain and bad weather. Nor do they offer any convenience in extreme hot summers. Moreover, it is not possible for mobile stairs to facilitate deplaning of passengers that need special care especially wheelchaired passengers.

The Jet Bridge was invented by Frank Der Yuen, an aeronautical engineer from MIT, born in 1912 and died in 1984. He patented the concept of jet bridge in 1962.

The purpose of a Jet Bridge is simple. It is to provide such a connection between aircraft and airport building that allows passengers to be embarked and deplaned from an aircraft in a comfortable and convenient manner that also requires less time and improves efficiency.

The concept of mobile bridges for passengers is not limited to aviation industry. Boarding bridges are used for passengers of a cruise ship as well as astronauts going on board on a rocket.

Jet Bridges make quite a weatherproof connection with the aircraft such that passengers are not exposed to outside weather conditions. It has its own air conditioning system to keep the bridge warm in winters and pleasant in summers.

Since a Jet Bridge connects at the same level as an aircraft building, it makes the activity of entering and leaving aircraft comfortable for wheelchaired passengers, senior passengers as well as other physically challenged passengers.

Apart from above reasons, exiting the airplane through mobile stairs and waiting for the bus to carry you to the desired airport gate can be a pleasant experience to someone new to the flying as you feel excited about looking at the airplane and all the activity that surrounds it from somewhere other than behind an airport window.

However, for frequent flyers or people uninterested in airport environment, it is not a pleasant experience because the weather is either too cold or too hot most of the times and there is a lot of noise at an aircraft stand. Passengers often complaint about the airline service if jet bridge is not used on the flight.

Have Jet Bridges Eliminated Mobile Stairs?

Although Jet Bridges have become the standard way of embarking and deplaning passengers, mobile stairs have not gone extinct. Every airport has a certain number of aircraft stands (or bays) that are called remote stands (also called hardstands or hard bays). They are given that name because they are located farther away from airport terminal building. These stands do not have the facility of jet bridges.

You may wonder why would an airport intentionally keep such an arrangement where jet bridges are not used?

The reason is that jet bridges occupy greater space as compared to no jet bridges. They also require greater infrastructure in construction of a gangway – an extension of airport building constructed especially for installation of a jet bridge (a handshake concept where the terminal building extends to reach the jet bridge while the jet bridge takes care of the path up to the aircraft door).

Consequently, airport gates that have jet bridges on them have to be constructed farther away from each other to accommodate the jet bridges and their supporting civil structure. That means less airport gates per given area because each gate is taking more space. That in turn reduces the overall capacity of an airport terminal building to accommodate maximum number of airplanes at any given time and that ultimately can translate to less money-making potential.

Due to the above reasons, when an airport is being planned and designed by consultant firms, they have to make a profitable compromise between quality of service and capacity of airport to accommodate as many flights as possible. This necessary compromise presents itself in the form of a preplanned split between contact stands (with jet bridges) and remote stands (without jet bridges) at the airport.

Remote stands are used by budget airlines trying to save on the expenditure by cutting jet bridge costs. In case of abundant traffic of flights, airport authorities may also provide jet bridges on first come first serve basis where the remaining flights may be accommodated on hard bays instead of waiting for an already occupied jet bridge to become vacant.

Moreover, hard bays are also used for parking private jets, business jets, cargo aircrafts and helicopters since they don’t have compatible jet bridges.

Main Components of Jet Bridge & How They Work

Now that we have looked into the history and necessity of jet bridges as well as their importance at an airport, let’s look at the jet bridge from a scientific perspective in terms of its basic components and working.

Different manufacturers use different nomenclature for different parts and components of their jet bridge. Therefore, the terms we have used in this post may slightly differ from a manufacturer’s manual, however, the concept will largely remain the same.

Things are about to get a little technical from here so bear with us.

There are 5 main components of a jet bridge namely Rotunda, Telescopic Tunnels, Elevation System, Cabin and Traction System.

