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Ultimate Rollercoaster > Roller Coasters > Glossary

ROLLER COASTER GLOSSARY

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List of definitions for words and terminology commonly used to describe the parts and elements of a Roller Coaster and the ride experience.

|# |A |B |C |D |E |F |G |H |I |J |K |L |M |N |O |P |Q |R |S |T |U |V |W |X |Y |Z |

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4th Dimension - Term used to describe Arrow Dynamics 4th Dimension roller coaster where the individual cars of the roller coaster train are designed to independently flip on a horizontal axis in a controlled manner. An example is the X roller coaster at Six Flags Magic Mountain.

A

Acceleration - Describes when the coaster's cars or trains are gaining speed. The term is most commonly used to describe how fast a train reaches a specific speed on a launch coaster (i.e. the train accelerates from zero to XX mph in X number of seconds).

American Coaster Enthusiasts (ACE) - American Coaster Enthusiasts is the largest club of roller coaster and amusement park enthusiasts. Membership is open to all. The club's annual fee includes a membership card, access to club sponsored events and a publication.

ACE Coaster Classic - Describes a roller coaster designated by the American Coaster Enthusiasts (ACE) that meet certain requirements as prescribed by the club. Roller coasters designated as a coaster classic are believed to retain the "original classic" riding experience.

Air Gate - A crowd control gate that prevents people from walking onto the roller coaster's loading platform. These are installed for safety purposes and in some cases are driven by compressed air.

Airtime - Term used to describe the feeling created by negative G-forces. Airtime is the sensation of floating while riding a roller coaster when your body is forced up from the seat creating air between the seat and your bottom. Airtime or negative G-forces are most commonly experienced on a drop or at the crest of a hill.

Anti-Rollback Device - A ratcheting mechanism used on a lift hill or section of a roller coaster that prevents the cars or trains from rolling backwards. This is the device that causes the familiar clicking sound on many lift hills.

Ascend - To rise up a hill, tower or any incline.

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B

Backwards - This term refers to riding a roller coaster while seated facing in the opposite direction you are traveling. Amusement parks will on occasion run a roller coaster backwards by placing the train backwards on the track so the rear car leads. On shuttle coasters riders will travel backwards and forwards since the roller coaster track does not form a complete circuit.

Banked Turn - Describes a section of track that is banked (laterally angled) while turning. Designers bank the turns on roller coasters to reduce the lateral G-forces.

Barrel Roll - An inversion term most frequently used by Bolliger and Mabillard to describe what is basically a corkscrew inversion on their roller coasters. See related term: corkscrew

Batwing - Arrow Dynamics term for a boomerang inversion, which consists of two half vertical loops, each at a 45 degree angle, with half the inversion facing each other. See related term: boomerang, cobra roll

Bench Seats - A flat-seat designed with no divider between the riders. Bench seats were common on older wooden coasters and mine train coasters. A bench seat allows riders to slide across the seat. Today, most coasters are designed with seat dividers or bucket seats to meet modern safety concerns.

Bents - The vertical wood beams on a wooden roller coaster's structure.

Block - Used to describe a section of track on the course of a roller coaster. Blocks are separated by brakes, lifts, stations or other devices that enable a train to be stopped and most coasters are designed to operate with only one train moving in each block at any time.

Boomerang - A type of inversion with two half loops connected to each other. Boomerang is also the term used by Vekoma to describe one of their shuttle coaster models. Also see Batwing, Cobra Roll

Bowtie - A term used to describe an inversion similar to a boomerang inversion, but in a bowtie inversion the train enters and leaves heading the same direction.

Brake Fin - A straight piece of steel found on the underside of the roller coaster car that slides into and through a fin brake mounted on the tracks. The brake fin may also slide through a magnetic brake as well.

Brake Run - A section of track usually before the loading station where brakes are installed to bring the incoming trains to a complete stop. Brake runs may also be installed midway through the course.

Brakes - A device used to slow or stop the train on a roller coaster. Brakes are placed on the brake run, but may also be located along the course the train travels to slow the train down if necessary or stop it at a block. Related terms are block brake, trim brake and brake run. Types of brakes include skid brakes, fin brakes, and magnetic brakes.

