Wooden Coasters: braking systems.

The first wooden coasters had an employee riding a seat in the middle of the train. Those “scenic railways” were side friction rides and the brakeman would slow the train down in order to safely go down the hills and cross the dips. The brakeman would pull a lever and this would drop down sabots which would rub against the running wheels and slow the train down.

Later on, the brakeman was replaced by brakes mounted on track sections. The first brakes are traditionally referred to as “skid brakes”. The version most often seen involve mounting two parallel pieces of wood on a frame. The pieces of wood have a metal covering that is not smooth and rather coarse to help with friction. The train is slowed down by having the whole frame come up and rub against two friction plates under the car. The main advantage of that system is that the brakes frames can be build which ever way the designer needs it to be. In the case of many older rides, the final curve of the ride which leads into the station was the brake run.

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The two pieces of wood in the center of the track are the brakes. They lift and rub against friction pads.

The older brakes were activated by a few different systems depending on the manufacturer and ride configuration. A popular “speed adjuster” system was to have the frame mounted on a large lever. That lever had ratchet positions and the maintenance worker would manually adjust the position of the brakes with a pin. As well, to counter the action of the train that would try to lower the brake, the maintenance would add a large quantity of weight and adjust it depending on the season. The Phoenix at Knoebels (Elysburg, PA) has a large cement counterweight for the speed reduction brake. The height of the brake would vary based on weather and expectations of the train loads. Also, if the ride was to run two trains that day, the speed reducing brake before the safety brakes would need to trim more speed to provide a more comfortable stop in the pre station brakes.

The station and pre station brakes would often be operated by a cable and pulley system connected to a large lever in the station. When the brakes would be in the UP position, the lever would be tied to a rope to prevent it from moving when not in use. When operated, the rope would be removed and the operator could then lower the brakes as he saw fit to park the train in the unload or load position.

Later on, the station brake mechanical system was replaced by a pneumatic system. There would be small throttle joysticks that would allow the ride operator to control his brakes. Eventually, after the Matterhorn Bobsleds in 1959, many rides were converted to have automated braking. This reduced greatly the possibilities of overshoot in the station and made the ride a lot safer.

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Pneumatic actuator used on the Monstre at La Ronde (Montreal, QC). Note the backup springs. In this case, the brakes are in the “lower position” and thus allow the train to roll down. In the case of an air pressure leak, the springs would pull the brakes back into the “upper position” and stop the train.

Skid brakes are not very efficient when they are wet, so the braking areas need to be covered to prevent issues. Also, starting in the 1990’s, most parks in North America systematically go down to a one train operation when it start raining.

National Amusement Device came up with the first roller coaster fin brakes. Those rides which eventually became the industry standard consist of a steel fin bolted vertically under the train. On the track are two parallel “jaws” mounted in a caliper position which grip the fin and thus slow or stop the train. On the first installations, the brake calipers were mechanically operated like skid brakes. Then, NAD made them pneumatic using throttles. A great example of those brakes is at Camden Park in Huntingdon, WV. The Big Dipper (1958) use the mechanical fin brakes and the junior sized Lil’ Dipper (1961) use the pneumatic brakes.

In 1985, The Texas Cyclone at Astroworld (Houston, TX) got its braking system modified. It went from friction brakes to Arrow Dynamics pneumatic pinch brakes. The two PTC trains that ran at the time on the roller coaster had a braking fin retrofitted to one of the under carrier friction plate. In 1987, when the ride gained its infamous “Coffin Cars” from DH Morgan, the fins were designed and manufactured into the trains.

Up until around 1981-1982, with a few exceptions, the standard remained skid brakes on roller coasters. Around that time, Philadelphia Toboggan Co. (now the Philadelphia Toboggan Coasters Inc./PTC) adapted the fin brakes to their trains and started manufacturing brakes and retrofitting braking fins to their existing cars. The first ride to be confirmed to have opened with PTC fin brakes was the Grizzly at Kings Dominion (Doswell, VA) in 1982. The fin brakes allowed braking areas to be shorter and to not be covered like the skid brakes. Many parks will run only one train on their when there is a threat of rain and the fin brakes do not have that disadvantage. They are more reliable from an operational point of view.

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The PTC brakes use a long vertical fin mounted under the car. The fin on a PTC train is around 1 inch wide and is grabbed by calipers mounted in the middle of the track. Those long calipers are sometimes as long as the car and activate by an air servo. The brakes are closed by springs once air is no longer applied to give a fail-safe braking system. In the station and slower speed sections, PTC also manufactures shorter lengths of calipers. This is used for example by Gravity Group in the station of the Wooden Warrior roller coaster (Quassy, Middlebury, CT).

The PTC fin brakes are very efficient in stopping a train quickly and on a short distance. Custom Coasters International (CCI) frequently took advantage of that and featured very short braking areas at the end where only 4 or 5 calipers were placed. Tonnerre de Zeus at Parc Asterix (Plailly, France) opened in 1997 with only four brake jaws and featured a sudden and abrupt braking motion.

After that, many parks modified their rides to remove the skid brakes and install the new PTC fin brakes. But, there were some struggles with that. For example, the Great American Scream Machine at Six Flags Over Georgia (Austell, GA) used to have curved skid brakes. When the ride got equipped with new brakes, the fin brakes can only go on straight track sections. So, all the brakes had to be concentrated in a small straight area and it gave a more sudden and violent braking motion than before. With time, the park managed to adjust the brakes, but at first, it was a struggle. Another issue is that for some rides, such as the PTC built Yankee Cannonball at Canobie Lake Park (Salem, NH), the track does not allow enough clearance to allow a fin to safely be installed.