A Jet Bridge starts with a Rotunda fixed over a Rotunda Column anchored into the ground. The function of rotunda is to act as an interface between airport building (a civil structure) and mechanical bridge (movable structure). Rotunda column serves as a strong foundation for the remaining parts of the bridge to be assembled over.

The interior of rotunda is designed to give it the same feel as airport building so that passengers don’t feel any difference. Its floor is fitted with carpet and roof with neat panels. Its circumference is installed with aluminum slats.

Telescopic Tunnels are the next part of bridge. They are supported by rotunda on one side and an elevation system on the other (we will discuss elevation system shortly). Telescopic tunnels are what make it a bridge.

The tunnel directly connected with rotunda is called a rotunda tunnel while the tunnel directly connected with cabin is called cabin tunnel (cabin will be explained shortly). Many jet bridges have more than 2 tunnels where intermediary tunnels are assembled between rotunda and cabin tunnel.

The term ‘telescopic’ is important here. Just like a telescope can be collapsed into a shorter length, the tunnels on a jet bridge slide inside one another to reduce overall length of the bridge. When all passengers have embarked on the airplane for departure, jet bridge telescopically collapses to draw back from the aircraft and create a safe separation between itself and aircraft fuselage.

Moving forward, the cabin tunnel is supported over an Elevation System. It comprises two metal pillars or columns side by side, assembled over a bogie (to be discussed shortly). Each column is actually a telescopic column with the ability to collapse or elongate.

The telescopic tunnels are fastened on both sides with these columns and telescopic action of these columns translates into raising or lowering the whole bridge to make it level with the aircraft.

This telescopic action is driven either hydraulically or mechanically. Jet bridges having hydraulic system to power their elevation system are called hydraulic bridges while those in which this elevation system is powered mechanically are called electro-mechanical bridges.

If you are wondering why there is any need to elevate or lower the bridge, let us give an explanation.

Since different aircrafts have different geometries, a single aircraft stand is designed to accommodate not one but a group of aircrafts. It is therefore imperative that a bridge designed to connect airplane door with airport building must be able to chase that door in different types of big and small aircrafts.

The aircraft door will be higher on some aircraft than the other parking on the same aircraft stand. Therefore, elevation system is a primary design feature of jet bridge that makes it compatible with a group of aircrafts arriving on the aircraft stand.

The elevation system columns described above are assembled over something commonly referred to as the ‘Bogie’. It is technically called the Traction System but is given the name ‘Bogie’ due to its likeness to locomotive bogie.

Bogie in jet bridge is responsible for all ground movements of the bridge. It mainly comprises two large wheels with each wheel having an electric motor and gearbox coupled to it for producing rotation. Both wheels move independent of each other.

When jet bridge has to be moved forward, both motors are energized by an electronic command given by bridge operator (like pushing control joystick forward). Similarly, a reverse command is given to rotate motors in opposite direction to move the bridge backwards.

The sideways movements are interesting because bogie wheels do not turn like wheels of a car do where you simply use a steering wheel to change the angle of your wheels and push the gas pedal to move in the new direction. Bogie wheels cannot change their angles because they are fixed.

The electronic control system of the jet bridge uses an algorithm to produce rotation. It energizes one motor in forward direction and the other motor in backward direction. The result is that the whole bogie starts to rotate in a clockwise or anticlockwise direction.

Once the angle of the bogie has been set as desired, operator gives the forward command and bogie starts moving forward in the newly assigned direction while carrying the whole bridge with it. Under such a case, the rotunda acts as a pivot or center of the circle in which bogie is moving.

Just like elevation system is responsible for making the level of jet bridge in line with the level of aircraft door, bogie is responsible for moving the whole bridge forwards towards the aircraft during arrival flights and reverse away from the aircraft during departure.

Remember we discussed the telescopic tunnels above that how they elongate and collapse?

The telescopic tunnels do not have any motors of their own to make them elongate or collapse. It is the bogie who does that. As the bogie moves forward, it elongates the telescopic tunnels. As the bogie moves backwards, it collapses the telescopic tunnels.