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C

Camel Back - A series of hills on a steel or wooden roller coaster where each preceding one is slightly smaller. Camel backs produce negative G's or "air time".

Car - A car is a part of the overall coaster train. A car consists of one or more rows where riders are seated in individual or bench seats. A coaster train should consist of two or more cars linked together to form the train. Coasters that operate with only one car do not use the term train, but instead refer to the vehicles as individual cars.

Car Barn - An enclosed or partially enclosed structure used to house the roller coaster cars or trains when they're not in use. The car barn may also house the roller coaster's maintenance area.

Catapult Launch - The coaster train is launched to give it power instead of using a lift hill and gravity. The catapult system connects with the train and accelerates the train using a flywheel or weight drop. More recently compressed-air (Thrust Air), Linear Synchronous Motors (LSM's) and Linear Induction Motors (LIM's) are being used as well to launch a train.

Chain Lift - The chain lift is one of the fundamental elements of most roller coasters. The chain lift pulls the car or train to the top of a hill and then releases the train to coast down a hill where the train accelerates and gains its momentum to complete the course. On some coasters more than one lift hill may be used.

Check Brake - A type of brake used to stop the train if necessary. The check brake will engage if a train is going to enter a block on the circuit that another train is currently is traveling in. These are devices used to protect a block from having more than one train operating in them at once.

Circuit - Used to describe a complete roller coaster track from start to finish.

Cobra Roll - A term describing a signature element on some roller coasters designed by Bolliger and Mabillard. The cobra roll is a double inversion similar to Arrow's boomerang element. Riders are enter the element and are sent upside down twice and leaving going in the opposite direction they were as they entered. The design of the element looks like the hood of a striking cobra.

Compressed Air Launch -

Corkscrew - A corkscrew is a twisting inversion designed like a corkscrew. Arrow Dynamics designed the world's first corkscrew inversion. Barrel roll is the term used by Bolliger and Mabillard to describe their corkscrew inversion.

Cutback - Designed by Arrow Dynamics this element includes a single inversion and a 180-degree turnaround.

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D

Diving Loop - A term used by Bolliger and Mabillard to describe an inversion similar to an acrobatic stunt plan maneuver. This inversion involves half a vertical loop and a twisting curve leading either in or out of the inversion. On the B&M; inverted coasters this inversion is referred to as a Immelman. See related terms: immelman

Double Dip - A hill that has been divided into two separate drops by a flattening out of the drop midway down the hill.

Double Loop - A term used to describe an element of two vertical loops together or may be used to describe a roller coaster with two vertical inversions, and no other inversions.

Double Out and Back - A term used to describe the layout on a roller coaster where the track heads away and returns to the station twice. See related terms: out and back, triple out and back

Dual Track - The term used to describe a roller coaster with two different tracks or circuits. A dual track coaster shares the station and may share some parts of the structure including the lift hill. Related term: mobius

Dueling Coaster - A dual track roller coaster that is designed to produce the effect of near, head-on collisions through the circuit. Examples of a dueling coaster include Twisted Twins at Six Flags Kentucky Kingdom, Gwazi at Busch Gardens Tampa and Dueling Dragons at Universal's Islands of Adventure.

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E

Elevated Curve - A curve on a roller coaster where the track either descends or ascends as it curves.

Enclosed - A roller coaster where the entire track is housed inside a building or some sort of structure. Theme parks generally build coasters inside a structure so they may theme the ride with lighting, sound or other special effects.

Exclusive Ride Time (ERT) - The term used by coaster clubs to describe the exclusive period of time where only members may ride the thrill ride or roller coaster. ERT usually occurs before the park opens or after the park closes.

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F

Fan Turn or Fan Curve - A turn on a wooden coaster designed with a sweeping curve from the entrance to the exit of the turn. Fan curves are usually used to describe a change of direction of less than 90-degrees and turn is used to describe a change of direction of 90-degrees or more

Figure 8 Layout - A roller coaster track layout that resembles the number eight from above.

First Drop - The first major drop on a roller coaster and generally the first drop following the lift hill.

Fixed Lapbar - A restraint on a coaster train that a rider sits under that locks in a designated position and does not adjust. Because of an increase in safety awareness fixed lab bar restraints are being replaced by individual rachetting lap bars.