CCI retrofitted their own fin brakes on some older roller coasters, like the Montana Rusa at La Feria de Chapultapec (Ciudad de Mexico, MX) and the now closed Screechin’ Eagle at Americana/LeSourdville Lake (Middletown, OH).

In 2000, Intamin supplied the ride hardware and trains for the Magnus Colossus at Terra Mitica (Benidorm, Spain). Designed by Dennis Starkey and the Stand Company and built by the Roller Coaster Corporation of America, Intamin installed for the first time on a wooden coaster magnetic brakes. Those rare earth permanent magnets are mounted in a regular caliper configuration and work on the eddy-current principle. The main idea is that the braking power is proportional to the speed of the train. This provides a smooth braking motion, but they are unable to completely stop and hold the train. Intamin solution to that was to use large heavy duty drive tires to stop the trains in the pre course braking area and station area in a similar set up to their steel Mega Coaster and Giga Coaster installations.

2000 saw a new player enter the wooden coaster business: Vekoma. That year, as a part of a major project to transform Walibi Flevo (Flevoland, Netherlands) into Six Flags Holland, Vekoma sold 5 new attractions to Six Flags for that park, including a wooden coaster. Robin Hood at that park used standard Vekoma pneumatic pinch brakes to slow and stop the trains. It was so successful that was Six Flags ordered another wooden coaster in 2001 for the Walibi Wavre (Wavre, Belgium) transformation into Six Flags Belgium and Tusenfryd near Oslo, Norway also ordered a wooden coaster.

2002 saw Premier Rides third foray into the wooden coaster area and it was at Kings Island (Mason, OH). The Beast was involved in an incident the year before and the park decided to change the whole braking process. The 3 existing PTC trains were modified by Premier to receive brake fins and many parts of the ride rebuilt to remove the skid brakes and install new brake calipers. The innovation here was that Premier was the first to come up with the right metal alloy for the fins that would be react well enough to eddy current brakes and yet be durable enough for standard pneumatic mechanical braking. So, The Beast feature Premier fin brakes in the station, before the transfer section and 2 pre station braking zones. The rest of the ride as well as the speed reduction zone at the end feature strips of eddy current brakes that can easily be removed in the fall season when temperature falls and the ride need more speed to complete the course.

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This strip of magnetic brakes is installed in the pre station brake run of the Beast.

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Premier Rides also offer those adjustable/mobile brakes.

In 2003, Great Coasters International Inc. (GCII) came up with their own version of the fin brakes. In that case, the calipers are of a different shape and use smaller pads inside. Later on, in 2007, they also started using eddy-current magnetic brakes to trim most of the speed to reduce wear and tear on the brake fins and calipers.

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This picture show the main section of a GCII fin brake caliper.

In May 2004, there was a fire at the Pleasure Beach in Blackpool, UK and it destroyed the station of the Grand National, a 1935 classic wooden roller coaster. Pleasure Beach called in Kumbak, a Dutch engineering firm. They installed a brand new modern ride control system and installed a mixed fin based pneumatic calipers/eddy current braking system on the reformed Grand National. The fins on the new PTC trains were also changed by Kumbak to work with their equipment. The project was completed quickly and the ride reopened in October of the same year.

Kumbak was formed in 2001 after Vekoma underwent financial hardships that year. Some engineers branched off and formed an engineering firm that specializes in ride upgrades and refurbishment. In 2007, Port Aventura called in Kumbak to do an upgrade to the ride control system, braking system and change the trains on Stampida. Stampida is a 1997 Custom Coasters International (CCI) racing/dueling wooden roller coaster that was experiencing some heavy wear and tear issues on the trains. Kumbak came in in 2007, designed and built four new trains and installed at the same time new brakes. It is the same combination of the pneumatic calipers/eddy current brakes that were installed 3 years earlier on Grand National. Tomahawk, the sister junior ride to the Stampida also had the same control and braking upgrades.

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These pictures show the magnetic brakes on Stampida:

Photo: Kumbak

Kumbak worked on another project in 2010. Bakken (Klampenborg, Danemark) decided to upgrade its classic scenic railway, the Rutschebanen. It opened in 1932 and still had the original trains with the brakeman riding on board. Kumbak came in and combined a Rockwell Automation Allen-Bradley Guardlogix safety controller with pneumatic friction brakes and magnetic brakes. Three new trains were built and thanks to the new braking and control system, no brakeman is necessary and the ride now is TUV approved.

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The green plate in front of the train is one of the magnetic brake used on the ride.

Photo: Kumbak

Velocity Magnetics came onto the scene in the early 2000’s. They are today a large supplier of magnetic brakes to many manufacturers, such as Rocky Mountain Construction. RMC use Dyna-Brake magnetic brakes on their installations, such as Outlaw Run at Silver Dollar City (Branson, MO). The other brakes used on Outlaw Run are similar in shape and function to the Arrow pneumatic squeeze brakes.

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One major innovation for Velocity Magnetics is magnetic friction brakes, first introduced in 2012 on the Comet at Waldameer Park (Erie, PA). For this project, the park removed approximately 175 feet of track from the station and brake run. Velocity Magnetics then manufactured pre molded steel track that was bolted to the existing structure. The wooden running boards were bolted to the top of the running steel. Meanwhile, one car of the two PTC junior trains was sent to Velocity for modifications. The pads under the car were replaced by a new alloy that is both resistant and compatible with the rare earth magnets that will slow down the train in the 3 fixed magnetic brake sections. Then, 5 pneumatic friction brake sections will slow down the train and hold it. The load and unload has two more sections that are independently controlled.