Bogie is therefore one of the most important parts of a jet bridge that is actually imparting it the ‘mobile bridge’ ability.

We hope we are able to explain technical things in easy to understand way so that you don’t feel you are being overwhelmed by technical jargons. Let’s move forward to the last part of the jet bridge.

At the end of the telescopic tunnels is the Cabin. Cabin is the part of the jet bridge that makes the final contact with the aircraft and makes the whole concept of ‘bridge’ possible. From the outside, cabin looks similar to rotunda i.e. a cylindrical shell, however, there is no pillar under it.

The role of cabin in a jet bridge is analogous to the role of cockpit in an airplane.

Cabin is fitted with the Operator Panel from where all movements of the jet bridge are controlled. The operator panel of modern jet bridges is very intuitive with a display screen, a few buttons and a joystick to maneuver the bridge.

The display screen shows the most important pieces of information to the operator including alarm messages, error codes and all parameters required for controlling the movements of jet bridge.

These parameters include the percentage extension of telescopic tunnels to make the operator aware of how much he has extended the bridge; the percentage extension of elevation system telescopic columns to make the operator aware of height of the bridge and angles of bogie, rotunda and cabin itself.

The joystick is similar to gaming console joysticks where the operator simply moves the stick in the direction he wants the bridge to move and the bridge’s control system translates that motion of joystick into electronic commands to electric motors of bogie to energize and move the bogie wheels in that direction.

There are three parts of cabin that play the most important role with respect to making engagement with the aircraft. These are cabin bumper, canopy and auto leveler.

Cabin Bumper is a cylindrical rubber located just at the bottom most protruded end of the cabin. It is intended to provide a soft scratch-free physical engagement between jet bridge and aircraft fuselage.

The operator maneuvers the bridge to make the cabin align with the aircraft door. During this alignment, operator has to precisely align the cabin bumper under the aircraft door such that when passengers step outside of the airplane, there is no gap between the aircraft door and cabin bumper in which someone’s foot could slip into.

To make sure such a gap isn’t present, the operator either softly touches the cabin bumper with the aircraft body allowing the rubber to compress a little and produce no mark or scratch on aircraft body or the operator keeps just a hairline gap between the bumper and aircraft body.

Apart from above, operator must not lower the bridge so much that the cabin is so much lower than the aircraft door that as the passengers step outside the aircraft, they feel they are stepping down a big step.

An expert and skilled operator will align the cabin bumper under the door of the aircraft such that passengers don’t feel they are stepping into a different platform as they exit the airplane door.

After cabin bumper has been properly engaged, the operator must engage what is known as the Canopy. As the name implies, canopy acts like a roof completely engulfing the exit door of the aircraft to prevent the exiting passengers from getting exposed to external weather.

Canopy is made of water proof fabric with padded ends to avoid any scratching on aircraft body as it makes physical contact. It is supported by belts passing over a roller driven by electric motors. These motors rotate in one direction to allow the canopy to fall forward and engage with the aircraft.

Similarly, motors rotate in opposite direction to pull the canopy back to its home position at the time of aircraft departure.

Since it is made out of fabric and padded material, it molds into the curvature of aircraft body and makes a proper seal around the aircraft door. It prevents rain, snow, dust, sunlight and wind from affecting the passengers exiting the aircraft. Moreover, it also saves losses in the internal air conditioning of jet bridge. It plays an important role in fulfilling the ‘protect passengers from outside environment’ part of the bridge.

After engagement of canopy, the last thing an operator does to complete arrival operation of jet bridge is to activate the Jet Bridge Auto Leveler.

Before we explain what an auto leveler is and what it does, let us explain what happens after jet bridge has been engaged. The key to understanding the important role played by auto leveler is in understand the dynamics of ground operations.

After an aircraft is parked at the aircraft stand and jet bridge is engaged, it is not only the passengers that exit the airplane. Their baggage and other cargo are also unloaded from the cargo compartment. So basically, a lot of load is being taken off the airplane.