Flat Spin - A term used by coaster designers Bolliger and Mabillard (B&M;) to describe their banked, high-speed helix turns.

Flat Turn - A turn where the track remains flat and gives the sensation that the train my tip due to the lateral forces. Most turns on a coaster are banked, but in some cases a flat turn may be used to increase the thrills. GhostRider designed by CCI features a flat turn above the station before the mid-course block brakes.

Floorless -

Flywheel Launch -

Flying Turns - The original term used to describe a bobsled roller coaster. Flying Turns was a wooden coaster with a trough that a train descended in. There is no track so the train is free to move within the U-shaped trough.

Freeform - A term used to describe a custom, unique layout for a roller coaster. Freeform coasters may use the terrain or the designer may have simply chosen to create a unique layout.

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G

G-Force -

Galaxi - A portable steel roller coaster with a compact twister layout. These coasters were common at fairs in the 70's and 80's. See related terms: Wildcat, Zyklon

Gigacoaster - A marketing term used by Cedar Point and manufacturer Intamin to describe a roller coaster that stands more than 300 feet tall. Millennium Force a 310-foot tall, 92 mph hypercoaster at Cedar Point is the example.

Guide Wheels - These are a set of wheels that guides the train in turns and prevents the train from falling off the rail or track. Guide wheels are attached to the underside of the car or train and run along the inside or outside of the track.

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H

Headrest - Headrests are a part of the design of a coaster seat. This device is added to some coasters for rider safety to prevent whiplash.

Heartline - A term used to describe an inversion where the center of gravity is designed around the riders heart line. TOGO was the first company to design a heartline inversion on Viper at Six Flags Great Adventure. Bolliger and Mabillard calls a heartline inversion a zero-G roll.

Helix - A turn on a roller coaster course that forms a radius of more than 360-degrees.

Hydraulic Launch -

Hypercoaster - A term used to describe a steel roller coaster designed for speed and airtime. Hypercoasters have large drops for speed, have no inversions and have plenty of camelbacks, bunny hops or speed bumps for airtime.

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I

Immelman - A term used by Bolliger and Mabillard to describe their Diving Loop on inverted roller coasters. This element was named for an airplane manuever invented by a German pilot in World War II.

Incline Loop - A term used by Bolliger and Mabillard used to describe a vertical loop which is angled at an elevation of sharply less than 90-degrees.

Individual Lapbar - A restraint designed for an individual rider. The lapbar restraint will lock into position directly across the riders lap, securing the rider for the duration of the ride.

Indoor Roller Coaster - An indoor roller coaster operates inside a building, such as an indoor amusement park, mall or other venue.

Inversion - A term used to describe any portion of a roller coaster track that turns the riders upside down.

Inverted Roller Coaster - A roller coaster with trains suspended beneath the track above. The first Inverted Roller Coaster was Batman The Ride at Six Flags Great America (1992) and designed by Bolliger and Mabillard. Vekoma followed with its version of the Inverted Roller Coaster, but instead calls it a Suspended Looping Coaster.

Interlocking Loops - Two vertical loops that are interlocked or are connected like links on a chain. The Lochness Monster at Busch Gardens Williamsburg was the first roller coaster to feature Interlocking Loops.

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K

Jet Star - A production-model steel roller coaster with a twister layout designed by Anton Schwarzkopf. There are several variations of this type of Schwarzkopf coaster, which are called Jet Star, Jet Star II, and Jumbo Jet.

Junior Coaster - A term also used to describe a kiddie coaster or a simple roller coaster designed especially for children.

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L

Lapbar - A type of restraint that secures the rider by placing a bar across the passengers lap. Lapbars are the most common form of restraint used on amusement park rides. A Lapbar restraint can be designed to secure an individual rider or multiple riders.

Lateral G's, Lateral Forces, Lateral Gravity - Forces experienced on a roller coaster that pull your body to the side of the car. The lateral forces are found in flat turns, and on some helix turns. The less banking in the turn the more intense the lateral forces will be.

Lifthill - The section of the coaster that contains some device or mechanism that pulls or pushes the roller coaster train up a hill. The majority of lifthills uses a chain connected to a motor that pulls the train to the top. Some roller coasters contain multiple lifthills and the lifthill may be midcourse or at the end of the circuit.

