Skilifts.org - Glossary of Aerial Lift Terms

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Cable Tramway Terms

*Aerial Lift*	Any lift in which skiers are transported while suspended off the ground, as opposed to surface lifts, which move skiers and snowboarders up the hill while their skis or boards are in contact with the snow. Aerial lifts include chairlifts, gondolas and trams.
*Anti-rollback*	A mechanical system which prevents the weight of passengers on a lift from making the lift roll backwards in the event of engine or gearbox failure. Some modern lifts are designed to run in reverse for special purposes.
*Auxiliary*	A gasoline or diesel engine which allows the lift to run in the event of power failure or problem with the main motor.
*Guide Rail*	A guidance rail which high speed detachable lifts have that stabilize the carrier as it enters and moves around the terminal.
*BreakoverCord Angle*	difference in cord angles between towers. Also called breakover angle.
*Brittle Bar*	One of several devices used to detect a cable coming off the sheave wheels, a brittle bar is a metal bar connected to a safety circuit. Should the cable come off the sheave wheel, it strikes a brittle bar, breaking it. The interruption of the circuit causes the lift to stop. They are also used to detect overtravels on counterweights and to check proper positioning of certain grip components while passing through lift terminals. (see also Rope Position Detector).
*Brittle (Break) Fork*	The one in the picture are to stop the lift in case the counterweight is lifted to high, basically if anything comes into contact with them, they break - causing the safety circuit to open and the lift to stop.
*Bullwheel*	Large-diameter metal wheels used to change the direction of a haul rope. They're found at the top and bottom lifts.
*Cable Catcher*	A metal protruberance on the sides of sheave trains which catches the haul rope and prevents it from dropping to the ground, in the unlikely event that the haul rope comes off the sheave wheel.
*Cabriolet*	Mechanically and operationally, Cabriolet lifts are nearly identical to gondolas. The principal difference is that the carriers (cabins) are open, and passengers stand rather than sit. They tend to be rather short and are used primarily as "people movers," rather than to take skiers to the top. A Cabriolet lift was installed at The Canyons in Utah for the 2000-2001 season.
*Capacity*	Typically, this refers to the number of people who can board or disembark over a given period of time (typically one hour). Because of the speed with which skiers and snowboarders can successfully move up to the load line and/or safely disembark, capacity is typically limited on the upper end by the frequency with which carriers move through the terminals. (see Carrier Spacing). Current upper limits on double chairlifts is about 1200 persons per hour (2 persons every six seconds, which is twenty persons per minute, or 1200 per hour). Similarly, triple chairs have an approximate limit of 1800 per hour; and fixed grip quads can handle a maximum of 2400 per hour. Because detachable lifts (including detachable quads, six packs and gondolas) can actually have more than one carrier undergoing the load process at once, detachable lifts can load more than 3,000 per hour. See also: VTFH (Vertical Transport Feet per Hour).
*Carrier*	A generic term for the device on or in which customers ride. They can be chairs, gondola cabins, tram cabins, T-bars, etc.
*Carrier Spacing*	Can refer to either the time interval between carriers as they move through the terminal or the distance between carriers themselves. Typically, fixed grip lifts send a carrier past the load line every six seconds or so - a "six second" spacing. When used to describe distance, refers to the linear distance between the carriers. The design spacing is maintained on detachable lifts by means of a device called a spacer.
*Catenary*	The sag in the haul rope between towers.
*Compression Assemblies*	Compression Assemblies: An assembly of sheaves that support and holds down the haul rope. This type of assembly controls the haul rope for both positive and negative loads. This assembly is common in steeper spans with little slope change and at loading towers. Also called trap assembly.
*Chairlift*	Any form of open lift in which passengers sit in a chair while being transported. Some chairlifts have "bubbles," or fiberglass shells, which can be pulled down to protect passengers from inclement weather.
*Comm Line or Communications Cable*	This is the cable you generally see running down the middle of the lift, supported on the lift frame of the tower head. The comm line carries the data signals from each tower's safety and operating circuitry, as well as phone lines between the base, summit and mountain dispatch.