To get this into perspective, a small passenger airliner like an Airbus A320 can easily carry over 100 passengers onboard. If each passenger weighs 75 kg (165 lbs.), combined weight of passengers alone is 7.5 metric tons. Add a few tons for their combined baggage and cargo as well and you can safely assume that an aircraft’s total weight reduces by 10 metric tons in the time duration is remains parked at an aircraft stand.

Just like your SUV rises up when you remove heavy luggage from its trunk, the aircraft’s height also changes when 10 metric tons of load is removed from its landing gear. It rises up!

What do you think will happen with the alignment of cabin bumper we discussed a few paragraphs above?

It is obvious that the aircraft body will rise but jet bridge will remain at the same height. It will create difference of height in airplane door and jet bridge level – something that is undesirable.

So, what is the solution? Should the operator keep adjusting the jet bridge’s height time and time again?

This is where the auto leveler comes in. As the name suggests, auto leveler is a sensor based assembly installed on one side of the cabin that allows the bridge to automatically adjust its level to the height of the aircraft.

It senses whenever aircraft changes height and automatically activates the elevation system of the bridge to maintain level of bridge with the aircraft door. In this way, once an operator has aligned the cabin bumper and canopy properly with the aircraft, bridge take it upon itself to maintain that alignment with the help of the auto leveler.

We will get into the engineering behind the electromechanical design of auto leveler assembly later in a separate post, however, the basic principle is that an arm and wheel assembly controlled by an electric motor and fit with sensors makes contact with the aircraft body.

As the aircraft rises, the wheel rotates and sends a signal to the jet bridge’s control system to make it aware of the change in aircraft height. The control system activates the elevation system to change bridge’s height until the wheel rotates back to its home position. As soon as the control system receives this signal, it stops further elevation. This is how an auto leveler maintains the height of the bridge at the same level as that of the aircraft.

Modern Technology in Jet Bridges

Jet bridges comes with many different technological features to protect not only the aircraft from possible accidents but also the ground handling and airline staff moving around the bridge to carry out different servicing tasks and activities in ground handling operation.

We are going to explain some of these technologies.

The Dead Man Switch

Another technological safety system used in jet bridges is the use of a dead man’s switch in joystick that controls the movement of the bridge. It is simple to understand its function.

The joystick won’t work until a lock is kept activated by the jet bridge operator. The lock is spring loaded and if the operator does not consciously keep pressure over it, it will release by itself and disable bridge movement irrespective of the direction in which joystick is being pushed. The dead man’s switch prevents unintentional movement of the jet bridge.

What can such unintentional movements be?

Therefore, dead man’s switch serves as a simple yet effective safety measure in jet bridge operation.

Aircraft Contact Sensing

To prevent collision between the aircraft and bridge, the cabin bumper is fitted with special sensors that detect if the rubber bumper is being pressed too hard with the aircraft body. These sensors detect the change in bumper shape as it is pressed between the bridge and the aircraft body.

As soon as the sensors detect this ‘pressing’ action, they send a signal to bridge’s control system that disables forward movement of the bridge even if the operator is pushing joystick forward.

Aircraft Proximity Sensing

Even before the jet bridge makes physical contact with the aircraft, some jet bridges also have Aircraft Proximity sensors to detect if the cabin is in close proximity to the aircraft body. If it is, these sensors send a signal to the bridge’s control system and the control system automatically limits the forward movement to lowest speed even if operator is pushing the joystick forward all the way. This safety system makes sure the bridge approaches the aircraft body very slowly to reduce risk of accident.

Wheel Bogie Obstacle Sensing

For the airline and ground handling staff present near the bogie, a special cage is available in some bridges to prevent running over a person or object. Where a cage is not available, a fence or some other form of protection is always kept.

Moreover, a special sensor system similar to cabin bumper sensor are also installed over the bogie that detects if something is coming in the way of bogie movement. The sensor sends a signal to the bridge’s control system when any human or material obstacle is felt and the control system disables any further movement. This safety system is basically a runover protection for people and objects moving on the ground around a jet bridge.