LIM or Linear Induction Motor - A magnetic motor commonly used to launch a roller coaster train along or up a section of steel track. LSM or Linear Synchronous Motors are the same idea, but the technology used to propel the train is different.

Looping Corkscrew or Loop Screw - A type of roller coaster that features a vertical loop and a corkscrew.

LSM or Linear Synchronous Motor - A method used to launch or accelerate a roller coaster train along a straight section of track of hill. This technology used magnetic electrical waves to attract and repel magnets mounted on the underside of the train.

Loading Platform - The part of the station where the riders board the roller coaster train.

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M

Manual Brake - A hand operated brake requiring a human to operate that slows or stops a roller coaster train. Many classic wooden roller coasters have manual brake systems, but in recent years they're becoming rare as parks replace the manual brakes with computerized brake systems.

Mine Train - A genre of early steel roller coasters with a layout that features fast, quick turns, drops and helix turns. Many are themed after a runaway mine train.

Mobius Track - A racing roller coaster where the track forms one continuous-circuit and passes through the station twice. There are only a few mobius track roller coasters still operating in the world and they are, The Racer at Kennywood, El Serpiente del Fuego at La Feria de Chapultapec Magico and The Grand National at Blackpool Pleasure Beach.

Multielement - A term used to describe a roller coaster with multiple inversion elements.

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N

Negative G's - Negative G's generate airtime or the sensation of floating while on a roller coaster. Negative G's are usually found on a roller coaster at the top of a hill when the riders body is accelerated upwards.

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O

Out and Back - A term used to describe a type of layout on a roller coaster. An out and back roller coaster layout is where the train leaves the station and heads out to a point where there is a turnaround to send the train back to the station. Sometimes variations can be found like an L-layout out and back where the turnaround is not the only curve in the roller coaster. Some out and back coasters like Shivering Timbers at Michigan's Adventure will have a helix at the end of the layout, but still maintain a correct out and back layout.

Oval Track - A roller coaster track layout that forms an oval shape, which is a very common layout for junior roller coasters.

Over-The-Shoulder Restraint (OTSR) - A device that goes over the riders shoulders to restrain and protect them while riding a roller coaster. Most looping roller coasters like Viper at Six Flags Magic Mountain have over-the-shoulder restraints.

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P

Partially Enclosed - A roller coaster where only a portion of the track is within an enclosed structure or building.

Pay-One-Price - Amusement Park admission structure where you pay-one-price for all rides, shows and attractions and is often called a POP ticket. The other option if available is to pay-as-you-go, in which case you'd use tickets for the rides, attractions and shows. Disney Theme Parks are examples of POP admission parks, and Knoebels Amusement Park is an example of a park that has POP as an option on selected days, but always offers the option to pay-as-you-go.

Point of View (POV) - The roller coaster experience as seen from the rider's point of view. This term is often used with video footage or animations to describe the type of footage. POV footage is taken on the ride, generally in the first or last rows and shows the what the rider experience is like on the ride.

Positive G's - Gravitational forces that pull you downward that are often found in inversions, highly-banked, high speed turns and at the bottom of hills. Positive G-forces are when the gravitational force exceeds 1 G giving you the sensation of feeling heavier than you actually are.

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R

Racer - A dual track roller coaster designed where the trains leave the station at the same moment and race each other through the circuit. Most racing coasters like Colossus at Six Flags Magic Mountain feature parallel tracks. Other coasters like Rolling Thunder at Six Flags Great Adventure or Lightning Racer at Hersheypark race, but each track is entirely different.

Ratchet - A toothed steel bar or device that is usually placed on the lift hill or other hills on a roller coaster that prevents the train from rolling backwards when the ratchet dog (anti-rollback device) attached under the car engages with the ratchet in the steel bar.

Restraint - Some sort of device to prevent the rider from leaving the roller coaster train while it's in motion. The fundamental idea of the restraint is to protect the rider and keep them in the proper riding position throughout the duration of the ride. Commonly found restraints include lap bars, over-the-shoulder restraints and seat belts.

Road Wheel - A wheel attached to the car or train that rides on the top of the roller coaster rail or track. Road wheels are usually made of steel and coated with nylon, hard plastic or rubber.