*Conveyor*	A system consisting of a track and drive system which transports carriers through the terminal on a detachable lift (gondolas, detachable chairlifts). Conveyors are usually powered by power takeoff wheels driven by the haul rope, to ensure that carrier spacing remains constant.
*Cord Angle*	The change of angle between the slope of the haul rope and horizontal; measured at the tower cross arm.
*Counterweight*	A massive weight at either the top or bottom of a lift, attached to the bullwheel, which keeps correct amount of tension on the haul rope - and therefore, the appropriate amount of friction between the haul rope and the wheel. Many new lifts are tensioned by either pneumatic or hydraulic tensioning systems instead of counterweights.
*Crossarm*	The horizontal arm on top of a tower, to which the sheave wheels are attached.
*Detachable*	A lift (gondola, chairlift) which detaches from the haul rope to go through the terminals. This process allows carriers to move slowly through the terminals, making it easier to get on and off, and travel rapidly on the line, giving skiers and snowboarders a fast lift ride. (See GRIP). Left: Picture of a detachable grip (Garaventa AK 400)
*Down-Line*	The side of the lift that the haul rope goes down the hill.
*Download*	The process of letting passengers ride down the lift, instead of up it. Many lifts are limited in their download capacity; others can transport passengers at 100 percent capacity in either direction.
*Drive*	The "brains" of the lift. The drive is the electronic circuitry which controls the amount of voltage sent to the primary motor of the lift and controls its speed. Modern lifts are powered by Direct Current, controlled by the drive, which allow them to operate very smoothly and efficiently. The drive is also tied in with all of the lift's inline safety circuitry, which shuts down the lift automatically in the event of a problem on the line or in one of the terminals.
*Drive Terminal*	The terminal which houses the motor, gearbox, auxiliary engine and drive and safety circuitry. It can be at either the top or the bottom of the lift ("top drive," "bottom drive.") A top drive lift is slightly more energy efficient than a bottom drive lift, but requires the ski area to run electric service to the summit, which can be very costly.
*E-Brake or Emergency Brake*	A brake which is used in emergencies to help stop the lift in case of a roll back or something drastic will happen. The brake is pressed up against the bullwheel which stops the lift with great force.
*Funicular*	A type of lift which uses a car traveling on steel rails, as a carrier. Most funiculars are "jigback" lifts, meaning that the weight of a car coming down counterbalances the weight of a car going up. Some funiciulars use two tracks, and some use just one, switching into two tracks in the middle of the line to allow the cars to pass. Most funiculars are in Europe. There are no funiculars at any North American ski areas, although there are several in urban settings (including Pittsburgh, PA and Quebec City).
*Funitel*	A comparatively new type of lift which is essentially a dual-monocable gondola with large cabins. The dual ropes make the Funitel capable of long spans between towers and makes the cabin less susceptible to wind. Only a handful have been built, mostly in Europe.
*Gearbox*	The lift's transmission. The gearbox takes power from the motor or auxiliary and transfers it to the bullwheel at the drive terminal.
*Gondola*	A type of lift which transports passenbers in multiple detachable enclosed cabins. Gondola cabins have ranged in size from as small as two persons to upwards of twenty. Modern gondolas use what's called "monocable" design, meaning that the haul rope both moves and supports the weight of the cabin and its passengers, much like chairlifts. Some older gondolas used a two-rope system, including a track rope (which supported the weight) and a haul rope (which moved the car). (See also: Track Rope, Haul Rope). There are two gondolas at Killington VT, and one each at Steamboat and The Canyons.
*Grip*	The mechanism by which the carrier is attached to the haul rope. Grips can be either fixed, meaning that the grip is clamped into a precise location and remains there, or detachable, meaning that the grip contains a complex system of springs and clamps which allow it to be automatically attached or detached to the haul rope in the terminals.
*Handle Tow*	A modern variant of the rope tow, which uses a thin wire rope (under high tension) and plastic handles, which skiers and riders hold on to while being towed up the hill.
*Haul Rope*	A wire rope which moves the carrier up the hill. In modern monocable design, it also supports the weight of a carrier and its passengers.
*High Speed Quad*	Generally used interchangeably with detachable quad. A quad chairlift with carriers which detach and slow for loading, reattaching them so that they can travel faster than a fixed-grip quad. There are at least two high-speed quads at each American Skiing Company resort.