Anti-Collision System on Dual Jet Bridges

Where multiple jet bridges are installed on an aircraft stand to engage with both 1L and 2L doors of the aircraft at the same time, they have special sensors to detect the distance between the two bridges.

These sensors detect if the two bridges are coming too close to each other posing a risk of collision and send a signal to the bridge’s control system that disables any further movement towards each other. It is called an anti-collision system.

Auto-leveling Failure Backup

A special safety system is in place for fool proofing auto leveling system as well. It is called a ‘Safety Shoe’. It is a sensor assembly placed under the door of the aircraft on the floor of jet bridge cabin. It produces an alarm if the aircraft height is reducing during loading of cargo and passengers but jet bridge’s auto leveling system is not lowering the bridge.

Under such a scenario, the aircraft door presses the safety shoe placed under it and the safety shoe sends a signal to jet bridge’s control system that something is wrong. The jet bridge starts producing a loud alarm, drops a special platform to protect the aircraft door and automatically pulls the canopy back Basically, jet bridge tries to alert everyone around it that something needs serious attention.

Passenger Door Closure Sensing

Another important safety feature that needs to be mentioned is the cabin passenger doors safety system. The passenger doors on jet bridge are opened by the operator when jet bridge has been safely engaged with the aircraft door. These doors are closed after embarkation of passengers is complete and the jet bridge needs to be disengaged.

The door safety system comprises sensors that sense whether these doors are open or close. If the doors are not closed, the jet bridge control system disables any movement of the jet bridge. This safety system makes sure that a bridge is disengaged from the aircraft only when passenger movement is finished and these doors are closed.

Automatic Positioning or Prepositioning in Jet Bridges

A discussion on jet bridges cannot be complete without explaining the latest advances in jet bridge technology. Just like automation has become the next big thing in automotive industries in the form of self-driving cars, aviation technology has also been touched by automation.

Almost all major manufacturers of jet bridges are developing models capable of ‘self-driving’, however, the term commonly given to this type of operator-less automation in jet bridge industry is ‘Pre-Positioning’.

Pre-positioning in jet bridges refers to the functionality in jet bridge to operate itself and engage or disengage with the aircraft. All the movements that are performed by the operator in a manual operation are performed by the jet bridge itself when pre-positioning functionality is used.

Can you guess how pre-positioning would work? Maybe jet bridge has a camera that identifies the type of aircraft and move itself towards its door adjusting the cabin and bogie angle along the way with the help of sensors? No. It is easier than that.

Pre-positioning function can be set up only after jet bridge has been installed at an airport on an aircraft stand. The engineering team takes the geometry of all the different types of aircrafts the aircraft stand is designed to accommodate and figure out the parameters to be set inside jet bridge’s control system for making the cabin reach the level of aircraft door.

These parameters mainly include percentage of telescopic tunnel extension at which the cabin reaches the aircraft body and percentage height of telescopic columns of elevation system at which the cabin level becomes same with the level of aircraft door.

These parameters are calculated separately for all the aircrafts for which that aircraft stand is designed and the function activates when the operator selects an aircraft type from the operator panel interface. Moreover, operator has to remain inside the cabin during the whole operation to interrupt the pre-positioning functionality if he feels something is going wrong.

The operator’s presence is not kept just for monitoring and safety purposes. Pre-positioning function is not given complete freedom to engage cabin with the aircraft door. It is configured in a way so that the jet bridge reaches close to the aircraft and stops. It still keeps the operator’s job alive as operator makes the final touches and finishes the job.

Human supervision is necessary due to safety reasons. For example, it can be that the aircraft parked a little ahead of its stopping position or a little behind it. Pre-positioning system wouldn’t know the difference and would try to engage the jet bridge as if the aircraft is at its designated stop position and it may cause an accident.

You may wonder what is the advantage of pre-positioning when the operator has to remain inside the cabin as well as perform the final touches?

Although pre-positioning does not completely eliminate the need for a bridge operator, it significantly reduces human involvement such that more than 90% of the work is carried out by machine and 10% by human operator.