Rolling Stock - Another term used to describe the roller coaster train or car.

Running Rails - A term used to describe the track or rails the train or car on a roller coaster rides on.

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S

Seats - The location where the rider sits in the car or train while riding the roller coaster.

Seatbelt - A rather simple device used to help restrain and protect the rider. On some roller coasters like the Matterhorn at Disneyland this is the only restraint device, but on many other coasters seat belts are being used in addition to another restraint like a lap bar.

Set-Up - A situation where the train stops outside the station for whatever reason.

Shoulder Harness - A device used to secure a rider's shoulders by placing a bar over the shoulder area, but unlike an over-the-shoulder restraint it does not go down over the chest, stomach and cross the riders lap. Also see Over-The-Shoulder Restraint.

Shuttle - A term used to describe a roller coaster track that does not form a complete circuit. Instead the train or car is required to traverse the track in one direction and then reverse directions and return by repeating the course over again going in the opposite direction. The Boomerang at Knott's Berry Farm and Superman Ultimate Escape at Six Flags Worlds of Adventure are examples of shuttle coasters.

Side Friction - A roller coaster designed with guide rails above and on the outside of the track or running rails. The guide rails keep the train or car on the track without the use of guide wheels or upstops. Leap the Dips at Lakemont Park is an example of a side friction roller coaster.

Sidewinder - An inversion element on a roller coaster that makes a 90-degree turn while the train is inverted.

Single Loop - A roller coaster layout that only contains one, vertical loop.

Speed Bump - A small hill placed in a location where it will be taken at a high speed and will produce negative g-forces or airtime lifting the riders out of their seats.

Speed Run - A series of speed bumps in a row. Speed runs are commonly found on out and back wooden coasters and hypercoasters on the section of track after the turnaround that leads back to the station.

Spinning Wild Mouse - A Wild Mouse coaster designed with cars that spin during the entire course or parts of the roller coaster. The spinning is not controlled by mechanics, but instead by gravity, weight distribution and other forces caused by the ride.

Standing But Not Operating (SBNO) - This term describes a roller coaster that is closed, but remains standing and is not operational at this time. This term does not describe a roller coaster simply closed during a park's off season or downtime.

Stand-Up Roller Coaster - A roller coaster design that permits the riders to stand during the entire ride instead of being seated.

Station - The station is a building or structure that houses the loading and unloading platforms for a roller coaster. The station may also contain the ride's control panel, maintenance shed and a train storage area or transfer track.

Station Brake - A device used to slow or stop the train as it approaches and enters the station.

Steel Roller Coaster - A roller coaster built with steel rails. The track or rails determine if a roller coaster is considered a steel or wooden coaster, not the structure. Gemini at Cedar Point is an example of a steel roller coaster with a wooden support structure.

Steel Structure - The term used to describe a support structure on a roller coaster made of steel. Generally, this term is used for wooden roller coasters that feature an underlying structure made out of steel. Steel structures require less maintenance than wooden structures, thus saving the park money in the long run.

Straight - Used to describe a section of a coaster layout where the track runs straight, with no curves or turns. A straight is commonly found on launched roller coasters. Examples are Rock �n Roller Coaster at Disney MGM Studios or Superman The Escape at Six Flags Magic Mountain.

Suspended - A roller coaster designed where the trains ride below the track rather than on top of the track. The Arrow Suspended coasters including Big Bad Wolf at Busch Gardens Williamsburg and Ninja at Six Flags Magic Mountain feature special trains that are designed to swing freely from side to side. Also see Inverted Coaster and Suspended Looping Coaster.

Suspended Looping Coaster (SLC) - A term used by Vekoma to describe its inverted roller coaster design.

Swoop Term - A turn that incorporates a medium-to-small dip in the middle of the turn. A swoop turn usually begins at the crest of the hill and descends into the turn and then ascends out of the turn to crest another hill.

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T

Terrain Roller Coaster - A term used to describe a roller coaster layout that makes use of the terrain and natural surroundings. The coaster track is generally kept low to the ground and the surrounding terrain generally adds to the ride experience.