*Hold down assembly*	An assembly of sheaves that hold down the haul rope. Also called depression assembly.
*In-Line Tower*	Any lift tower which is not also a drive or return terminal. Towers are typically numbered, which makes them handy landmarks.
*J-Bar*	A type of surface lift created in the '40s. J-Bars hang from wire ropes which are suspended by towers. A metal tube hangs down from the grip, and ends in either a horizontal or slightly curved appendage at the bottom (hence the "J"). Skiers place the horizontal appendage under their butts and get towed up the hill. Sitting down on a J-Bar virtually guarantees falling off the lift. There are still a few J-Bars around today, although they're quite rare. Picture thanks to Colorado Ski History Museum.
*Jigback*	Any type of lift with just two carriers that counterbalance each other. One carrier goes up while the other goes down, and vice versa. Jigback lifts include Funiculars and Trams.
*Lift Frame*	The superstructure on top of an in-line tower, to which mechanics can attach a device to hoist the haul rope for maintenance or repair purposes.
*Line*	A broad term for the area of the lift between the terminals, including the inline towers, the tower heads and the sheave trains.
*Line Check*	An inspection of the line of the lift by ski area personnel, done by riding the lift. On the line check, the inspector observes the behavior of the lift and looks and listens carefully to each tower, to ensure that everything is functioning properly.
*Line Speed*	The speed at which a haul rope travels. A fixed grip chairlift usually has a line speed of between 400 and 500 feet per minute; Poma lifts can approach 700 feet per minute, and modern detachable lifts can travel more than 1,000 feet per minute.
*Loading Area*	The area between the lift maze and the lift portal (the last stage of the load terminal before you're out on the line). There's lots going on in the loading area - pay attention to what's going on around you!
*Load Line*	A line, designated either by signs on either side or by a board placed in the snow, on along which all passengers loading a chair should be aligned just before boarding a chairlift or surface lift. Having everyone evenly aligned makes it easier for the lift operator to give everyone a smooth load.
*Load Test*	The process by which ski areas and state lift inspectors test lifts to ensure that they're cabable of running in accordance with design parameters. Typically, boxes lined with trash bags are placed in chairs and filled with water to a point where the lift is loaded with more weight than it would typically sustain in normal operation. The lift's capacity to start, stop and prevent a rollback is then evaluated. Every new lift undergoes a load test prior to being put into service, and all aerial lifts are load tested periodically according to the tramway laws in their state.
*Maze*	The area in which skiers and snowboarders gather while waiting to board a lift. Mazes are designed to optimize chairlift loading. Skiers and riders often call mazes "lift lines."
*Magic Carpet*	A brand name for a type of surface lift which is rather like a conveyor belt. Skiers and snowboarders simply step onto the surface, which is a continuous belt. Magic Carpets are more typically found in children's areas, but some ski areas also use them for beginning adults.
*Midstation*	A structure somewhere on the line of the lift, between the top and bottom terminals, which allows skiers to either load, unload or both.
*Offset Tower*	A tower that is offset from the normal center-line of the lift. The offset can help by providing a wider run for the skier. The tower cross arm is normally missing the down-line assembly. The lack of an assembly helps the manufacturer reduce costs. Also the larger down-line span helps absorb the energy generated by stops and starts in a lift with a fixed carriage.
*Pomalift*	A type of surface lift invented by French engineer Jean Pomagalski.. Like T-Bars and J-Bars, the Pomalift utilizes an overhead cable suspended by towers, from which metal bars descended. But unlike T-Bars and J-Bars, which pulled passengers up the hill by means of a bar placed under their butts, a Pomalift stick has a six-inch plastic disc at the bottom. The stick is placed between the skier's legs (Pomalifts are a dismal experience on a snowboard), with the disc under the butt. Pomalifts were in many regards the first widely-used detachable lifts; the sticks stop in the bottom terminal, and the grips are designed in such a way that the haul rope runs freely through them while the Poma stick awaits its next passenger. Once the skier is at the load line, the operator hands the skier the stick, then trips a lever which kicks the Poma stick forward. This action and the skier's weight creates a slight kink in the haul rope, which results in sufficient friction within the grip to allow the stick and disc to pull the skier uphill. There are also fixed-grip versions, often called platter pulls. Except for fixed-grip versions found in beginner areas, Pomalifts tend to be quite fast - faster, in fact, than fixed grip chairlifts. They're still quite common in Europe, but they never really caught on in the US, although there are still a few around. Jean Pomagalski went on to found the Poma Lift Company, which is still one of the major manufacturers of modern lifts in the world today. The company was recently sold to Leitner, another lift company.