By reducing human involvement, pre-positioning reduces chances of human error and also saves time. A human operator relies on his judgement each time he engages the bridge with an aircraft. On the other hand, machine relies on simple math and minuses a big chunk of ‘human judgment’ factor from jet bridge operation that saves time.

So, this was it from our side. If you like this article, do leave your valuable feedback and share it with people interested in aviation technology. Let us know in the comments if you think we have missed something or something could be improved.

If you are interested in obtaining a base level knowledge about all the different types of aircraft ground support equipment and operations, Check out this 3 Hour video based course on Udemy that explains each of nearly 20 different aircraft ground support activities and equipment.

Ground support equipment

From Wikipedia, the free encyclopedia

Ground support equipment (GSE) is the support equipment found at an airport, usually on the apron, the servicing area by the terminal. This equipment is used to service the aircraft between flights. As the name suggests, ground support equipment is there to support the operations of aircraft whilst on the ground. The role of this equipment generally involves ground power operations, aircraft mobility, and cargo/passenger loading operations.

Many airlines subcontract ground handling to an airport or a handling agent, or even to another airline. Ground handling addresses the many service requirements of a passenger aircraft between the time it arrives at a terminal gate and the time it departs for its next flight. Speed, efficiency, and accuracy are important in ground handling services in order to minimize the turnaround time (the time during which the aircraft remains parked at the gate).

Small airlines sometimes subcontract maintenance to a larger carrier, as it may be a better alternative to setting up an independent maintenance base. Some airlines may enter into a Maintenance and Ground Support Agreement (MAGSA) with each other, which is used by airlines to assess costs for maintenance and support to aircraft. [ not verified in body ]

Most ground services are not directly related to the actual flying of the aircraft, and instead involve other service tasks. Cabin services ensure passenger comfort and safety. They include such tasks as cleaning the passenger cabin and replenishment of on-board consumables or washable items such as soap, pillows, tissues, blankets, and magazines. Security checks are also made to make sure no threats have been left on the aircraft. Airport GSE comprises a diverse range of vehicles and equipment necessary to service aircraft during passenger and cargo loading and unloading, maintenance, and other ground-based operations. The wide range of activities associated with aircraft ground operations lead to an equally wide-ranging fleet of GSE. For example, activities undertaken during a typical aircraft gate period include: cargo loading and unloading, passenger loading and unloading, potable water storage, lavatory waste tank drainage, aircraft refueling, engine and fuselage examination and maintenance, and food and beverage catering. Airlines employ specially designed GSE to support all these operations. Moreover, electrical power and conditioned air are generally required throughout gate operational periods for both passenger and crew comfort and safety, and many times these services are also provided by GSE. [1]

Jetway® Passenger Boarding Bridges

JBT, The Right Choice for Boarding Bridges

Passengers are at the heart of gate activities. Getting them on and off airplanes safely and efficiently is paramount. Doing so helps ensure satisfied customers as well as on-point airport operations.

JBT’s Jetway passenger boarding bridges excel at helping manage the flow of passengers, crew, and all their luggage and supplies. With so many features and options, Jetway boarding bridges can be tailored to your terminal requirements. A multi-decade lifespan, great service flexibility, and plenty of design options make Jetway airport bridges from JBT the ideal choice for gate boarding of your passengers.

It makes sense, then, that more than 9,000 Jetway passenger boarding bridges have been sold worldwide. What is it about JBT’s bridges that airport operators around the globe love? Here’s a sampling of rave-worthy elements:

And there’s more. JBT offers expert airport layout planning services. We specialize in creating boarding bridge and gate configuration designs that help you select the right gate boarding options for your needs and optimize aircraft parking at the gate.

Ultimately, the Jetway bridge from JBT is the perfect choice for any – and every – modern airport that serves regional aircraft up to jumbo jets.

Features & Benefits

JBT boarding bridges are feature-rich, consistently bringing exceptional value to your gate operations.

If you have any questions about these features or their benefit to your operations, contact us today.

