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The Zipper is an amusement ride popular at carnivals and amusement parks in the United States, Canada, Australia and New Zealand. It features strong vertical G-forces, numerous spins, and a noted sense of unpredictability. The ride was invented by Joseph Brown under Chance Rides, a company based in Kansas that has manufactured more than 200 units since the ride's debut in 1968.
Most models of the Zipper follow a similar basic format: A long, rotating, oval boom with a cable around its edge that pulls 12 cars around the ride. Except at peak times, most operators will only fill half of the cars at one time with riders. Like most carnival equipment, the ride is designed to be portable. It can be disassembled onto a truck and transported from site to site.
The Zipper has a long oblong frame (the boom) that rotates like a Ferris wheel, with free-flipping cars suspended on off-center axes that move around the sides of the boom via a pulley system. Each passenger capsule is essentially a bench seat that snugly fits two people, built into a compartment of metal mesh contoured to protect the riders' entire bodies. The odd, apostrophe-shaped capsules, spaced evenly along the perimeter of the boom, look very much like the rows of interlocking teeth on a zipper, the characteristic for which the ride was named.
The passenger capsules travel around the perimeter of the boom at 4 revolutions per minute (rpm), not particularly fast, but the "flip" around the end of the oblong frame causes a sudden burst of speed and sends the compartments flipping end over end. The boom itself rotates at 7.5 rpm in the same direction as the pulley system. This combined but offset rotation provides each capsule with a unique and unpredictable experience. Zippers rotate both clockwise and counter-clockwise, and most are run with several rotations in each direction constituting "one ride".
If the riders shift enough body weight in one direction, they may be able to flip the car even when the boom and the attached cable are motionless. Each car allows limited space for riders. The restraint system for the riders are a lap bar and bars to hang on to. Not holding on to this bar when the ride suddenly jerks can cause a rider's head to hit the door in front of them. Riders also have the ability to attempt to shift their weight to try to flip their car as many times as possible during the ride, even with the little extra space available in the car.
Safety issues and revisions 
The first fourteen Zippers manufactured spun at much higher speeds than modern models. The boom rotated at 11 rpm and the cable system at 7 rpm. These first-generation rides kept the passenger compartments spinning on their axes constantly, creating unsafe g-forces and causing impact-related injuries such as whiplash, bruises and back injuries. The safety hazard was quickly discovered and the mechanical rpms were permanently lowered to current speeds.
On September 7, 1977, the Consumer Product Safety Commission issued a public warning, urging carnival-goers not to ride the Zipper after four deaths occurred due to compartment doors opening mid-ride. The safety restraints being attached to the door itself, riders are left unrestrained whenever the door is open. The four victims all died after falling from their compartments. The failure was traced to original spring-close latches on the doors wearing out and not being replaced. Compartments on currently operating Zippers are secured using the original latch, a redundant latch approved by the CPSC, and a large R-Key pin as a third backup.
Despite these new safety features, the same scenario was repeated in July 2006 in Hinckley, Minnesota when two teenage girls were ejected from their compartment as the door swung open. Their door was apparently not properly closed by the operator who admitted to local law enforcement that he had not inserted the safety pin (R-Key) before starting the ride. Both of the victims, Erica Matrious and Breanna Larsen, survived the incident despite facing some serious injuries. On November 2, 2006, the girls were interviewed.
Many newer models of Zipper have solved this problem by completely restructuring the door lock system, also eliminating the need for an R-key. These newer models have also increased the weight of the compartments, reducing the spinning, which decreases pressure on the door latches.
Zipper operators are encouraged to employ a "no single rider" policy. The manufacturer's concern was that a person riding alone might turn sideways in the seat and remove their legs from underneath the lap bar, risking serious injury as the capsule spun. The manufacturer sent out a bulletin to Zipper owners in 1995 pointing out the risk.
Ride duration 
- Ride duration (recommended): 2 minutes
- Ride duration (maximum): 2.5 minutes
- Maximum height: 56 feet (17.1 m)
- Total ride weight: 43,000 pounds (19,500 kg)
Passenger detail 
- Number of passenger compartments: Usually 12, some brands/models have 16
- Passengers per seat: 2 adults or 3 children
- Maximum passenger weight per seat: 500 pounds (227 kg)
- Total passengers: Maximum 24 adults or 36 children (12-seat Zipper)
- Maximum total passenger weight: 4,080 pounds (1,851 kg) (12-seat Zipper)
- Height requirement: 150 cm
Mechanical speed 
- Boom: 7.5 RPM (formerly 11 RPM, see above)
- Cable: 4.0 RPM (formerly 7 RPM, see above)
Direction of travel 
- Boom: travels clockwise or counter-clockwise
- Cable: travels clockwise or counter-clockwise
Power requirements 
- Boom drive: Electro-hydraulic
- Cable Drive: Electro-hydraulic
- Power rating: 25 horsepower (19 kW)
- Suspension type: Air ride
See also 
|Wikimedia Commons has media related to: Zipper (ride)|
- Ericson, Steve (2006-07-09). "Two hurt in carnival ride accident in Hinckley". Local News. Minneapolis, MN 55427, United States: KARE-11, a Division of Multimedia Holdings Corporation. Archived from the original on 2009-10-23. Retrieved 2009-10-23.
- "Service Bulletin, number B090R1169-A" (PDF). Des Moines, Iowa 50301-8236, United States: Chance Rides, Inc. 1995-04-21. Retrieved 2011-10-31.