Theme Park - A term used to describe an amusement park that is designed to carry a theme in one or more areas of the park. The theme may carry over to the rides and attractions in that area as well. Examples of theme parks include Holiday World, Islands of Adventure, Disneyland, Magic Kingdom and Knott's Berry Farm.

Themed Roller Coaster - Describes a roller coaster that has a theme or story and uses effects such as lighting, sound, props or other elements to enhance the ride experience and carry on the theme or tell the story. Most themed roller coasters are enclosed but some like the Dueling Dragons at Islands of Adventure and Big Thunder Mountain Railroad at Magic Kingdom are not.

Thrust Air -

Tire Drive Lift Hill - A lift hill that uses tires to pinch the steel fin on the undercarriage of a car or train to drive the vehicle up the hill. Tire drive lifts may also use tires that just come in contact with a surface on the underside of the car or train to push or drive it up the lift hill.

Traditional Amusement Park - A term used to describe an amusement park that continues to operate in a manner similar to the way parks operated in the early 1900's. Examples include Kennywood, Knoebels Amusement Resort, Lake Compounce, and Playland Park in Rye, New York.

Train - A group of one or more cars linked together to form a roller coaster train.

Transfer Track - A section of track used to move a roller coaster car or train off the main circuit and onto a separate section of track. The transfer track usually connects to the car barn or a section of track typically used for storing a train or car when it is not in use. Also, see Car Barn.

Trim Brake - A brake used to slow a roller coaster train or car. Trim brakes are typically found in the middle of the circuit and are used to slow a train when it is exceeding the optimal operating speed. Trim brakes may be used to reduce the amount of negative g-forces on a ride. Block brakes which are designed to stop a train mid-course may also be used similar to trim brakes to trim speed off a roller coaster train.

Triple Out and Back - A roller coaster layout similar to an out and back, except that the course leaves and returns to near the station three times. Also see Out and Back and Double Out and Back.

Turnaround - A term that describes a turn on a roller coaster that sends the train back going in the opposite direction it came from. Turnarounds are common on roller coasters with an out and back layout.

Twister - Describes a roller coaster layout that features many turns, crossovers and track that runs in many directions. A twister is a roller coaster layout that is unpredictable. Examples include Roar at Six Flags Marine World, Cyclone at Astroland, and Wildcat at Hersheypark.

Two Lift Hills - A roller coaster that includes two lift hills.

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U

Unloading Platform - The part of the station where the passengers unload from the train or car. On many roller coasters the loading and unloading platform is the same thing.

Upstops - A part of a train that is generally a flat piece of steel with a nylon or rubber surface that is attached to the train and placed underneath the track or to keep the train from flying off. If the upstop comes in contact with the track due to the train rising from negative g-forces it will slide along the track and prevent the train from rising any further.

Upstop Wheels - A wheel attached to the train or car that rolls underneath the track to keep the train from coming off.

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V

Vertical Loop - A term used to describe an inversion that is a 360-degree loop placed in a vertical position where riders are sent upside down once.

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W

Weight Drop Launch - Found on some versions of the Schwarzkopf Shuttle Loop roller coasters. The weight drop launch uses a large weight attached by steel cables to pulleys that when released pulls the train from the station, accelerating it to its top speed. Also see: Catapult Launch, Compressed Air Launch, Flywheel Launch, LIM and LSM.

Wheels - Describes the part of the roller coaster car or train that rolls on the rails or track. Wheels are typically steel with a nylon or rubber coating on the outside to reduce the noise steel to steel contact would make and the heat generated by friction. There are three types of wheels on a roller coaster. Also see Guide Wheel, Road Wheel and Upstop Wheel.

Wild Mouse - A term that describes a type of roller coaster with sharp, turns that are not banked and quick steep drops. Wild Mouse coaster typically run with two or four passenger individual cars as opposed to trains.

Wingover - A term used to describe a half-corkscrew inversion element on Bolliger and Mabillard inverted roller coasters.

Wood Structure - Describes the support structure of a roller coaster that is made out of wood. Note that steel and wooden roller coasters are defined by the track material not the material used to build the underlying structure.

Wooden Roller Coaster - A roller coaster that uses layers of laminated wood with a flat steel rail attached to the top and inside as the track. Examples of wooden coasters are GhostRider at Knott's Berry Farm and Colossus at Six Flags Magic Mountain.

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