*Portal, Portal Area*	The area between the legs of the uphill end of a bottom terminal.
*Prime mover*	The motor that is the primary mover of the lift. It can be gas, diesel or electric. It may not necessarily be the motor with the highest horsepower.
*Pulse Lift*	A type of aerial lift most commonly seen in Europe. Pulse lifts feature widely-spaced series of carriers - typically, gondola-type cars -- permanently gripped together in a train. The lift must stop at the terminals (hence the term "pulse") to load and unload. These are comparatively low-capacity lifts and are rarely built today.
*Retention Bar*	A device which can be lowered to help retain skiers and snowboarders in the chair on a chairlift. The presence of Retention Bars on chairlifts - and their use by passengers - is required by law in some states, including those in New England. They are not required by law in others, including Colorado, Utah and California, although they're found on may lifts in those states.
*Return (or Return Terminal)*	The terminal at the other end of the lift from the drive terminal.
*Rime*	The formation and buildup of ice on a lift. This can take many hours to get the lift moving properly again.
*Rope Position Detector*	Another type of safety device used on some lifts to ensure that the haul rope is properly aligned. They're essentially metal detectors, and can detect movements in the haul rope of as little as _ inch. In the United States, they're required on all aerial lifts which travel more than 600 feet per minute.
*Rope Tow*	Although winter sports enthusiasts had used trains, funiculars and other forms of conveyance in the Alps to ascend mountains earlier, the rope tow was the first true uphill conveyance designed specifically for skiing. Essentially a large diameter rope spliced together at both ends, the rope tow was powered by an engine or motor (early ones used car axles), which pulls the rope uphill. On the downhill side, the rope was typically held off the ground by means of wheels (often automotive tire rims) attached to towers (typically worn-out telephone poles). A low-tension device, the rope runs along the ground until a skier picks it up. Early rope tows used natural fiber ropes, which picked up water and made them both heavy and slippery. More recent ropes for rope tows are synthetic fibers. There are still a few rope tows around; they're more likely to be found at small and community ski slopes.
*Rotation*	Left-hand-up: Rotation of the lift will have the up-line on the left side as you face up hill. Also called left-hand. *Right-hand-up*: Rotation of the lift will have the up-line on right side as you face up the hill. Also called right-hand.
*Safety Gate*	A device - usually a rope, metal bar or laser - at the top of lifts, hooked into the lift's safety circuitry. If a skier or snowboarder fails to unload properly, they'll trip the rope or bar, which throws a switch and stops the lift. If you ever have trouble getting off a lift, do NOT try to avoid this device - blast through it bravely, knowing that your troubles are nearly over!
*Sheave loads*	Weight is controlled by design/code loads. Typically the average is not more than 500 lbs. per sheave. As loads approach 250 to 0 lbs. a compression assembly is used. If loads exceed 500 lbs. - more sheaves per assembly and or larger diameter sheaves are used. If negative loads are required, hold down assemblies are used. Some hold down assemblies are support assemblies turned upside down. Minimum loads on sheaves are needed to counteract side loads such as swinging carriers and wind.
*Sheave Train*	A series of sheave wheels, located on the crossarm of an in-line, top or bottom terminal. They're typically mounted in assemblies known as "Walking Beams," which allow the wheels to move up or down in response to the weight of the carrier and its passengers.
*Sheave Wheel*	A metal wheel, lined with a special type of rubber, which either supports or depresses the haul rope.
*Six-Pack*	A six-passenger high speed chairlift. Some lift companies are now making 8-passenger high speed chairlifts.
*Slope Length*	The linear distance covered by a lift. Think back on right triangles from your high school trigonometry class: the vertical rise of the lift is the vertical leg of a triangle, and the slope length is the hypotenuse.