Designed Better & Built to Last

You’re probably eager to streamline your ground support activities and eliminate unplanned downtime. These are obvious ways to minimize waste and maximize efficiency.

JBT is with you on this. That’s why we approach the design and construction of our products so rigorously and attentively. For example, our Jetway passenger boarding bridges are designed by licensed, Professional Engineers (PE) and built by welders who’re certified to AWS D1.1 standards. And, your JBT Jetway is NFPA compliant and tested for electrical connectivity and bridge movement and fit in our ISO 9001-certified factory.

We’ve purposely integrated functionality and durability – to boost productivity, preserve equipment longevity, resale value, and more – into every Jetway boarding bridge. Here are some examples of how JBT’s dedication to excellence works in your favor:

Gate Boarding Made Easy

Airport logistics are tough enough without having to hassle with confusing or awkward machinery. Fortunately, that’s not a problem with your JBT airport bridges. Here’s how we’ve made the Jetway simple to own and operate:

Boarding Bridges the Way You Want Them

Your JBT Jetway gives you incredible flexibility in design and aesthetics so you can have the perfect boarding bridge for your specific situation. This enables you to:

There are so many structural design choices with your Jetway bridges.

You also have options when it comes to appearance. JBT’s Jetway passenger boarding bridges are available in different materials and finishes so your boarding bridge fits your operational and aesthetic needs. You can opt for corrugated or smooth-sided steel, aluminum cladding, or glass (which can be tinted) exteriors. Final touches – like carpeting, radius strips, and plate threshold kits – can further enhance the looks, function, and durability of your JBT boarding bridge.

Premier Upgrades for Your Jetway Bridges

Go beyond the basics with these strategic upgrades. They’re not about getting fancy – they’re intended to facilitate your gate operations to reduce human error, speed up turnaround times, and more.

JBT’s Comprehensive AeroTech Solutions

JBT is ready to supply the products and services you require for your airport operations. Working with us makes tackling your lengthy and diverse task list much easier. It’s plain to see that JBT has your end-to-end aerobusiness needs covered.

The Right Equipment for the Job

Because you need to accomplish so many different tasks, JBT provides the products you need for gate and ramp operations.

Our offerings include everything from cargo loaders to tractors, scaffolding to simulators, and HVAC to power systems.

Equipment, and Then Some

JBT has more to offer you than world-class products. We’re also a renowned provider of Airport Services like:

Our mix of consulting, technology, and master technicians makes our service engagements invaluable.These are the elements that frequently unite operations, products, and personnel into a cohesive and effective system.

JBT, a Partner You Can Count On

No doubt, products and services are critical. However, they’ll never be the whole solution. It’s the people involved that make everything work. They get things to gel.

Taking the Long View

At JBT, we’re not going to sell you some equipment and services and move on. That doesn’t show you the attention and respect you deserve. And, it’s not how we want to do business.

Our aim is to build an enriching, constructive long-term relationship with you. This way, we can learn more about your business needs and serve you more thoughtfully and holistically now – and in the future.

Experts On Call

JBT entered the aviation support industry in the 1950s. We invite you to take advantage of all this experience and expertise. Let our top-notch team be your go-to resource!

We provide next-level support because we know running an AeroTech business can be complex, and you shouldn’t have to face the challenges alone. JBT knows the demands on the infrastructure, systems, and workers – and is ready to help you. So, don’t hesitate to contact us with questions.

Ground Support Equipment for Airports

Aviation is a busy industry. Lots of people rushing around doing lots of tasks. One key way leading airlines, airports, and cargo companies run smoothly is by leveraging the best available in aviation ground support equipment.

JBT AeroTech offers a full line of airport GSE. Whatever your tasks –

– we have the machinery you need to get them done properly, efficiently, and as quickly as possible.

We invite you to explore our innovative solutions — and imagine them smoothing your daily operations.