*Spacer*	A device on modern detachable lifts (gondolas and high speed chairlifts) which can advance or retard the speed a carrier as it moves through a terminal, in order to keep the proper distance between carriers.
*Splice*	The process of weaving one end of a rope smoothly into the other in order to create a continuous loop. Also: the area of a haul rope which has undergone a splice. The splice on a modern lift is generally about 120' in length.
*Support Assemblies*	An assembly of sheaves that hold up the haul rope from the bottom side. Also called breakover assembly.
*Support Tower*	An in-line tower on which the sheave train supports the haul rope, rather than depressing it.
*Surface Lift*	Any lift on which the skier or snowboarder's skis or board remains in contact with the snow. Surface lift types include Rope Tows, Handle Tows, J-Bars, T-Bars and Poma Lifts.
*T-Bar*	A surface lift similar in design and concept to a J-Bar, only with a T-shaped fitting at the bottom to allow two skiers to ride side by side. The device essentially tows you up the hill, and sitting down on it is always a mistake. Getting your boot buckles tangled with those of the person riding next to you is always interesting. Tall adults riding with small children have even more fun.
*Tensioning System*	A device which keeps correct amount of tension on the haul rope - and therefore, the appropriate amount of friction between the haul rope and the wheel. Many new lifts are tensioned by either pneumatic or hydraulic tensioning systems instead of counterweights. Also see *counter weight*.
*Terminal*	Generally, the structures at the top and bottom of the lift, where skiers and riders load and disembark. Some lifts, such as multi-stage gondolas, also use in-line terminals or mid-stations.
*Terminal Speed*	The speed at which a carrier goes through a terminal. On a fixed grip lift, terminal speed is the same as line speed. On a detachable lift, it's slower.
*Tower*	Any structure which either supports or compresses the haul rope. Most towers today are "tubes," or pipe. Towers on older lifts, and also very tall towers such as those used on trams, are typically constructed in lattice fashion. Towers are anchored to massive blocks of concrete, which are either buried in soil or pinned to rock. Lift manufacturers and ski areas also consider the terminals at either end of a lift to be towers.
*Tower Head*	The assembly at the top of the vertical portion of a tower, including the cross arm, the sheave trains and the lift frame.
*Track Rope*	A smooth wire rope with the sole function of supporting a carrier. The carrier rides along the track rope on small wheels, which wrap around it. Lifts which have track ropes also have haul ropes to move the carrier. Track ropes are found on older-style (non-monocable) gondolas and aerial tramways.
*Tram*	Webster's defines "tram" as "the carriage of an overhead conveyance;" technically, gondolas and chairlifts are trams. But skiers typically use the term to describe large "jigback" style aerial lifts - which look rather like aerial buses. Modern trams are generally used in areas in which terrain limits the ability to place in-line towers - either for topographic reasons (such as large cliffs) or to span environmentally sensitive areas. There's a tram in New York City which spans the East River and connects Manhattan with Roosevelt Island. Trams are invariably supported by track ropes and moved by means of haul ropes. While their cabins can be quite large - there are double-decker trams in Europe which can hold more than 200 passengers - the fact that there are only two carriers limits their overall hourly capacity. Despite this, they're remarkably energy efficient; the two carriers counterbalance each other, just as with a funicular. The tram in Palm Springs, California, a massive lift which rises nearly a vertical mile over a length of just over two miles, needs only a few hundred horsepower to operate.
*Unload Area*	This is the area located from the unload point of a lift and down the ramp to a safe distance away, so the next passengers can safely disembark. Always move quickly out of an unload area.
*Up-line*	The side of the lift that the haul rope goes up the hill.
*Vertical Rise*	The difference between the elevation at grade at the bottom terminal and the elevation at grade at the top terminal.
*VTFH (Vertical Transport Feet per Hour)*	A technical term used by lift manufacturers and some ski areas to describe a given lift's capacity. Essentially, it refers to the vertical rise of the lift times the number of persons who can ride it in one hour. For example, a high-speed quad which has a vertical rise of 1000 feet and an hourly capacity of 3000 has 3 million VTFH.
*Wire Rope*	A replacement for hemp rope, see *haul rope*.