Aircraft Cargo Transporters & Loaders

Electric Ground Support Equipment (GSE)

LEKTRO® Aircraft Tugs

Tempest-i™ Deicers

BakTrak™ One Person Drive for the Tempest-i™ Deicer

Conventional Aircraft Tow Tractors

JetAire® M60 Mobile Conditioned Air Unit

Jetpower® Mobile Ground Power Units

AmpTek™ Load Sharing

Aircraft Passenger Steps

iOPS® Airport Operations & Equipment Monitoring Technology

If you have any questions about these products – or how they benefit your operations – contact our team today.

Why Choose JBT Ground Support Equipment

Investing in airport ground support equipment is not a decision to take lightly. You need to make sure you’re getting the best value for the money.

Relying on JBT GSE is a good place to start. Our ground handling equipment is well-known in the industry – for all the right reasons. On top of lower ownership costs and the best resale value, our airport ground equipment is loaded with features and options like:

What else does your JBT aircraft ground support equipment have going for it? A lot, and it’s all for your benefit.

Better Engineering, Better Operations

You require solutions that actually address the challenges you encounter on a daily basis. At JBT, we’ve taken that to heart and factored it into every hardware and software design.

Because of this, our aircraft GSE provides a rewarding array of features and functionality that you won’t want to do without:

JBT’s top-notch engineering means your AeroTech ground support equipment can serve you better. This translates into safer, more cost-effective, and more productive aviation operations.

Ground Support, the Easy Way

You have plenty of issues with the items on your everyday to-do list – worrying about the operation and maintenance of your GSE shouldn’t be among them.

That’s why your JBT ground support equipment isn’t well-constructed to just look and feel nice. It’s purposely designed for ease of use and ease of ownership. Across the board, you’ll find that JBT machinery has:

Durability for the Long Haul

Airports and cargo facilities are hubs of non-stop activity. You simply can’t afford to have your team or your equipment sitting idle due to failures and faults. We fully recognize this.

Consequently, JBT ground support equipment is built to last — no matter what tasks you set it to. With such solid construction, you can expect:

In short, JBT GSE is easy to operate, easy to maintain, and highly reliable.

Why Choose JBT

Yes, you have your pick of ground support equipment manufacturers. Opting for the one that’s going to serve you best clearly makes the most sense for your aero business. By selecting JBT, you’re getting reputation and results.

JBT’s comprehensive products, services, and support enable us to satisfy all your airport or cargo business needs, not just your GSE requirements. If you’re aiming for operations that run like a well-oiled machine – focus your gaze on JBT.

More Than Just GSE

Even excellent ground support equipment will only get you so far. JBT’s extensive portfolio also includes:

Our machinery’s hustling and bustling at airports all over the world. It’s proven – time and again, in a staggering breadth of environments – that it can handle doing what you need done.

For this reason, decision-makers and ground operators alike trust JBT’s equipment. We’re ready to outfit your operations with our first-class AeroTech solutions as well.

Leader in Airport Services

Market-making equipment is only part of the equation. To assist you in fully and optimally running your business, JBT also offers all-encompassing Airport Services:

So you get the best outcomes, our approach incorporates a smart mix of consulting, technology, skilled technicians, and more. JBT’s airport services may be just the ticket to tying your supplies, machinery, operations, and personnel together into a high-functioning, end-to-end system.

Your Aerobusiness Partner

There’s no doubt that managing an airport or cargo business is a complex, sometimes frenetic venture. Fortunately, you’re not out there alone. Working with JBT means you’ve got expert partners at your side.

Our job is to serve you to the fullest of our abilities, which certainly extends beyond the sales horizon. JBT seeks to forge enduring and collaborative relationships with customers. We’re pleased to play an active and facilitative role throughout the lifecycles of your operational needs.

Establishing such rapport gives JBT the chance to get to know you and your business. It lets us be both proactive and responsive to anticipate your needs, suggest options, and confront any bumps in the road. Having a long runway, so to speak, we can give you the attention and respect you’re due.

All the Solutions You Need – In One Place

When you land on an aviation equipment supplier that has all the products, services, and support you need – you’re in a good spot. JBT can be that strategic business partner for you today and into the future. Reach out to see how our comprehensive offerings can help your airport, aircraft, or cargo operations.